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• Exam 70-480 Study Material: Programming in HTML5 with JavaScript and CSS3

  - by Stacy Vicknair

  Here’s a list of sources of information for the different elements that comprise the 70-480 exam: General Resources http://www.w3schools.com (As pointed out in David Pallmann’s blog some of this content is unverified, but it is a decent source of information. For more about when it isn’t decent, see http://www.w3fools.com ) http://www.bloggedbychris.com/2012/09/19/microsoft-exam-70-480-study-guide/ (A guy who did a lot of what I did already, sadly I found this halfway through finishing my resources list. This list is expertly put together so I would recommend checking it out.) http://davidpallmann.blogspot.com/2012/08/microsoft-certification-exam-70-480.html http://pluralsight.com/training/Courses (Yes, this isn’t free, but if you look at the course listing there is an entire section on HTML5, CSS3 and Javascript. You can always try the trial!)   Some of the links I put below will overlap with the other resources above, but I tried to find explanations that looked beneficial to me on links outside those already mentioned.   Test Breakdown Implement and Manipulate Document Structures and Objects (24%) Create the document structure. o This objective may include but is not limited to: structure the UI by using semantic markup, including for search engines and screen readers (Section, Article, Nav, Header, Footer, and Aside); create a layout container in HTML http://www.w3schools.com/html/html5_new_elements.asp   Write code that interacts with UI controls. o This objective may include but is not limited to: programmatically add and modify HTML elements; implement media controls; implement HTML5 canvas and SVG graphics http://www.w3schools.com/html/html5_canvas.asp http://www.w3schools.com/html/html5_svg.asp   Apply styling to HTML elements programmatically. o This objective may include but is not limited to: change the location of an element; apply a transform; show and hide elements   Implement HTML5 APIs. o This objective may include but is not limited to: implement storage APIs, AppCache API, and Geolocation API http://www.w3schools.com/html/html5_geolocation.asp http://www.w3schools.com/html/html5_webstorage.asp http://www.w3schools.com/html/html5_app_cache.asp   Establish the scope of objects and variables. o This objective may include but is not limited to: define the lifetime of variables; keep objects out of the global namespace; use the “this” keyword to reference an object that fired an event; scope variables locally and globally http://robertnyman.com/2008/10/09/explaining-javascript-scope-and-closures/ http://www.quirksmode.org/js/this.html   Create and implement objects and methods. o This objective may include but is not limited to: implement native objects; create custom objects and custom properties for native objects using prototypes and functions; inherit from an object; implement native methods and create custom methods http://www.javascriptkit.com/javatutors/object.shtml http://www.crockford.com/javascript/inheritance.html http://stackoverflow.com/questions/1635116/javascript-class-method-vs-class-prototype-method http://www.javascriptkit.com/javatutors/proto.shtml     Implement Program Flow (25%) Implement program flow. o This objective may include but is not limited to: iterate across collections and array items; manage program decisions by using switch statements, if/then, and operators; evaluate expressions http://www.javascriptkit.com/jsref/looping.shtml http://www.javascriptkit.com/javatutors/varshort.shtml http://www.javascriptkit.com/javatutors/switch.shtml   Raise and handle an event. o This objective may include but is not limited to: handle common events exposed by DOM (OnBlur, OnFocus, OnClick); declare and handle bubbled events; handle an event by using an anonymous function http://dev.w3.org/2006/webapi/DOM-Level-3-Events/html/DOM3-Events.html http://javascript.info/tutorial/bubbling-and-capturing   Implement exception handling. o This objective may include but is not limited to: set and respond to error codes; throw an exception; request for null checks; implement try-catch-finally blocks http://www.javascriptkit.com/javatutors/trycatch.shtml   Implement a callback. o This objective may include but is not limited to: receive messages from the HTML5 WebSocket API; use jQuery to make an AJAX call; wire up an event; implement a callback by using anonymous functions; handle the “this” pointer http://www.w3.org/TR/2011/WD-websockets-20110419/ http://www.html5rocks.com/en/tutorials/websockets/basics/ http://api.jquery.com/jQuery.ajax/   Create a web worker process. o This objective may include but is not limited to: start and stop a web worker; pass data to a web worker; configure timeouts and intervals on the web worker; register an event listener for the web worker; limitations of a web worker https://developer.mozilla.org/en-US/docs/DOM/Using_web_workers http://www.html5rocks.com/en/tutorials/workers/basics/   Access and Secure Data (26%) Validate user input by using HTML5 elements. o This objective may include but is not limited to: choose the appropriate controls based on requirements; implement HTML input types and content attributes (for example, required) to collect user input http://diveintohtml5.info/forms.html   Validate user input by using JavaScript. o This objective may include but is not limited to: evaluate a regular expression to validate the input format; validate that you are getting the right kind of data type by using built-in functions; prevent code injection http://www.regular-expressions.info/javascript.html http://msdn.microsoft.com/en-us/library/66ztdbe6(v=vs.94).aspx https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/typeof http://blog.stackoverflow.com/2008/06/safe-html-and-xss/ http://stackoverflow.com/questions/942011/how-to-prevent-javascript-injection-attacks-within-user-generated-html   Consume data. o This objective may include but is not limited to: consume JSON and XML data; retrieve data by using web services; load data or get data from other sources by using XMLHTTPRequest http://www.erichynds.com/jquery/working-with-xml-jquery-and-javascript/ http://www.webdevstuff.com/86/javascript-xmlhttprequest-object.html http://www.json.org/ http://stackoverflow.com/questions/4935632/how-to-parse-json-in-javascript   Serialize, deserialize, and transmit data. o This objective may include but is not limited to: binary data; text data (JSON, XML); implement the jQuery serialize method; Form.Submit; parse data; send data by using XMLHTTPRequest; sanitize input by using URI/form encoding http://api.jquery.com/serialize/ http://www.javascript-coder.com/javascript-form/javascript-form-submit.phtml http://stackoverflow.com/questions/327685/is-there-a-way-to-read-binary-data-into-javascript https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/encodeURI     Use CSS3 in Applications (25%) Style HTML text properties. o This objective may include but is not limited to: apply styles to text appearance (color, bold, italics); apply styles to text font (WOFF and @font-face, size); apply styles to text alignment, spacing, and indentation; apply styles to text hyphenation; apply styles for a text drop shadow http://www.w3schools.com/css/css_text.asp http://www.w3schools.com/css/css_font.asp http://nicewebtype.com/notes/2009/10/30/how-to-use-css-font-face/ http://webdesign.about.com/od/beginningcss/p/aacss5text.htm http://www.w3.org/TR/css3-text/ http://www.css3.info/preview/box-shadow/   Style HTML box properties. o This objective may include but is not limited to: apply styles to alter appearance attributes (size, border and rounding border corners, outline, padding, margin); apply styles to alter graphic effects (transparency, opacity, background image, gradients, shadow, clipping); apply styles to establish and change an element’s position (static, relative, absolute, fixed) http://net.tutsplus.com/tutorials/html-css-techniques/10-css3-properties-you-need-to-be-familiar-with/ http://www.w3schools.com/css/css_image_transparency.asp http://www.w3schools.com/cssref/pr_background-image.asp http://ie.microsoft.com/testdrive/graphics/cssgradientbackgroundmaker/default.html http://www.w3.org/TR/CSS21/visufx.html http://www.barelyfitz.com/screencast/html-training/css/positioning/ http://davidwalsh.name/css-fixed-position   Create a flexible content layout. o This objective may include but is not limited to: implement a layout using a flexible box model; implement a layout using multi-column; implement a layout using position floating and exclusions; implement a layout using grid alignment; implement a layout using regions, grouping, and nesting http://www.html5rocks.com/en/tutorials/flexbox/quick/ http://www.css3.info/preview/multi-column-layout/ http://msdn.microsoft.com/en-us/library/ie/hh673558(v=vs.85).aspx http://dev.w3.org/csswg/css3-grid-layout/ http://dev.w3.org/csswg/css3-regions/   Create an animated and adaptive UI. o This objective may include but is not limited to: animate objects by applying CSS transitions; apply 3-D and 2-D transformations; adjust UI based on media queries (device adaptations for output formats, displays, and representations); hide or disable controls http://www.bloggedbychris.com/2012/09/19/microsoft-exam-70-480-study-guide/   Find elements by using CSS selectors and jQuery. o This objective may include but is not limited to: choose the correct selector to reference an element; define element, style, and attribute selectors; find elements by using pseudo-elements and pseudo-classes (for example, :before, :first-line, :first-letter, :target, :lang, :checked, :first-child) http://www.bloggedbychris.com/2012/09/19/microsoft-exam-70-480-study-guide/   Structure a CSS file by using CSS selectors. o This objective may include but is not limited to: reference elements correctly; implement inheritance; override inheritance by using !important; style an element based on pseudo-elements and pseudo-classes (for example, :before, :first-line, :first-letter, :target, :lang, :checked, :first-child) http://www.bloggedbychris.com/2012/09/19/microsoft-exam-70-480-study-guide/   Technorati Tags: 70-480,CSS3,HTML5,HTML,CSS,JavaScript,Certification

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• Issuing Current Time Increments in StreamInsight (A Practical Example)

  The issuing of a Current Time Increment, Cti, in StreamInsight is very definitely one of the most important concepts to learn if you want your Streams to be responsive. A full discussion of how to issue Ctis is beyond the scope of this article but a very good explanation in addition to Books Online can be found in these three articles by a member of the StreamInsight team at Microsoft, Ciprian Gerea. Time in StreamInsight Series http://blogs.msdn.com/b/streaminsight/archive/2010/07/23/time-in-streaminsight-i.aspx http://blogs.msdn.com/b/streaminsight/archive/2010/07/30/time-in-streaminsight-ii.aspx http://blogs.msdn.com/b/streaminsight/archive/2010/08/03/time-in-streaminsight-iii.aspx A lot of the problems I see with unresponsive or stuck streams on the MSDN Forums are to do with how Ctis are enqueued or in a lot of cases not enqueued. If you enqueue events and never enqueue a Cti then StreamInsight will be perfectly happy. You, on the other hand, will never see data on the output as you have not told StreamInsight to flush the stream. This article deals with a specific implementation problem I had recently whilst working on a StreamInsight project. I look at some possible options and discuss why they would not work before showing the way I solved the problem. The stream of data I was dealing with on this project was very bursty that is to say when events were flowing they came through very quickly and in large numbers (1000 events/sec), but when the stream calmed down it could be a few seconds between each event. When enqueuing events into the StreamInsight engne it is best practice to do so with a StartTime that is given to you by the system producing the event . StreamInsight processes events and it doesn't matter whether those events are being pushed into the engine by a source system or the events are being read from something like a flat file in a directory somewhere. You can apply the same logic and temporal algebra to both situations. Reading from a file is an excellent example of where the time of the event on the source itself is very important. We could be reading that file a long time after it was written. Being able to read the StartTime from the events allows us to define windows that will hold the correct sets of events. I was able to do this with my stream but this is where my problems started. Below is a very simple script to create a SQL Server table and populate it with sample data that will show exactly the problem I had. CREATE TABLE [dbo].[t] ( [c1] [int] PRIMARY KEY, [c2] [datetime] NULL ) INSERT t VALUES (1,'20100810'),(2,'20100810'),(3,'20100810') Column c2 defines the StartTime of the event on the source and as you can see the values in all 3 rows of data is the same. If we read Ciprian’s articles we know that we can define how Ctis get injected into the stream in 3 different places The Stream Definition The Input Factory The Input Adapter I personally have always been a fan of enqueing Ctis through the factory. Below is code typical of what I would use to do this On the class itself I do some inheriting public class SimpleInputFactory : ITypedInputAdapterFactory<SimpleInputConfig>, ITypedDeclareAdvanceTimeProperties<SimpleInputConfig> And then I implement the following function public AdapterAdvanceTimeSettings DeclareAdvanceTimeProperties<TPayload>(SimpleInputConfig configInfo, EventShape eventShape) { return new AdapterAdvanceTimeSettings( new AdvanceTimeGenerationSettings(configInfo.CtiFrequency, TimeSpan.FromTicks(-1)), AdvanceTimePolicy.Adjust); } The configInfo .CtiFrequency property is a value I pass through to define after how many events I want a Cti to be injected and this in turn will flush through the stream of data. I usually pass a value of 1 for this setting. The second parameter determines the CTI timestamp in terms of a delay relative to the events. -1 ticks in the past results in 1 tick in the future, i.e., ahead of the event. The problem with this method though is that if consecutive events have the same StartTime then only one of those events will be enqueued. In this example I use the following to define how I assign the StartTime of my events currEvent.StartTime = (DateTimeOffset)dt.c2; If I go ahead and run my StreamInsight process with this configuration i can see on the output adapter that two events have been removed To see this in a little more depth I can use the StreamInsight Debugger and see what happens internally. What is happening here is that the first event arrives and a Cti is injected with a time of 1 tick after the StartTime of that event (Also the EndTime of the event). The second event arrives and it has a StartTime of before the Cti and even though we specified AdvanceTimePolicy.Adjust on the factory we know that a point event can never be adjusted like this and the event is dropped. The same happens for the third event as well (The second and third events get trumped by the Cti). For a more detailed discussion of why this happens look here http://www.sqlis.com/sqlis/post/AdvanceTimePolicy-and-Point-Event-Streams-In-StreamInsight.aspx We end up with a single event being pushed into the output adapter and our result now makes sense. The next way I tried to solve this problem by changing the value of the second parameter to TimeSpan.Zero Here is how my factory code now looks public AdapterAdvanceTimeSettings DeclareAdvanceTimeProperties<TPayload>(SimpleInputConfig configInfo, EventShape eventShape) { return new AdapterAdvanceTimeSettings( new AdvanceTimeGenerationSettings(configInfo.CtiFrequency, TimeSpan.Zero), AdvanceTimePolicy.Adjust); } What I am doing here is declaring a policy that says inject a Cti together with every event and stamp it with a StartTime that is equal to the start time of the event itself (TimeSpan.Zero). This method has plus points as well as a downside. The upside is that no events will be lost by having the same StartTime as previous events. The Downside is that because the Cti is declared with the StartTime of the event itself then it does not actually flush that particular event because in the StreamInsight algebra, a Cti commits only those events that occurred strictly before them. To flush the events we need a Cti to be enqueued with a greater StartTime than the events themselves. Here is what happened when I ran this configuration As you can see all we got through was the Cti and none of the events. The debugger output shows the stamps on the Cti and the events themselves. Because the Cti issued has the same timestamp (StartTime) as the events then none of the events get flushed. I was nearly there but not quite. Because my stream was bursty it was possible that the next event would not come along for a few seconds and this was far too long for an event to be enqueued and not be flushed to the output adapter. I needed another solution. Two possible solutions crossed my mind although only one of them made sense when I explored it some more. Where multiple events have the same StartTime I could add 1 tick to the first event, two to the second, three to third etc thereby giving them unique StartTime values. Add a timer to manually inject Ctis The problem with the first implementation is that I would be giving the events a new StartTime. This would cause me the following problems If I want to define windows over the stream then some events may not be captured in the right windows and therefore any calculations on those windows I did would be wrong What would happen if we had 10,000 events with the same StartTime? I would enqueue them with StartTime + n ticks. Along comes a genuine event with a StartTime of the very first event + 1 tick. It is now too far in the past as far as my stream is concerned and it would be dropped. Not what I would want to do at all. I decided then to look at the Timer based solution I created a timer on my input adapter that elapsed every 200ms. private Timer tmr; public SimpleInputAdapter(SimpleInputConfig configInfo) { ctx = new SimpleTimeExtractDataContext(configInfo.ConnectionString); this.configInfo = configInfo; tmr = new Timer(200); tmr.Elapsed += new ElapsedEventHandler(t_Elapsed); tmr.Enabled = true; } void t_Elapsed(object sender, ElapsedEventArgs e) { ts = DateTime.Now - dtCtiIssued; if (ts.TotalMilliseconds >= 200 && TimerIssuedCti == false) { EnqueueCtiEvent(System.DateTime.Now.AddTicks(-100)); TimerIssuedCti = true; } }   In the t_Elapsed event handler I find out the difference in time between now and when the last event was processed (dtCtiIssued). I then check to see if that is greater than or equal to 200ms and if the last issuing of a Cti was done by the timer or by a genuine event (TimerIssuedCti). If I didn’t do this check then I would enqueue a Cti every time the timer elapsed which is not something I wanted. If the difference between the two times is greater than or equal to 500ms and the last event enqueued was by a real event then I issue a Cti through the timer to flush the event Queue, otherwise I do nothing. When I enqueue the Ctis into my stream in my ProduceEvents method I also set the values of dtCtiIssued and TimerIssuedCti   currEvent = CreateInsertEvent(); currEvent.StartTime = (DateTimeOffset)dt.c2; TimerIssuedCti = false; dtCtiIssued = currEvent.StartTime; If I go ahead and run this configuration I see the following in my output. As we can see the first Cti gets enqueued as before but then another is enqueued by the timer and because this has a later timestamp it flushes the enqueued events through the engine. Conclusion Hopefully this has shown how the enqueuing of Ctis can have a dramatic effect on the responsiveness of your output in StreamInsight. Understanding the temporal nature of the product is for me one of the most important things you can learn. I have attached my solution for the demos. It is all in one project and testing each variation is a simple matter of commenting and un-commenting the parts in the code we have been dealing with here.

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• Stop Believing TV’s Lies: The Real Truth About "Enhancing" Images

  - by Eric Z Goodnight

  You’ve seen it over and over. The FBI uses their advanced technology to “enhance” a blurry image, and find a villain’s face in the worst possible footage. Well, How-To Geek is calling their bluff. Read on to see why. It’s one of the most common tropes in television and movies, but is there any possibility a government agency could really have the technology to find faces where there are only blurry pixels? We’ll make the argument that not only is it impossible with current technology, but it is very unlikely to ever be a technology we’ll ever see. Stick around to see us put this trope under the lenses of science and technology, and prove it wrong once and for all Latest Features How-To Geek ETC Stop Believing TV’s Lies: The Real Truth About "Enhancing" Images The How-To Geek Valentine’s Day Gift Guide Inspire Geek Love with These Hilarious Geek Valentines RGB? CMYK? Alpha? What Are Image Channels and What Do They Mean? How to Recover that Photo, Picture or File You Deleted Accidentally How To Colorize Black and White Vintage Photographs in Photoshop A History of Vintage Transformers: Decepticons Edition [Infographic] How to Determine What Kind of Comment to Leave on Facebook [Humorous Flow Chart] View the Cars of Tomorrow Through the Eyes of the Past [Historical Video] Add Romance to Your Desktop with These Two Valentine’s Day Themes for Windows 7 Gmail’s Priority Inbox Now Available for Mobile Web Browsers Touchpad Blocker Locks Down Your Touchpad While Typing

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• Creating a Dynamic DataRow for easier DataRow Syntax

  - by Rick Strahl

  I've been thrown back into an older project that uses DataSets and DataRows as their entity storage model. I have several applications internally that I still maintain that run just fine (and I sometimes wonder if this wasn't easier than all this ORM crap we deal with with 'newer' improved technology today - but I disgress) but use this older code. For the most part DataSets/DataTables/DataRows are abstracted away in a pseudo entity model, but in some situations like queries DataTables and DataRows are still surfaced to the business layer. Here's an example. Here's a business object method that runs dynamic query and the code ends up looping over the result set using the ugly DataRow Array syntax:public int UpdateAllSafeTitles() { int result = this.Execute("select pk, title, safetitle from " + Tablename + " where EntryType=1", "TPks"); if (result < 0) return result; result = 0; foreach (DataRow row in this.DataSet.Tables["TPks"].Rows) { string title = row["title"] as string; string safeTitle = row["safeTitle"] as string; int pk = (int)row["pk"]; string newSafeTitle = this.GetSafeTitle(title); if (newSafeTitle != safeTitle) { this.ExecuteNonQuery("update " + this.Tablename + " set safeTitle=@safeTitle where pk=@pk", this.CreateParameter("@safeTitle",newSafeTitle), this.CreateParameter("@pk",pk) ); result++; } } return result; } The problem with looping over DataRow objecs is two fold: The array syntax is tedious to type and not real clear to look at, and explicit casting is required in order to do anything useful with the values. I've highlighted the place where this matters. Using the DynamicDataRow class I'll show in a minute this code can be changed to look like this:public int UpdateAllSafeTitles() { int result = this.Execute("select pk, title, safetitle from " + Tablename + " where EntryType=1", "TPks"); if (result < 0) return result; result = 0; foreach (DataRow row in this.DataSet.Tables["TPks"].Rows) { dynamic entry = new DynamicDataRow(row); string newSafeTitle = this.GetSafeTitle(entry.title); if (newSafeTitle != entry.safeTitle) { this.ExecuteNonQuery("update " + this.Tablename + " set safeTitle=@safeTitle where pk=@pk", this.CreateParameter("@safeTitle",newSafeTitle), this.CreateParameter("@pk",entry.pk) ); result++; } } return result; } The code looks much a bit more natural and describes what's happening a little nicer as well. Well, using the new dynamic features in .NET it's actually quite easy to implement the DynamicDataRow class. Creating your own custom Dynamic Objects .NET 4.0 introduced the Dynamic Language Runtime (DLR) and opened up a whole bunch of new capabilities for .NET applications. The dynamic type is an easy way to avoid Reflection and directly access members of 'dynamic' or 'late bound' objects at runtime. There's a lot of very subtle but extremely useful stuff that dynamic does (especially for COM Interop scenearios) but in its simplest form it often allows you to do away with manual Reflection at runtime. In addition you can create DynamicObject implementations that can perform  custom interception of member accesses and so allow you to provide more natural access to more complex or awkward data structures like the DataRow that I use as an example here. Bascially you can subclass DynamicObject and then implement a few methods (TryGetMember, TrySetMember, TryInvokeMember) to provide the ability to return dynamic results from just about any data structure using simple property/method access. In the code above, I created a custom DynamicDataRow class which inherits from DynamicObject and implements only TryGetMember and TrySetMember. Here's what simple class looks like:/// <summary> /// This class provides an easy way to turn a DataRow /// into a Dynamic object that supports direct property /// access to the DataRow fields. /// /// The class also automatically fixes up DbNull values /// (null into .NET and DbNUll to DataRow) /// </summary> public class DynamicDataRow : DynamicObject { /// <summary> /// Instance of object passed in /// </summary> DataRow DataRow; /// <summary> /// Pass in a DataRow to work off /// </summary> /// <param name="instance"></param> public DynamicDataRow(DataRow dataRow) { DataRow = dataRow; } /// <summary> /// Returns a value from a DataRow items array. /// If the field doesn't exist null is returned. /// DbNull values are turned into .NET nulls. /// /// </summary> /// <param name="binder"></param> /// <param name="result"></param> /// <returns></returns> public override bool TryGetMember(GetMemberBinder binder, out object result) { result = null; try { result = DataRow[binder.Name]; if (result == DBNull.Value) result = null; return true; } catch { } result = null; return false; } /// <summary> /// Property setter implementation tries to retrieve value from instance /// first then into this object /// </summary> /// <param name="binder"></param> /// <param name="value"></param> /// <returns></returns> public override bool TrySetMember(SetMemberBinder binder, object value) { try { if (value == null) value = DBNull.Value; DataRow[binder.Name] = value; return true; } catch {} return false; } } To demonstrate the basic features here's a short test: [TestMethod] [ExpectedException(typeof(RuntimeBinderException))] public void BasicDataRowTests() { DataTable table = new DataTable("table"); table.Columns.Add( new DataColumn() { ColumnName = "Name", DataType=typeof(string) }); table.Columns.Add( new DataColumn() { ColumnName = "Entered", DataType=typeof(DateTime) }); table.Columns.Add(new DataColumn() { ColumnName = "NullValue", DataType = typeof(string) }); DataRow row = table.NewRow(); DateTime now = DateTime.Now; row["Name"] = "Rick"; row["Entered"] = now; row["NullValue"] = null; // converted in DbNull dynamic drow = new DynamicDataRow(row); string name = drow.Name; DateTime entered = drow.Entered; string nulled = drow.NullValue; Assert.AreEqual(name, "Rick"); Assert.AreEqual(entered,now); Assert.IsNull(nulled); // this should throw a RuntimeBinderException Assert.AreEqual(entered,drow.enteredd); } The DynamicDataRow requires a custom constructor that accepts a single parameter that sets the DataRow. Once that's done you can access property values that match the field names. Note that types are automatically converted - no type casting is needed in the code you write. The class also automatically converts DbNulls to regular nulls and vice versa which is something that makes it much easier to deal with data returned from a database. What's cool here isn't so much the functionality - even if I'd prefer to leave DataRow behind ASAP -  but the fact that we can create a dynamic type that uses a DataRow as it's 'DataSource' to serve member values. It's pretty useful feature if you think about it, especially given how little code it takes to implement. By implementing these two simple methods we get to provide two features I was complaining about at the beginning that are missing from the DataRow: Direct Property Syntax Automatic Type Casting so no explicit casts are required Caveats As cool and easy as this functionality is, it's important to understand that it doesn't come for free. The dynamic features in .NET are - well - dynamic. Which means they are essentially evaluated at runtime (late bound). Rather than static typing where everything is compiled and linked by the compiler/linker, member invokations are looked up at runtime and essentially call into your custom code. There's some overhead in this. Direct invocations - the original code I showed - is going to be faster than the equivalent dynamic code. However, in the above code the difference of running the dynamic code and the original data access code was very minor. The loop running over 1500 result records took on average 13ms with the original code and 14ms with the dynamic code. Not exactly a serious performance bottleneck. One thing to remember is that Microsoft optimized the DLR code significantly so that repeated calls to the same operations are routed very efficiently which actually makes for very fast evaluation. The bottom line for performance with dynamic code is: Make sure you test and profile your code if you think that there might be a performance issue. However, in my experience with dynamic types so far performance is pretty good for repeated operations (ie. in loops). While usually a little slower the perf hit is a lot less typically than equivalent Reflection work. Although the code in the second example looks like standard object syntax, dynamic is not static code. It's evaluated at runtime and so there's no type recognition until runtime. This means no Intellisense at development time, and any invalid references that call into 'properties' (ie. fields in the DataRow) that don't exist still cause runtime errors. So in the case of the data row you still get a runtime error if you mistype a column name:// this should throw a RuntimeBinderException Assert.AreEqual(entered,drow.enteredd); Dynamic - Lots of uses The arrival of Dynamic types in .NET has been met with mixed emotions. Die hard .NET developers decry dynamic types as an abomination to the language. After all what dynamic accomplishes goes against all that a static language is supposed to provide. On the other hand there are clearly scenarios when dynamic can make life much easier (COM Interop being one place). Think of the possibilities. What other data structures would you like to expose to a simple property interface rather than some sort of collection or dictionary? And beyond what I showed here you can also implement 'Method missing' behavior on objects with InvokeMember which essentially allows you to create dynamic methods. It's all very flexible and maybe just as important: It's easy to do. There's a lot of power hidden in this seemingly simple interface. Your move…© Rick Strahl, West Wind Technologies, 2005-2011Posted in CSharp  .NET   Tweet (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Geeks with Blogs acquired by Watson Technology Group

  - by Tarun Arora

  Just received the following email… It’s now official! Hello bloggers, you are receiving this email to let you know that Geeks with Blogs (http://geekswithblogs.net) has been acquired by my company, Watson Technology Group. Jeff Julian started the site in 2003 and since then him and John Alexander (AJI Software) have done a great job with the community. I am a long time friend of theirs and I was actually one of the first bloggers on the site in 2003. I am excited to take over the reins and I have a lot of plans to improve the blog platform and community. My goal is to make the site the #1 blogging site for all IT professionals. The site currently has over 3,000 bloggers and has received 75,000,000 website visitors over the last 5 years. Some of the planned improvements in the coming months: Overall look and feel upgrades to the site Improve editor for blog postings including support for code formatting and uploading images Mobile support and more responsive design templates Improve community side of the site to drive more traffic between blogs Highlight top articles and bloggers by redesigning the home page ... and lots of other things. One of the delicate balances I want to ensure is that each blogger can maintain their own identity and blog personality but at the same time be part of the community of bloggers. The community helps everyone receive more blog traffic and visibility. The blog templates need to be somewhere between Facebook and Myspace if you know what I mean. Since this website is designed to be a community, I would love to have your feedback and hear your ideas. Please submit idea via UserVoice at http://geekswithblogs.uservoice.com or email [email protected] at anytime. For those who are interested to know more about me, here is a link to my LinkedIn profile and you can follow me on Twitter @mattwatson81. LinkedIn: http://www.linkedin.com/in/mattwatsonkc Thanks, Matt Watson Geeks with Blogs Member of Geeks with Blogs Unsubscribe [email protected] from this list. Our mailing address is: GeeksWithBlogs,LLC 9201 Ward Parkway Suite 302 Kansas City, MO 64114

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• IE9 RC fixed the “Internet Explorer cannot display the webpage” error when running an ASP.NET application in Visual Studio

  - by Jon Galloway

  One of the obstacles ASP.NET developers faced in using the Internet Explorer 9 Beta was the dreaded “Internet Explorer cannot display the webpage” error when running an ASP.NET application in Visual Studio. In the bug information on Connect (issue 601047), Eric Lawrence said that the problem was due to “caused by failure to failover from IPv6 to IPv4 when the connection is local.” Robert MacLean gives some more information as what was going wrong: “The problem is Windows, especially since it assumes IPv6 is better than IPv4. Note […] that when you ping localhost you get an IPv6 address. So what appears to be happening is when IE9 tries to go to localhost it uses IPv6, and the ASP.NET Development Server is IPv4 only and so nothing loads and we get the error.” The Simple Fix - Install IE 9 RC Internet Explorer 9 RC fixes this bug, so if you had tried IE 9 Beta and stopped using it due to problems with ASP.NET development, install the RC. The Workaround in IE 9 Beta If you're stuck on IE 9 Beta for some reason, you can follow Robert's workaround, which involves a one character edit to your hosts file. I've been using it for months, and it works great. Open notepad (running as administrator) and edit the hosts file (found in %systemroot%\system32\drivers\etc) Remove the # comment character before the line starting with 127.0.0.1 Save the file - if you have problems saving, it's probably because you weren't running as administrator When you're done, your hosts file will end with the following lines (assuming you were using a default hosts file setup beforehand): # localhost name resolution is handled within DNS itself.     127.0.0.1       localhost #    ::1             localhost Note: more information on editing your hosts file here. This causes Windows to default to IPv4 when resolving localhost, which will point to 127.0.0.1, which is right where Cassini - I mean the ASP.NET Web Development Server - is waiting for it.

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• NINE Questions with Michelle Juett

  - by NINEQuestions

  Michelle Juett is one of the more interesting people I know, even though we’ve never met face to face. She’s part artist, part techie and all cool. We “met” via my good buddy George Clingerman and have plotting to take over the world, errr… I mean “collaborating” ever since. If you happen to live in the Seattle area, you can catch her and her work at Sakura Con on April 2-4, 2010 and various other gamer and art cons throughout the year. You can also find her on Twitter as @Shelldragon. Now that you know a little bit, I’ll let her tell you the rest of the story in these NINE Questions: 1. Where are you from? I was born in Clearwater, Florida. I like to tell people I'm from the Bermuda Triangle, it just makes explaining myself so much easier. My family moved to Washington when I was 5 and I've been in the Pacific Northwest ever since. We like to QQ about the rain but we really love the green trees and clean water. 2. What do you do? I fight evil by moonlight and win love by daylight.. or something like that.  I’ve been in quality assurance for games during the day since January 2008 and an artist for life. I currently work in QA for a really awesome game company in Bellevue.  At home, I work on personal digital art, making game assets as well as other random freelance projects as they pop up. 3. How did you get to where you are now? I'm still not where I want to be but I'm getting closer. The biggest piece of advice I can give is to work hard and never settle for the minimum required. I tend to overwork myself but I've never regretted it. You can want something really bad but if you aren't willing to work for it, then you can't expect it to just happen. I've always drawn and had an unhealthy love for video games that I was told I’d grow out of.  I knew I would not ‘grow out’ of games and that real adults make them and I could too. After I graduated, in searching for jobs, I discovered game testing. I figured this would be a good way to get my foot in the door and start networking. I’ve worked with consoles, websites and now, PC games.  I stuck with my journey, although it has been a rocky one, daylighting as a tester and moonlighting as an artist. I'm still on that journey but I wouldn't have it any other way. Test has given me a perspective that is difficult, if not impossible, to obtain any other way. It gives an unconditional respect for other hard working testers and an insight into creative problem solving. 4. So video game testing probably sounds WAY cooler than the reality. What's it like? What's a given day for you? Game testers don't get a lot of respect because of their stigmas and the fact most people don't actually know what we do.  People hear about the opening and closing disc trays all day. Many places do treat their testers like numbers. It all depends on where you work and how awesome your company is. I've had to deal with a lot of bad work situations to get to a really good one. QA exists to ensure the game is as flawless and enjoyable as it can be by the time it has to leave the nest and go out into the world. This includes everything obvious: “can I beat the level and save the princess?” to the more obscure: ‘What happens when I lose internet connection while trying to save right before falling into a pit to my death while holding the jump key then my cat pulls out my memory card and hides it in her litter box?” On the dev side, for developers, testers can be very scary people. Especially when the test team is not in house and you can’t see each other’s faces.  I've seen both sides. We don't mean to hurt your feelings. We really DO love you and want your game to be the best it can be! It can be some serious tough love. 5. You are also an accomplished artist. Got any major projects right now you'd like to talk about? LOL, I don't know if I’d say I'm an accomplished artist just yet. I’m still a long way from where I want to be. I figure that’s what makes you grow though: the desire to never stop improving. I like QA but I want to be a full time artist. I was lucky enough to register for a table at Sakura Con in the 11 second window that the tables sold out. As such, I’ll be selling my wares in the Artist Alley April 2-4th. Part of preparing for this is actually making the art to be sold there. Anime is a fun pass time but I don’t draw a whole lot of it so I’m making up for lost time. As I seem to enjoy burying myself in work, I’m an art lead for a secret project that’s so secret I might be killed tonight for even mentioning it. I also take on various freelance projects and do what I can to help out indie games. I discovered the XNA community a year and a half ago and developed a love for Indies when I was writing a weekly newsletter on XBLA news. I’m a little late to the party but I find myself in a unique position where I am an artist and also have technical skills in games. While not programmer myself, I have a lot of game sense and experience. I hope to make some awesome happen. Lastly, I have an ongoing web comic Shell’s Angels) that tends to get neglected when I get busy. I still love drawing comics and keep a little book with me to sketch down ideas as they pop into my head. I may pick it back up again as a larger project sometime in the future. 6. Can you talk about any of the other freelance projects you're doing or are you sworn to secrecy on those too? We wouldn't want a team of game developer ninjas to take you out or anything. All my projects are currently 2d. I have personal projects such as the ongoing comic as well as a graphic novel I've been picking at here and there. My main focus until April is Sakura Con, Sakura Con, Sakura Con.  I see it as a great way to get exposure and convention experience. I found out I love conventions a couple years ago and I want to get more involved in them. 7. As an artist, what is your weapon of choice? What do you use to get most of your stuff done? I am a Photoshop Hero and I have the hoodie to prove it. (http://www.pennyarcademerch.com/pah090011.html) I've dabbled in other paint programs but I always gravitate back to Photoshop. She is my one true love. I'd like to learn programs like Flash or Anime Studio when I get a bit more time because of their animation abilities. I've worked on frame by frame animation forever but I would love to learn 2d rigging. Still, nothing can compare to a simple sketchpad and a pencil. I always have one on me in case I come across or think of something interesting and can't get to a computer. If the Courier ever comes to exist it will be an ideal weapon for me. 8. You did some videos too, depicting the art creation process. What was the motivation behind those? The creative process is just as important as the final product, if not more so.  I've always loved watching speed paint videos and wanted to try it out myself. Turns out it's a lot of work and time but it's definitely fun to go back and rewatch them. Art isn't always the end result and is more often the process itself. 9. Got any interesting tattoos? Designed any for yourself or other people? Not yet, but not for lack of desire. I've toiled over what and where for years. Last year, I finally decided the back of my shoulders would be the place. Like anything permanent, I want it to have meaning. I thought of somehow incorporating games but I couldn't find something I felt would stand the test of time even with all the classic sprite games. I'm very picky so we'll see if I can get something solid decided. Come see me at Sakura Con April 2 -4!!!

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• Does a site's bounce rate influence Google rankings?

  - by Joel Spolsky

  Does Google consider bounce rate or something similar in ranking sites? Background: here at Stack Exchange we noticed that the latest Google algorithm changes resulted in about a 20% dip in traffic to Server Fault (and a much smaller dip in traffic to Super User). Stack Overflow traffic was not affected. There was an article on WebProNews which hypothesized that bounce rate might be a ranking signal in Google's latest Panda update. According to Google Analytics, these are our bounce rates over the last month: Site Bounce Rate Avg Time on Site ------------- ----------- ---------------- SuperUser 84.67% 01:16 ServerFault 83.76% 00:53 Stack Overflow 63.63% 04:12 Now, technically, Google has no way to know the bounce rate. If you go to Google, search for something, and click on the first result, Google can't tell the difference between: a user who turns off their computer a user who goes to a completely different web site a user who spends hours clicking around on the website they landed on What Google does know is how long it takes the user to come back to Google and do another search. According to the book In The Plex (page 47), Google distinguishes between what they call "short clicks" and "long clicks": A short click is a search where the user quickly comes back to Google and does another search. Google interprets this as a signal that the first search results were unsatisfactory. A long click is a search where the user doesn't search again for a long time. The book says that Google uses this information internally, to judge the quality of their own algorithms. It also said that short click data in which someone retypes a slight variation of the search is used to fuel the "Did you mean...?" spell checking algorithm. So, my hypothesis is that Google has recently decided to use long click rates as a signal of a high quality site. Does anyone have any evidence of this? Have you seen any high-bounce-rate sites which lost traffic (or vice-versa)?

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• Oracle CRM in the UK- Gartner CRM Summit 2010

  - by divya.malik

  We are now headed to the UK to co-sponsor and participate in the Gartner Customer Relationship Management Summit 2010 on the 16th and 17th of March in London. Oracle CRM Vice President Mark Woollen will be presenting on Tuesday, 16 March 2010 from 15:20-15:50 on                                                                                                                                          CRM is dead, long live CRM?  Everyone is saying the world has changed and with it a new set of acronyms/buzzwords/vendors etc have appeared. What does this really mean for CRM software? Is it Dead or Alive? Listen to Mark’s view from Oracle and its customers.                  Location- Westbourne 2, Level –1. Also stop by the Oracle booth at the demogrounds.  The event looks promising with some great content from the Gartner analysts and from what the Gartner folks just told me, the event is oversold. And the weather in London town? As expected…slight showers on Monday with a high of 49 degrees F and partly cloudy on Tuesday, with a high of 50 degrees F.

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• Step Aside Google

  - by David Dorf

  Step aside Google. While search will always be a huge part of the web, I can see a day in the not-too-distance future where search takes a backseat to the social graph. Links between pages will give way to relationships between people, including context like location. What does this mean for retail? It means your e-commerce strategy will slowly transition to an f-commerce strategy. Remember when a large portion of the online population was held captive inside the walls of AOL? All the commercials listed an AOL keyword, not a web address because that's where the majority of people surfed. Now, people are spending a huge amount of time in Facebook (despite Betty White's proclamation that its a big waste of time). According to Facebook, users spend 500 billion minutes per month on the site. Selling products where consumers are spending their time makes sense. The power of Like and Share are the most effective approach to marketing. More and more stores are popping up on Facebook, and soon they will be the front-end to e-commerce systems. As sites adopt the Facebook Open Graph API, users will have a harder time distinguishing the open web from their Facebook experience, including shopping. Of course e-commerce sites won't go away, but a large portion of their traffic will emanate from Facebook and in some cases Facebook will act as the front-end for the web store. Ignore Facebook Open Graph at your peril. In a Mashable article, Mitchell Harper made several predictions about how e-commerce will change based on Facebook. His five points are not far-fetched at all, so we need to watch this space carefully.

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• Favorite Programmer Quotes…

  - by SGWellens

    "A computer once beat me at chess, but it was no match for me at kick boxing." — Emo Philips   "There are only 10 types of people in the world, those who understand binary and those who don't. " – Unknown.   "Premature optimization is the root of all evil." — Donald Knuth   "I should have become a doctor; then I could bury my mistakes." — Unknown   "Code softly and carry a large backup thumb drive." — Me   "Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live." — Martin Golding   "DDE…the protocol from hell"— Charles Petzold   "Just because a thing is new don't mean that it's better" — Will Rogers   "The mark of a mature programmer is willingness to throw out code you spent time on when you realize it's pointless." — Bram Cohen   "A good programmer is someone who looks both ways before crossing a one-way street." — Doug Linder   "The early bird may get the worm but it's the second mouse that gets the cheese." — Unknown   I hope someone finds this amusing. Steve Wellens CodeProject

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• The How-To Geek Valentine’s Day Gift Guide

  - by Jason Fitzpatrick

  Valentine’s Day is less than week away; if you want to prove yourself the geekiest cupid around you’ll definitely want to check out our guide to geeky Valentine’s big and small. The following gift guide includes gifts for the geeks in your life and gifts for geeks to give those that appreciate their geeky nature. Our methodology for picking Valentine’s-related gifts focused on gifts that were either traditional Valentine’s day gifts with a geek-slant or a nod to an aspect of geek culture. Read on to check out the geektacular pickings we mined the internet to unearth. Latest Features How-To Geek ETC The How-To Geek Valentine’s Day Gift Guide Inspire Geek Love with These Hilarious Geek Valentines RGB? CMYK? Alpha? What Are Image Channels and What Do They Mean? How to Recover that Photo, Picture or File You Deleted Accidentally How To Colorize Black and White Vintage Photographs in Photoshop How To Get SSH Command-Line Access to Windows 7 Using Cygwin View the Cars of Tomorrow Through the Eyes of the Past [Historical Video] Add Romance to Your Desktop with These Two Valentine’s Day Themes for Windows 7 Gmail’s Priority Inbox Now Available for Mobile Web Browsers Touchpad Blocker Locks Down Your Touchpad While Typing Arrival of the Viking Fleet Wallpaper A History of Vintage Transformers [Infographic]

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• The Best Tips and Tweaks for Getting the Most Out of Internet Explorer 9

  - by Lori Kaufman

  If you use Internet Explorer 9, we have many tips and tricks for you to improve your web surfing experience, from customizing the interface to using the many features, and to make your time online more secure with IE9’s many security and privacy enhancements. Surf or Search Using the One Box (Address Bar) In IE versions prior to 9, the address bar and search bar were separate. They are now combined into the One Box in IE9, allowing you to navigate to websites or start a search from a single place. According to Microsoft, if you enter a single word that represents a valid URL, such as “microsoft” or “howtogeek,” the word will be evaluated as a URL and you can click on the URL or press Shift + Enter to load that site. The One Box also provides inline autocomplete functionality, so you only have to type a few letters to quickly get to your favorite sites. IE9 autocompletes what you are typing with popular websites, as well as with items from your Favorites and History lists. HTG Explains: What Is Windows RT and What Does It Mean To Me? HTG Explains: How Windows 8′s Secure Boot Feature Works & What It Means for Linux Hack Your Kindle for Easy Font Customization

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• stress testing opencl/Ati GPU on 12.04

  - by lurscher

  What does people normally use to stress test their GPU on ubuntu 12.04? I tried installing Phoronix Benchmark suite ubuntu .deb but it tries to install freeglu3-dev and at the same time complains about $ phoronix-test-suite benchmark pts/opencl The following dependencies are needed and will be installed: freeglut3-dev This process may take several minutes. Reading package lists... Building dependency tree... Reading state information... freeglut3-dev is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 90 not upgraded. There are dependencies still missing from the system: - OpenGL Utility Kit / GLUT 1: Ignore missing dependencies and proceed with installation. 2: Skip installing the tests with missing dependencies. 3: Re-attempt to install the missing dependencies. 4: Quit the current Phoronix Test Suite process. Missing dependencies action: 4 so even if it is installing freeglu3, it still complains about missing GLUT. You can't win against GLUT it seems So, what does people use for this? i mean, really, because i have tried googling for an hour and it is not paying up Thanks!

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• Should we enforce code style in our large codebase?

  - by eighttrackmind

  By "code style" I mean 2 things: Style, eg. // bad if(foo){ ... } // good if (foo) { ... } Conventions and idiomaticity, where two ways of writing the same thing are functionally equivalent, but one is more idiomatic. eg. // bad if (fooLib.equals(a, b)) { ... } // good if (a == b) { ... } I think it makes sense to use an auto-formatter to enforce #1 automatically. So my question is specifically about #2. I like to break things down into pros and cons, here's what I've come up with so far: Pros: Used by many large codebases (eg. Google, jQuery) Helps make it a bit easier to work on new areas of the codebase Helps make code more portable (this is not necessarily true) Code style is automatic once you get used to it Makes it easier to fast-decline pull requests Cons: Takes engineers’ and code reviewers’ time away from more important things (like developing features) Code should ideally be rewritten every 2-3 years anyway, so it’s more important to focus on getting the architecture right, and achieving high test coverage Adds strain to code reviews (eg. “don’t do it this way, I like this other way better”) Even if I’ve been using a code style for a while, I still sometime have to pause and think about how to write a line better Having an enforced, uniform code style makes it hard to experiment with potentially better styles Maintaining a style guide takes a lot of incremental effort Engineers rarely read through the style guide. More often, it's cited in code reviews And as a secondary question: we also have many smaller repositories - should the same code style be enforced there?

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• Geek it Up

  - by BuckWoody

  I’ve run into a couple of kinds of folks in IT. Some really like technology a lot – a whole lot –and others treat it more as a job. For those of you in the second camp, you can go back to your drab, meaningless jobs – this post is for the first group. I’m a geek. Not a little bit of a geek, a really big one. I love technology, I get excited about science and electronics in general, and I read math books when I don’t have to. Yes, I have a Star Trek item or two around the house. My daughter is fluent in both Monty Python AND Serenity. I totally admit it. So if you’re like me (OK, maybe a little less geeky than that), then go for it. Put those toys in your cubicle, wear your fan shirt, but most of all, geek up your tools. No, this isn’t an April Fool’s post – I really mean it. I’ve noticed that when I get the larger monitor, better mouse, cooler keyboard, I LIKE coming to work. It’s a way to reward yourself – I’ve even found that it makes work easier if I have the kind of things I enjoy around to work with. So buy that old “clicky” IBM keyboard, get three monitors, and buy a nice headset so that you can set all of your sounds to Monty Python WAV’s. And get to work. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Can static methods be called using object/instance in .NET

  Ans is Yes and No   Yes in C++, Java and VB.NET No in C#   This is only compiler restriction in c#. You might see in some websites that we can break this restriction using reflection and delegates, but we can’t, according to my little research J I shall try to explain you…   Following is code sample to break this rule using reflection, it seems that it is possible to call a static method using an object, p1 using System; namespace T {     class Program     {         static void Main()         {             var p1 = new Person() { Name = "Smith" };             typeof(Person).GetMethod("TestStatMethod").Invoke(p1, new object[] { });                     }         class Person         {             public string Name { get; set; }             public static void TestStatMethod()             {                 Console.WriteLine("Hello");             }         }     } } but I do not think so this method is being called using p1 rather Type Name “Person”. I shall try to prove this… look at another example…  Test2 has been inherited from Test1. Let’s see various scenarios… Scenario1 using System; namespace T {     class Program     {         static void Main()         {             Test1 t = new Test1();            typeof(Test2).GetMethod("Method1").Invoke(t,                                  new object[] { });         }     }     class Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method1");         }     }       class Test2 : Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method2");         }     } } Output:   At test1::Method2 Scenario2         static void Main()         {             Test2 t = new Test2();            typeof(Test2).GetMethod("Method1").Invoke(t,                                          new object[] { });         }   Output:   At test1::Method2   Scenario3         static void Main()         {             Test1 t = new Test2();            typeof(Test2).GetMethod("Method1").Invoke(t,                             new object[] { });         }   Output: At test1::Method2 In all above scenarios output is same, that means, Reflection also not considering the object what you pass to Invoke method in case of static methods. It is always considering the type which you specify in typeof(). So, what is the use passing instance to “Invoke”. Let see below sample using System; namespace T {     class Program     {         static void Main()         {            typeof(Test2).GetMethod("Method1").                Invoke(null, new object[] { });         }     }       class Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method1");         }     }     class Test2 : Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method2");         }     } }   Output is   At test1::Method2   I was able to call Invoke “Method1” of Test2 without any object.  Yes, there no wonder here as Method1 is static. So we may conclude that static methods cannot be called using instances (only in c#) Why Microsoft has restricted it in C#? Ans: Really there Is no use calling static methods using objects because static methods are stateless. but still Java and C++ latest compilers allow calling static methods using instances. Java sample class Test {      public static void main(String str[])      {            Person p = new Person();            System.out.println(p.GetCount());      } }   class Person {   public static int GetCount()   {      return 100;   } }   Output          100 span.fullpost {display:none;}

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• Slide-decks from recent Adelaide SQL Server UG meetings

  - by Rob Farley

  The UK has been well represented this summer at the Adelaide SQL Server User Group, with presentations from Chris Testa-O’Neill (isn’t that the right link? Maybe try this one) and Martin Cairney. The slides are available here and here. I thought I’d particularly mention Martin’s, and how it’s relevant to this month’s T-SQL Tuesday. Martin spoke about Policy-Based Management and the Enterprise Policy Management Framework – something which is remarkably under-used, and yet which can really impact your ability to look after environments. If you have policies set up, then you can easily test each of your SQL instances to see if they are still satisfying a set of policies as defined. Automation (the topic of this month’s T-SQL Tuesday) should mean that your life is made easier, thereby enabling to you to do more. It shouldn’t remove the human element, but should remove (most of) the human errors. People still need to manage the situation, and work out what needs to be done, etc. We haven’t reached a point where computers can replace people, but they are very good at replace the mundaneness and monotony of our jobs. They’ve made our lives more interesting (although many would rightly argue that they have also made our lives more complex) by letting us focus on the stuff that changes. Martin named his talk Put Your Feet Up, which nicely expresses the fact that managing systems shouldn’t be about running around checking things all the time. It must be about having systems in place which tell you when things aren’t going well. It’s never quite as simple as being able to actually put your feet up, but certainly no system should require constant attention. It’s definitely a policy we at LobsterPot adhere to, whether it’s an alert to let us know that an ETL package has run successfully, or a script that generates some code for a report. If things can be automated, it reduces the chance of error, reduces the repetitive nature of work, and in general, keeps both consultants and clients much happier.

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• Imperative vs. LINQ Performance on WP7

  - by Bil Simser

  Jesse Liberty had a nice post presenting the concepts around imperative, LINQ and fluent programming to populate a listbox. Check out the post as it’s a great example of some foundational things every .NET programmer should know. I was more interested in what the IL code that would be generated from imperative vs. LINQ was like and what the performance numbers are and how they differ. The code at the instruction level is interesting but not surprising. The imperative example with it’s creating lists and loops weighs in at about 60 instructions. .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } 1: .method private hidebysig instance void ImperativeMethod() cil managed 2: { 3: .maxstack 3 4: .locals init ( 5: [0] class [mscorlib]System.Collections.Generic.IEnumerable`1<int32> someData, 6: [1] class [mscorlib]System.Collections.Generic.List`1<int32> inLoop, 7: [2] int32 n, 8: [3] class [mscorlib]System.Collections.Generic.IEnumerator`1<int32> CS$5$0000, 9: [4] bool CS$4$0001) 10: L_0000: nop 11: L_0001: ldc.i4.1 12: L_0002: ldc.i4.s 50 13: L_0004: call class [mscorlib]System.Collections.Generic.IEnumerable`1<int32> [System.Core]System.Linq.Enumerable::Range(int32, int32) 14: L_0009: stloc.0 15: L_000a: newobj instance void [mscorlib]System.Collections.Generic.List`1<int32>::.ctor() 16: L_000f: stloc.1 17: L_0010: nop 18: L_0011: ldloc.0 19: L_0012: callvirt instance class [mscorlib]System.Collections.Generic.IEnumerator`1<!0> [mscorlib]System.Collections.Generic.IEnumerable`1<int32>::GetEnumerator() 20: L_0017: stloc.3 21: L_0018: br.s L_003a 22: L_001a: ldloc.3 23: L_001b: callvirt instance !0 [mscorlib]System.Collections.Generic.IEnumerator`1<int32>::get_Current() 24: L_0020: stloc.2 25: L_0021: nop 26: L_0022: ldloc.2 27: L_0023: ldc.i4.5 28: L_0024: cgt 29: L_0026: ldc.i4.0 30: L_0027: ceq 31: L_0029: stloc.s CS$4$0001 32: L_002b: ldloc.s CS$4$0001 33: L_002d: brtrue.s L_0039 34: L_002f: ldloc.1 35: L_0030: ldloc.2 36: L_0031: ldloc.2 37: L_0032: mul 38: L_0033: callvirt instance void [mscorlib]System.Collections.Generic.List`1<int32>::Add(!0) 39: L_0038: nop 40: L_0039: nop 41: L_003a: ldloc.3 42: L_003b: callvirt instance bool [mscorlib]System.Collections.IEnumerator::MoveNext() 43: L_0040: stloc.s CS$4$0001 44: L_0042: ldloc.s CS$4$0001 45: L_0044: brtrue.s L_001a 46: L_0046: leave.s L_005a 47: L_0048: ldloc.3 48: L_0049: ldnull 49: L_004a: ceq 50: L_004c: stloc.s CS$4$0001 51: L_004e: ldloc.s CS$4$0001 52: L_0050: brtrue.s L_0059 53: L_0052: ldloc.3 54: L_0053: callvirt instance void [mscorlib]System.IDisposable::Dispose() 55: L_0058: nop 56: L_0059: endfinally 57: L_005a: nop 58: L_005b: ldarg.0 59: L_005c: ldfld class [System.Windows]System.Windows.Controls.ListBox PerfTest.MainPage::LB1 60: L_0061: ldloc.1 61: L_0062: callvirt instance void [System.Windows]System.Windows.Controls.ItemsControl::set_ItemsSource(class [mscorlib]System.Collections.IEnumerable) 62: L_0067: nop 63: L_0068: ret 64: .try L_0018 to L_0048 finally handler L_0048 to L_005a 65: } 66:   67: Compare that to the IL generated for the LINQ version which has about half of the instructions and just gets the job done, no fluff. .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } 1: .method private hidebysig instance void LINQMethod() cil managed 2: { 3: .maxstack 4 4: .locals init ( 5: [0] class [mscorlib]System.Collections.Generic.IEnumerable`1<int32> someData, 6: [1] class [mscorlib]System.Collections.Generic.IEnumerable`1<int32> queryResult) 7: L_0000: nop 8: L_0001: ldc.i4.1 9: L_0002: ldc.i4.s 50 10: L_0004: call class [mscorlib]System.Collections.Generic.IEnumerable`1<int32> [System.Core]System.Linq.Enumerable::Range(int32, int32) 11: L_0009: stloc.0 12: L_000a: ldloc.0 13: L_000b: ldsfld class [System.Core]System.Func`2<int32, bool> PerfTest.MainPage::CS$<>9__CachedAnonymousMethodDelegate6 14: L_0010: brtrue.s L_0025 15: L_0012: ldnull 16: L_0013: ldftn bool PerfTest.MainPage::<LINQProgramming>b__4(int32) 17: L_0019: newobj instance void [System.Core]System.Func`2<int32, bool>::.ctor(object, native int) 18: L_001e: stsfld class [System.Core]System.Func`2<int32, bool> PerfTest.MainPage::CS$<>9__CachedAnonymousMethodDelegate6 19: L_0023: br.s L_0025 20: L_0025: ldsfld class [System.Core]System.Func`2<int32, bool> PerfTest.MainPage::CS$<>9__CachedAnonymousMethodDelegate6 21: L_002a: call class [mscorlib]System.Collections.Generic.IEnumerable`1<!!0> [System.Core]System.Linq.Enumerable::Where<int32>(class [mscorlib]System.Collections.Generic.IEnumerable`1<!!0>, class [System.Core]System.Func`2<!!0, bool>) 22: L_002f: ldsfld class [System.Core]System.Func`2<int32, int32> PerfTest.MainPage::CS$<>9__CachedAnonymousMethodDelegate7 23: L_0034: brtrue.s L_0049 24: L_0036: ldnull 25: L_0037: ldftn int32 PerfTest.MainPage::<LINQProgramming>b__5(int32) 26: L_003d: newobj instance void [System.Core]System.Func`2<int32, int32>::.ctor(object, native int) 27: L_0042: stsfld class [System.Core]System.Func`2<int32, int32> PerfTest.MainPage::CS$<>9__CachedAnonymousMethodDelegate7 28: L_0047: br.s L_0049 29: L_0049: ldsfld class [System.Core]System.Func`2<int32, int32> PerfTest.MainPage::CS$<>9__CachedAnonymousMethodDelegate7 30: L_004e: call class [mscorlib]System.Collections.Generic.IEnumerable`1<!!1> [System.Core]System.Linq.Enumerable::Select<int32, int32>(class [mscorlib]System.Collections.Generic.IEnumerable`1<!!0>, class [System.Core]System.Func`2<!!0, !!1>) 31: L_0053: stloc.1 32: L_0054: ldarg.0 33: L_0055: ldfld class [System.Windows]System.Windows.Controls.ListBox PerfTest.MainPage::LB2 34: L_005a: ldloc.1 35: L_005b: callvirt instance void [System.Windows]System.Windows.Controls.ItemsControl::set_ItemsSource(class [mscorlib]System.Collections.IEnumerable) 36: L_0060: nop 37: L_0061: ret 38: } Again, not surprising here but a good indicator that you should consider using LINQ where possible. In fact if you have ReSharper installed you’ll see a squiggly (technical term) in the imperative code that says “Hey Dude, I can convert this to LINQ if you want to be c00L!” (or something like that, it’s the 2010 geek version of Clippy). What about the fluent version? As Jon correctly pointed out in the comments, when you compare the IL for the LINQ code and the IL for the fluent code it’s the same. LINQ and the fluent interface are just syntactical sugar so you decide what you’re most comfortable with. At the end of the day they’re both the same. Now onto the numbers. Again I expected the imperative version to be better performing than the LINQ version (before I saw the IL that was generated). Call it womanly instinct. A gut feel. Whatever. Some of the numbers are interesting though. For Jesse’s example of 50 items, the numbers were interesting. The imperative sample clocked in at 7ms while the LINQ version completed in 4. As the number of items went up, the elapsed time didn’t necessarily climb exponentially. At 500 items they were pretty much the same and the results were similar up to about 50,000 items. After that I tried 500,000 items where the gap widened but not by much (2.2 seconds for imperative, 2.3 for LINQ). It wasn’t until I tried 5,000,000 items where things were noticeable. Imperative filled the list in 20 seconds while LINQ took 8 seconds longer (although personally I wouldn’t suggest you put 5 million items in a list unless you want your users showing up at your door with torches and pitchforks). Here’s the table with the full results. Method/Items 50 500 5,000 50,000 500,000 5,000,000 Imperative 7ms 7ms 38ms 223ms 2230ms 20974ms LINQ/Fluent 4ms 6ms 41ms 240ms 2310ms 28731ms Like I said, at the end of the day it’s not a huge difference and you really don’t want your users waiting around for 30 seconds on a mobile device filling lists. In fact if Windows Phone 7 detects you’re taking more than 10 seconds to do any one thing, it considers the app hung and shuts it down. The results here are for Windows Phone 7 but frankly they're the same for desktop and web apps so feel free to apply it generally. From a programming perspective, choose what you like. Some LINQ statements can get pretty hairy so I usually fall back with my simple mind and write it imperatively. If you really want to impress your friends, write it old school then let ReSharper do the hard work for! Happy programming!

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• Is duck typing a subset of polymorphism

  - by Raynos

  From Polymorphism on WIkipedia In computer science, polymorphism is a programming language feature that allows values of different data types to be handled using a uniform interface. From duck typing on Wikipedia In computer programming with object-oriented programming languages, duck typing is a style of dynamic typing in which an object's current set of methods and properties determines the valid semantics, rather than its inheritance from a particular class or implementation of a specific interface. My interpretation is that based on duck typing, the objects methods/properties determine the valid semantics. Meaning that the objects current shape determines the interface it upholds. From polymorphism you can say a function is polymorphic if it accepts multiple different data types as long as they uphold an interface. So if a function can duck type, it can accept multiple different data types and operate on them as long as those data types have the correct methods/properties and thus uphold the interface. (Usage of the term interface is meant not as a code construct but more as a descriptive, documenting construct) What is the correct relationship between ducktyping and polymorphism ? If a language can duck type, does it mean it can do polymorphism ?

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• CodePlex Daily Summary for Thursday, October 27, 2011

  CodePlex Daily Summary for Thursday, October 27, 2011Popular ReleasesAcDown????? - Anime&Comic Downloader: AcDown????? v3.6: ?? ● AcDown??????????、??????，??????????????????????，???????Acfun、Bilibili、???、???、???、Tucao.cc、SF???、?????80????，???????????、?????????。 ● AcDown???????????????????????????，???，???????????????????。 ● AcDown???????C#??，????.NET Framework 2.0??。?????"Acfun?????"。 ????32??64? Windows XP/Vista/7 ????????????? ??：????????Windows XP???,?????????.NET Framework 2.0???(x86)?.NET Framework 2.0???(x64)，?????"?????????"??? ??????????????，??????????： ??"AcDown?????"????????? ?? v3.6?? ??“????”...Facebook C# SDK: 5.3.1: This is a BETA release which adds new features and bug fixes to v5.2.1. removed dependency from Code Contracts enabled Task Parallel Support in .NET 4.0+ added support for early preview for .NET 4.5 added additional method overloads for .NET 4.5 to support IProgress<T> for upload progress added new CS-WinForms-AsyncAwait.sln sample demonstrating the use of async/await, upload progress report using IProgress<T> and cancellation support Query/QueryAsync methods uses graph api instead...SQL Backup Helper: SQL Backup Helper v1.0: Version 1.0 Changes Description added to settings table Automatic LOG files truncation added to BACKUP stored procedure Only database in status ONLINE will be backed upFlowton: Release 0.2: This release is the first official release of Flowton along with Source. Printpreview/Print is enabled with minor bug fixes from 0.1 alpha release locally.MySemanticSearch Sample: MySemanticSearch Installer (CTP3): Note: This release of the MySemanticSearch Sample works with SQL Server 2012 CTP3. Installation InstructionsDownload this self-extracting archive to your computer Execute the self-extracting archive Accept the licensing agreement Choose a target directory on your computer and extract the files Open Windows PowerShell command prompt with elevated priveleges Execute the following command: Set-ExecutionPolicy Unrestricted Close the Windows PowerShell command prompt Run C:\MySema...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.33: Add JSParser.ParseExpression method to parse JavaScript expressions rather than source-elements. Add -strict switch (CodeSettings.StrictMode) to force input code to ECMA5 Strict-mode (extra error-checking, "use strict" at top). Fixed bug when MinifyCode setting was set to false but RemoveUnneededCode was left it's default value of true.Path Copy Copy: 8.0: New version that mostly adds lots of requested features: 11340 11339 11338 11337 This version also features a more elaborate Settings UI that has several tabs. I tried to add some notes to better explain the use and purpose of the various options. The Path Copy Copy documentation is also on the way, both to explain how to develop custom plugins and to explain how to pre-configure options if you're a network admin. Stay tuned.MVC Controls Toolkit: Mvc Controls Toolkit 1.5.0: Added: The new Client Blocks feaure of Views A new "move" js method for the TreeViews The NewHtmlCreated js event to the DataGrid Improved the ChoiceList structure that now allows also the selection list of a dropdown to be chosen with a lambda expression Fixed: Issue with partial thrust Client handling of conditional attributes Bug in TreeView node moves that sometimes were not reflected on the server An issue in the Mvc3 Nuget package that wasn't able to uninstall properly ...Free SharePoint Master Pages: Buried Alive (Halloween) Theme: Release Notes *Created for Halloween, you will find theme file, custom css file and images. *Created by Al Roome @AlstarRoome Features: Custom styling for web part Custom background *Screenshot https://s3.amazonaws.com/kkhipple/post/sharepoint-showcase-halloween.pngDevForce Application Framework: DevForce AF 2.0.3 RTW: PrerequisitesWPF 4.0 Silverlight 4.0 DevForce 2010 6.1.3.1 Download ContentsDebug and Release Assemblies API Documentation Source code License.txt Requirements.txt Release HighlightsNew: EventAggregator event forwarding New: EntityManagerInterceptor<T> to intercept EntityManger events New: IHarnessAware to allow for ViewModel setup when executed inside of the Development Harness New: Improved design time stability New: Support for add-in development New: CoroutineFns.To...NicAudio: NicAudio 2.0.5: Minor change to accept special DTS stereo modes (LtRt, AB,...)Windows Azure Toolkit for Windows Phone: Windows Azure Toolkit for Windows Phone v1.3.1: Upgraded Windows Azure projects to Windows Azure Tools for Microsoft Visual Studio 2010 1.5 – September 2011 Upgraded the tools tools to support the Windows Phone Developer Tools RTW Update SQL Azure only scenarios to use ASP.NET Universal Providers (through the System.Web.Providers v1.0.1 NuGet package) Changed Shared Access Signature service interface to support more operations Refactored Blobs API to have a similar interface and usage to that provided by the Windows Azure SDK Stor...xUnit.net Contrib: xunitcontrib-resharper 0.4.4 (dotCover): xunitcontrib release 0.4.4 (ReSharper runner) This release provides a test runner plugin for Resharper 6.0 RTM, targetting all versions of xUnit.net. (See the xUnit.net project to download xUnit.net itself.) This release addresses the following issues:Support for dotCover code coverage 4132 Note that this build work against ALL VERSIONS of xunit. The files are compiled against xunit.dll 1.8 - DO NOT REPLACE THIS FILE. Thanks to xunit's version independent runner system, this package can r...BookShop: BookShop: BookShop WP7 clientRibbon Editor for Microsoft Dynamics CRM 2011: Ribbon Editor (0.1.2122.266): Added CodePlex and PayPal links New icon Bug fix: can't connect to an IFD deployment when the discovery service url has been customizedSiteMap Editor for Microsoft Dynamics CRM 2011: SiteMap Editor (1.0.921.340): Added CodePlex and PayPal links New iconDotNet.Framework.Common: DotNet.Framework.Common 4.0: ??????????，????????????XML Explorer: XML Explorer 4.0.5: Changes in 4.0.5: Added 'Copy Attribute XPath to Address Bar' feature. Added methods for decoding node text and value from Base64 encoded strings, and copying them to the clipboard. Added 'ChildNodeDefinitions' to the options, which allows for easier navigation of parent-child and ID-IDREF relationships. Discovery happens on-demand, as nodes are expanded and child nodes are added. Nodes can now have 'virtual' child nodes, defined by an xpath to select an identifier (usually relative to ...CODE Framework: 4.0.11021.0: This build adds a lot of our WPF components, including our MVVC and MVC components as well as a "Metro" and "Battleship" style.WiX Toolset: WiX v3.6 Beta: First beta release of WiX v3.6. The primary focus is on Burn but there are also many small bug fixes to the core toolset. For more information see: http://robmensching.com/blog/posts/2011/10/24/WiX-v3.6-Beta-releasedNew Projects5by5by4 Tic Tac Toe Project: 5by5by4 Tic Tac Toe project for CS 3420.ASP.Net Membership provider for MongoDb: A role and membership provider for ASP.Net with MongoDb as the database. Makes use of the Norm Linq provider for MongoDb.Bazookabird TFS Dashboard: Just a simple TFS dashboard. Show build results, tfs queries of your choice and display availability of build machines. Only a feature-lacking proof of concept yet, will hopefully be useful in the end. BestWebApp: Web service and web application.Code Made Simple: A group of projects to make coding life simple.DefenseXna: ??xna??Digibib.NET: Digibib.NET ist eine Portierung der Lesesoftware Digibux für die Digitale Bibliothek der Directmedia Publishing.FaceComparerDistributed: project of face compare distributed versionFMSSolution: FMSISO Analyzer: ISO Analyzer is a tool that makes it easier to analyze ISO 8583 financial transactions and also provides a platform to create a host simulator, capable of receiving requests and sending back the responses. It’s a WinForms application and it’s developed using C#.ITU Project: ITU Projekt - Víc než len klávesové skratky (navigace mezi bežicími aplikacemi)Maintenance Province Data: Help people find your project. Write a concise, reader-focused summary. Example: <project name> makes it easier for <target user group> to <activity>. You'll no longer have to <activity>. It's developed in <programming language>.m?ng chia s? công vi?c: m?ng chia s? công vi?cMetroTask: MetroTask, An example Metro based application using C#MyHomeFinance: Helps to add and keep a record of financeMySemanticSearch Sample: MySemanticSearch is a sample content management application that demonstrates semantic search capabilities introduced in SQL Server 2012. MySemanticSearch allows you to visualize tag clouds for content stored in FileTables and find similar content using semantic search.NetBlocks: This project is an implementation of the Unit-of-Work and Repository patterns using Entity Framework 4.1 and Unity. The project also includes code that can be used to initialize an application’s run-time environment from a set of components. The project includes example components for typed configuration settings, caching and a factory component based on Unity. Also included is an example of how to represent a database command with a C# class that transforms the results to typed objects.Online shopping website in ASP.NET- Open Source Project: asp.net,C#,shopping cart,college project,visual studio 2010,visual web developer 2010Pak Master: Pak Explorer for the fourth coming four.Pizza Service: A mvc3 project which aims to host both a backend webservice and a frontend page for ordering pizza and managing orders, customers and provide a drivermapScadaEveryWhere: ScadaEveryWhereSilverTwitterSearch: SilverTwitterSearch is a Siliverlight library for the Twitter Search API.Snst Salix: Salix is codename for custom solution of time management and task assignment software.SolutionManagementKit: SolutionManagementKit This product will try to combine several monitoring / support tools available right now. the primary focus will be on (T) SQL / MDX parsing for SQL 2008 R2 SSAS 2008 R2 as well as cube maintance Development in C# / VB .NETTarget: Blank Orchard Module: If enabled, outgoing links open in new window (just like with the deprecated target="_blank" attribute)WPPersonality: Psychological tests for windows phoneXrmLibrary: A base library to be used for rapid integration with one or more Microsoft Dynamics CRM 2011 environments. The XrmLibrary contains thread-safe singleton implementations of both the CRM IOrganizationService (1 or many instances) and a tracer/logger that utilizes Apache's log4net.

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• How to run 'apt-get install' to install all dependencies?

  - by michael

  I am running this in ubuntu server installation: sudo apt-get install git-core gnupg flex bison gperf build-essential \ zip curl libc6-dev libncurses5-dev:i386 x11proto-core-dev \ libx11-dev:i386 libreadline6-dev:i386 libgl1-mesa-glx:i386 \ libgl1-mesa-dev g++-multilib mingw32 openjdk-6-jdk tofrodos \ python-markdown libxml2-utils xsltproc zlib1g-dev:i386 but I am getting this: Reading package lists... Building dependency tree... Reading state information... curl is already the newest version. gnupg is already the newest version. Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: build-essential : Depends: gcc (>= 4:4.4.3) but it is not going to be installed Depends: g++ (>= 4:4.4.3) but it is not going to be installed g++-multilib : Depends: cpp (>= 4:4.7.2-1ubuntu2) but it is not going to be installed Depends: gcc-multilib (>= 4:4.7.2-1ubuntu2) but it is not going to be installed Depends: g++ (>= 4:4.7.2-1ubuntu2) but it is not going to be installed Depends: g++-4.7-multilib (>= 4.7.2-1~) but it is not going to be installed How can I fix this?

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• Begin the Clone Wars Have!

  - by Antony Reynolds

  Creating a New Virtual Machine from an Existing Virtual Disk In previous posts I described how I set up an OEL6 machine under VirtualBox that can run an 11gR2 database and FMW 11.1.1.5.  That is great if you want the DB and FMW running in the same virtual image and it has served me well for some proof of concepts and also for some testing of different JVMs.  However I also wanted to run some testing of FMW with the database running on a separate physical machine.  So in this post I will show how to take a VirtualBox image and create a new image based on the disks from that original image. What are my Options? There is more than one way to skin a cat, or in this case to create two separate VMs that can run on different hardware.  Some of the options include: Create new virtual disk images for each new VM. Clone the existing disk images and point the new VM at the cloned images. Point the new VM at the existing snapshots. #1 is too much like hard work, install OEL twice, install a database again, install FMW again, run RCU again!  Life is too short! #2 is probably the safest way of doing things.  VirtualBox allows you to clone a disk image for use in a separate machine.  However this of course duplicates the disk and means that it is now occupying 3 times the space, once for the original disk and twice more for the two clones I would need. #3 is the most space efficient way of doing things.  It does mean however that I can only run the new “cloned” images if I have access to the original image because that is where the base snapshots reside.  However this is not a problem for me as long as I remember to keep all threee images together.  So this is the approach we will follow. Snapshot, What Snapshot? As we are going to create new virtual machines based on existing snapshots we need to figure out which snapshot to use.  We do this by opening the “Media Manager” from within VirtualBox and moving the mouse over the snapshot images until we find the snapshots we want – the snapshot name is identified in the “Attached to:” comment.  In my case I wanted the FMW installed snapshot because that had a database configured for FMW alongside the FMW software.  I made a note of the filename of that snapshot (actually I just noted the first 5 characters as that was all that was needed to uniquely identify the snapshot file). When we create the new machines we will point them at the snapshot filename we have just checked. Network or NotWork? Because we want the two new machines to communicate with each other when hosted in different physical machines we can’t use the default NAT networking mode without a lot of hassle.  But at the same time we need them to have fixed IP addresses relative to each other so that they can see each other whilst also being able to see the outside world. To achieve all these requirements I created two network adapters for each machine.  Adapter 1 was a standard NAT mapping.  This will allow each machine to get a dynamic IP address (10.0.2.15 by default) that can be used to access the external world through the VBox provided NAT gateway.  This is the same as the existing configuration. The second adapter I created as a bridged adapter.  This gives the virtual machine direct access to the host network card and by using fixed IP addresses each machine can see the other.  It is important to choose fixed IP addresses that are not routable across your internal network so you don’t get any clashes with other machines on your network.  Of course you could always get proper fixed IP addresses from your network people, but I have serveral people using my images and as long as I don’t have two instances of the same VM on the same network segment this is easier and avoids reconfiguring the network every time someone wants a copy of my VM.  If it is available I would suggest using the 10.0.3.* network as 10.0.2.* is the default NAT network.  You can check availability by pinging 10.0.3.1 and 10.0.3.2 from your host machine.  If it times out then you are probably safe to use that. Creating the New VMs Now that I had collected the data that I needed I went ahead and created the new VMs. When asked for a “Boot Hard Disk” I used the “Choose a virtual hard disk file…” link to find the snapshot I had previously selected and set that to be the existing hard disk.  I chose the previously existing SOA 11.1.1.5 install for both the new DB and FMW machines because that snapshot had the database with the RCU completed that I wanted for my DB machine and it had the SOA software installed which I wanted for my FMW machine. After the initial creation of the virtual machine go into the network setting section and enable a second adapter which will be bridged.  Make a note of the MAC addresses (the last four digits should be sufficient) of the two adapters so that you can later set the bridged adapter to use fixed IP and the NAT adapter to use DHCP. We are now ready to start the VMs and reconfigure Linux. Reconfiguring Linux Because I now have two new machines I need to change their network configuration.  In particular I need to change the hostname, update the hosts file and change the network settings. Changing the Hostname I renamed both hosts by running the hostname command as root: hostname vboxfmw.oracle.com I also edited the /etc/sysconfig file and set the correct hostname in there. HOSTNAME=vboxfmw.oracle.com Changing the Network Settings I needed to change the network configuration to give the bridged network a fixed IP address.  I first explicitly set the MAC addresses of the two adapters, because the order of the virtual adapters in the VirtualBox Manager is not necessarily the same as the order of the adapters in the guest OS.  So I went in to the System->Preferences->Network Connections screen and explicitly set the “Device MAC address” for the two adapters. Having correctly mapped the Linux adapters to the VirtualBox adapters I then set the Bridged adapter to use fixed IP addressing rather than DHCP.  There is no need for additional routing or default gateways because we expect the two machine to be on the same LAN segment. Updating the Hosts File Having renamed the machines and reconfigured the network I then updated the /etc/hosts file to refer to the new machine name add a new line to the hosts file to provide an additional IP address for my server (the new fixed IP address) add a new line for the fixed IP address of the other virtual machine 10.0.3.101      vboxdb.oracle.com       vboxdb  # Added by NetworkManager 10.0.2.15       vboxdb.oracle.com       vboxdb  # Added by NetworkManager 10.0.3.102      vboxfmw.oracle.com      vboxfmw # Added by NetworkManager 127.0.0.1       localhost.localdomain   localhost ::1     vboxdb.oracle.com       vboxdb  localhost6.localdomain6 localhost6 To make sure everything takes effect I restarted the server. Reconfiguring the Database on the DB Machine Because we changed the hostname the listener and the EM console no longer start so I need to modify the listener.ora to use the new hostname and I also need to rebuild the EM configuration because it also relies on the hostname. I edited the $ORACLE_HOME/network/admin/listener.ora and changed the listening address to the new hostname:       (ADDRESS = (PROTOCOL = TCP)(HOST = vboxdb.oracle.com)(PORT = 1521)) After changing the listener.ora I was able to start the listener using: lsnrctl start I also had to reconfigure the EM database control.  I first deconfigured it using the command: emca -deconfig dbcontrol db -repos drop This drops the repository and removes any existing registered dbcontrols. I then re-configured it using the following command: emca -config dbcontrol db -repos create This creates the EM repository and then configures and starts dbcontrol. Now my database machine is ready so I can close it down and take a snapshot. Disabling the Database on the FMW Machine I set up the database to start automatically by creating a service called “dbora”.  On the FMW machine I do not need the database running so I can prevent it auto-starting by running the following command: chkconfig –del dbora Note that because I am using a snapshot it is not a waste of disk space to have the DB installed but not used.  As long as I don’t run it, it won’t cost me anything. I can now close the FMW machine down and take a snapshot. Creating a New Domain The FMW machine is now ready to create a new domain.  When creating the domain I can point it at the second machine which is running the database.  I can potentially run these machines on two separate physical machines as long as I have the original virtual machine available to both of the physical machines. Gotchas in Snapshotting VirtualBox does not support the concept of linked machines in a network like some virtualization technologies so when creating a snapshot it is a good idea to shut both VMs down and then take a snapshot on both of them.  This is because we want to keep the database in sync with the middleware.  One way to make sure that this happens would be to place all the domain configuration files on the database server via an NFS share, this would mean that all we would need to snapshot would be the database machine because that would hold all the state and configuration. The Sky’s the Limit We have covered a simple case of having just two machines.  I have a more complicated configuration in which two machine run a RAC database off the same base OS image, and two more machines run a SOA cluster based on the same OS image.  Just remember what machine holds state and what are the consequences of taking a snapshot.

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• How to Create Quality Photo Prints With Free Software

  - by Eric Z Goodnight

  Photoshop may be the professional standard for high quality photo prints, but that doesn’t mean you have to pay hundreds of dollars for printing software. Freeware program Google Picasa can create excellent quality photo prints that’ll only cost you a download. Picasa and other freeware graphics programs are hardly news to savvy geeks, although with a little patience, they can produce quality prints few could tell apart from thousand dollar graphics suites. Stay tuned for links to various graphics programs, and a simple how-to on getting the perfect print settings for your photos Latest Features How-To Geek ETC The Complete List of iPad Tips, Tricks, and Tutorials The 50 Best Registry Hacks that Make Windows Better The How-To Geek Holiday Gift Guide (Geeky Stuff We Like) LCD? LED? Plasma? The How-To Geek Guide to HDTV Technology The How-To Geek Guide to Learning Photoshop, Part 8: Filters Improve Digital Photography by Calibrating Your Monitor Deathwing the Destroyer – WoW Cataclysm Dragon Wallpaper Drag2Up Lets You Drag and Drop Files to the Web With Ease The Spam Police Parts 1 and 2 – Goodbye Spammers [Videos] Snow Angels Theme for Windows 7 Exploring the Jungle Ruins Wallpaper Protect Your Privacy When Browsing with Chrome and Iron Browser

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• Twitter status id conundrum

  - by jamiet

  I have an interest, a slightly perverse one some might say, in using online services and trying to figure out what the underlying (logical) data model is and in this day and age Twitter is one that lends itself very well to scrutiny. Consider this recent tweet of mine: The URL that enables you to see that tweet is http://twitter.com/jamiet/status/12154647354. We can interpret that URL to mean "a tweet by jamiet with an id of 12154647354" and hence we might further assume that the unique identifier for the tweet is {jamiet,12154647354}. However, its well-known that Twitter gives each status a unique ID regardless of who tweeted it so we might expect we could reach that tweet just by using a URL of http://twitter.com/status/12154647354 however (at the time of writing) that only redirects to Twitter's homepage. That seems strange to me especially given that we can use Twitter's API to access information about that tweet using only the id of the status. Witness http://api.twitter.com/1/statuses/show/12154647354.xml: [We can also access a JSON version of that information using http://api.twitter.com/1/statuses/show/12154647354.json] I'm puzzled as to why a tweet can't be accessed using on the main twitter website using the id alone. Anyone have any suggestions? @jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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