Search Results

Search found 13867 results on 555 pages for 'avoid learning'.

Page 459/555 | < Previous Page | 455 456 457 458 459 460 461 462 463 464 465 466  | Next Page >

• using text and ntext SQL Datatypes in RPG

  - by David Stratton

  I'll preface this with saying that I'm a .NET developer, and am NOT an RPG developer. I'm working with one of our RPG developers to come up with a solution, so any suggestions you provide will get passed to him. We have a scenario where we want our iSeries to read from a SQL Server database. One of the columns is a TEXT column. IN RPG, there is no equivalent data type to use for this. We've gone back and forth on this, and our current plan is to change course, and have our SQL Server write out a text file, which the iSeries can pick up and parse. This is, however, a last resort option, as the data in the file is sensitive, and we'd like to avoid the additional security overhead. We've already got the SQL Server locked down as tight as possible (one user only has read access to this, and that user is an iSeries user.) We don't want to have to worry about transferring files back and forth. However, at this point, we see no other option. We have no in-house Java developers, and need to do this in RPG. So I'm wondering if there are any RPG developers out there who have faced this situation and have any advice.

  Read the article

• C# average function without overflow exception

  - by Ron Klein

  .NET Framework 3.5. I'm trying to calculate the average of some pretty large numbers. For instance: using System; using System.Linq; class Program { static void Main(string[] args) { var items = new long[] { long.MaxValue - 100, long.MaxValue - 200, long.MaxValue - 300 }; try { var avg = items.Average(); Console.WriteLine(avg); } catch (OverflowException ex) { Console.WriteLine("can't calculate that!"); } Console.ReadLine(); } } Obviously, the mathematical result is 9223372036854775607 (long.MaxValue - 200), but I get an exception there. This is because the implementation (on my machine) to the Average extension method, as inspected by .NET Reflector is: public static double Average(this IEnumerable<long> source) { if (source == null) { throw Error.ArgumentNull("source"); } long num = 0L; long num2 = 0L; foreach (long num3 in source) { num += num3; num2 += 1L; } if (num2 <= 0L) { throw Error.NoElements(); } return (((double) num) / ((double) num2)); } I know I can use a BigInt library (yes, I know that it is included in .NET Framework 4.0, but I'm tied to 3.5). But I still wonder if there's a pretty straight forward implementation of calculating the average of integers without an external library. Do you happen to know about such implementation? Thanks!! UPDATE: The previous example, of three large integers, was just an example to illustrate the overflow issue. The question is about calculating an average of any set of numbers which might sum to a large number that exceeds the type's max value. Sorry about this confusion. I also changed the question's title to avoid additional confusion. Thanks all!!

  Read the article

• The Date type and the Android database

  - by cdonner

  I understand that SQLite stores dates as long integers. When I read rows into a cursor using the standard method (i.e. using the query() method that reads data into a cursor), the result is a date string that includes the time. If I want a different format, I have to parse the string back into a date - possible, but a bit backwards. By using a ViewBinder (as suggested in this question), I can pretty much do anything I want, but the date is already a string at the time the method executes. The accepted answer to the above question also suggests that storing dates as longs would help avoid this problem. I don't want to do that, just in case I want to interpret my data with something else than this application. Maybe I want to expose it via a provider. Is there a way to handle this in the database adapter instead, i.e. controlling the date format that the cursor contains, so that I don't have to change the schema, and don't have to parse the default output back into a Date type?

  Read the article

• .NET assembly cache / ngen / jit image warm-up and cool-down behavior

  - by Mike Jiang

  Hi, I have an Input Method (IME) program built with C#.NET 2.0 DLL through C++/CLI. Since an IME is always attaching to another application, the C#.NET DLL seems not able to avoid image address rebasing. Although I have applied ngen to create a native image of that C#.NET 2.0 DLL and installed it into Global Assembly Cache, it didn't improved much, approximately 12 sec. down to 9 sec. on a slow PIII level PC. Therefore I uses a small application, which loads all the components referenced by the C#.NET DLL at the boot up time, to "warm up" the native image of that DLL. It works fine to speed up the loading time to 0.5 sec. However, it only worked for a while. About 30 min. later, it seems to "cool down" again. Is there any way to control the behavior of GAC or native image to be always "hot"? Is this exactly a image address rebasing problem? Thank you for your precious time. Sincerely, Mike

  Read the article

• UINavigationController crash because of pushing and poping UIViewControllers

  - by Wayne Lo

  My question is related to my discovery of a reason for UINavigationController to crash. So I will tell you about the discovery first. Please bare with me. The issue: I have a UINavigationController as as subview of UIWindow, a rootViewController class and a custom MyViewController class. The following steps will get a Exc_Bad_Access, 100% reproducible.: [myNaviationController pushViewController:myViewController_1stInstance animated:YES]; [myNaviationController pushViewController:myViewController_2ndInstance animated:YES]; Hit the left back tapBarItem twice (pop out two of the myViewController instances) to show the rootViewController. After a painful 1/2 day of try and error, I finally figure out the answer but also raise a question. The Solutio: I declared many objects in the .m file as a lazy way of declaring private variables to avoid cluttering the .h file. For instance, #impoart "MyViewController.h" NSMutableString*variable1; @implement ... -(id)init { ... varialbe1=[[NSMutableString alloc] init]; ... } -(void)dealloc { [variable1 release]; } For some reasons, the iphone OS may loose track of these "lazy private" variables memory allocation when myViewController_1stInstance's view is unloaded (but still in the navigation controller's stacks) after loading the view of myViewController_2ndInstance. The first time to tap the back tapBarItem is ok since myViewController_2ndInstance'view is still loaded. But the 2nd tap on the back tapBarItem gave me hell because it tried to dealloc the 2nd instance. Executing [variable release] resulted in Exc_Bad_Access because it pointed randomly (loose pointer). To fix this problem is simple, declare variable1 as a @private in the .h file. Here is my Question: I have been using the "lazy private" variables for quite some time without any issues until they are involved in UINavigationController. Is this a bug in iPhone OS? Or there is a fundamental misunderstanding on my part about Objective C? Please help.

  Read the article

• jquery validate: focusCleanup: true and focusInvalid: false don't work as expected

  - by laramichaels

  I am using Joern's jquery validation plugin 1.6. My goal is to have the following behavior: remove the error message for an element once the user focuses it. From what I understand setting 'focusCleanup: true' should take care of this. However (at least on my browser (Firefox 3.5.7 on Linux)), I only get the desired behavior (ie, error message for a field disappearing once you focus it) if I click into the field; it doesn't handle tabbing into the field correctly. Sample code: HTML: <form id='abc' name='abc'> <input type="text" id="t1" name="t1"/> <input type="text" id="t2" name="t2"/> <input type="submit" id="submit" value='submit'/> </form> JS: $("#abc").validate({ focusCleanup: true, focusInvalid: false, rules: {t1: {required: true, email:true}, t2: {required: true,email:true}} }); I am setting 'focusInvalid: false' because the docs say one should avoid combining focusCleanup and focusInvalid; in my experience commenting out that line makes no difference. Am I doing something wrong?

  Read the article

• what can be causes of http server crash?

  - by mithunmo

  Hello , I am using WAMP server on Windows XP. - Apache 2.2.11 - MySQL 5.1.36 (INNODB engine) - PHP 5.3.0 I observe that my WAMP server crashes in the following scenarios 1) IF I use a Low end PC ( low processor speed and low RAM) 2) After making some changes to httpd.conf file .For eg changing the Allow from IP address . But here it crashes only once and then it starts to work fine. 3) Random crashes CRASH LOG szAppName : httpd.exe szAppVer : 2.2.11.0 szModName : php5ts.dll szModVer : 5.3.0.0 offset : 0000c309 C:\DOCUME~1\blrcom\LOCALS~1\Temp\WERc677.dir00\httpd.exe.mdmp C:\DOCUME~1\blrcom\LOCALS~1\Temp\WERc677.dir00\appcompat.txt My questions 1) Does high CPU utilization/LOW RAM can also cause the HTTP server to crash ? 2) excessive file reading as in every 10 seconds ? 3) unlimited script execution time . I have set the maximum execution time in php script to 0 as my script has to execute for sometimes 2-3 days. Is there any way to avoid this ? 4) Access to Database ? Should we use lock before reading and writing Can these be the reasons for random wamp server crashes ? OR is is some other programming error ? Please guide me . Regards, Mithun

  Read the article

• C++ thread safety - exchange data between worker and controller

  - by peterchen

  I still feel a bit unsafe about the topic and hope you folks can help me - For passing data (configuration or results) between a worker thread polling something and a controlling thread interested in the most recent data, I've ended up using more or less the following pattern repeatedly: Mutex m; tData * stage; // temporary, accessed concurrently // send data, gives up ownership, receives old stage if any tData * Send(tData * newData) { ScopedLock lock(m); swap(newData, stage); return newData; } // receiving thread fetches latest data here tData * Fetch(tData * prev) { ScopedLock lock(m); if (stage != 0) { // ... release prev prev = stage; stage = 0; } return prev; // now current } Note: This is not supposed to be a full producer-consumer queue, only the msot recent data is relevant. Also, I've skimmed ressource management somewhat here. When necessary I'm using two such stages: one to send config changes to the worker, and for sending back results. Now, my questions assuming that ScopedLock implements a full memory barrier: do stage and/or workerData need to be volatile? is volatile necessary for tData members? can I use smart pointers instead of the raw pointers - say boost::shared_ptr? Anything else that can go wrong? I am basically trying to avoid "volatile infection" spreading into tData, and minimize lock contention (a lock free implementation seems possible, too). However, I'm not sure if this is the easiest solution. ScopedLock acts as a full memory barrier. Since all this is more or less platform dependent, let's say Visual C++ x86 or x64, though differences/notes for other platforms are welcome, too. (a prelimenary "thanks but" for recommending libraries such as Intel TBB - I am trying to understand the platform issues here)

  Read the article

• Maintaining ISAPI Rewrite Path with the ASP.NET tilde (~)

  - by Adam

  My team is upgrading from ASP.NET 3.5 to ASP.NET 4.0. We are currently using Helicon ISAPI Rewrite to map http://localhost/<account-name>/default.aspx to http://localhost/<virtual-directory>/default.aspx?AccountName=<account-name> where <account-name> is a query string variable and <virtual-directory> is a virtual directory (naturally). Before the upgrade the tilde (~) resolved to http://localhost/<account-name>/... (which I want it to do) and after the upgrade the tilde resolves to http://localhost/<virtual-directory>/... which results in an error because the <account-name> query string is required. I'd like to avoid going down the road of replacing everything with relative paths because there are several features in our system that use the entire URL instead of just the relative path. For what it's worth I'm using IIS7 in Windows 7, Visual Studio 2010 with ASP.NET 4.0 and the 64 bit Helicon ISAPI Rewrite. If I switch back to the ASP.NET 3.5 version then it still works fine (leading me to believe nothing changed in IIS unless it's within the 4.0 app pool - when I switch back and forth between 3.5 and 4.0 I have to change the app pool in IIS). Any ideas? Thanks in advance!

  Read the article

• iPhone: Override UIButton buttonWithType to return subclass

  - by Amagrammer

  I want to be able to create a UIButton with an oversized responsive area. I know that one way to do that is to override the hitTest method in a subclass, but how do I instantiate my custom button object in the first place? [OversizedButton buttonWithType: UIButtonTypeDetailDisclosure]; doesn't work out of the box because buttonWithType returns a UIButton, not an OversizedButton. So it seems like I need to override the buttonWithType method as well. Does anyone know how to do this? @implementation OversizedButton + (id)buttonWithType:(UIButtonType)buttonType { // Construct and return an OversizedButton rather than a UIButton // Needs to handle special types such as UIButtonTypeDetailDisclosure // I NEED TO KNOW HOW TO DO THIS PART } - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event { // Return results if touch event was in oversized region // I ALREADY KNOW HOW TO DO THIS PART } @end Alternatively, maybe I could create the button using alloc/initWithFrame. But the buttonType property is readonly, so how do you create the custom button types? Note: I know there are other ways to do this, such as having an invisible button behind the visible one. I don't care for that approach and would prefer to avoid it. Any help on the approach described above would be very helpful. Thanks

  Read the article

• Problem with TextViews running into each other in RelativeLayout

  - by Janusz

  I have a problem with two Textviews on the same height in a RelativeLayout running into each other. I use the following Layout. <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent"> <ImageView android:id="@+id/logo" android:layout_width="wrap_content" android:layout_height="wrap_content" android:adjustViewBounds="true" android:scaleType="centerInside" android:src="@drawable/icon" /> <TextView android:id="@+id/name" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="NameNameNameNameNameNameName" android:layout_alignParentTop="true" android:layout_toRightOf="@id/logo" android:gravity="clip_horizontal" android:lines="1" /> <TextView android:id="@+id/information" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="information" android:layout_alignParentRight="true" android:layout_alignParentTop="true" /> <TextView android:id="@+id/nrcoupons" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Number" android:layout_alignRight="@id/information" android:layout_alignBottom="@id/logo" /> <TextView android:id="@+id/subcategory" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Subcategory" android:layout_alignLeft="@id/name" android:layout_alignBottom="@id/logo" /> </RelativeLayout> This gives me this view: Everything is as I need it except the two textviews name and information are displayed on the same screen space with the one on top of the other. How can I avoid this?

  Read the article

• How do you keep your business rules DRY?

  - by Mario

  I periodically ponder how to best design an application whose every business rule exists in just a single location. (While I know there is no proverbial “best way” and that designs are situational, people must have a leaning toward one practice or another.) I work for a shop where they prefer to house as much of the business rules as possible in the database. This requires developers in many cases to perform identical front-end validations to avoid sending data to the database that will result in an exception—not very DRY. It grates me anytime I find myself duplicating any kind of logic—even lowly validation logic. I am a single-point-of-truth purist to an anal degree. On the other end of the spectrum, I know of shops that create dumb databases (the Rails community leans in this direction) and handle all of the business logic in a separate tier (in Rails the models would house “most” of this). Note the word “most” which implies that some business logic does end up spilling into other places (in Rails it might spill over into the controllers). In way, a clean separation of concerns where all business logic exists in a single core location is a Utopian fantasy that’s hard to uphold (n-tiered architecture or not). Furthermore, is see the “Database as a fortress” and would agree that it should be built on constraints that cause it to reject bad data. As such, I hold principles that cause a degree of angst as I attempt to balance them. How do you balance the database-as-a-fortress view with the desire to have a single-point-of-truth?

  Read the article

• Algorithm for converting hierarchical flat data (w/ ParentID) into sorted flat list w/ indentation l

  - by eagle

  I have the following structure: MyClass { guid ID guid ParentID string Name } I'd like to create an array which contains the elements in the order they should be displayed in a hierarchy (e.g. according to their "left" values), as well as a hash which maps the guid to the indentation level. For example: ID Name ParentID ------------------------ 1 Cats 2 2 Animal NULL 3 Tiger 1 4 Book NULL 5 Airplane NULL This would essentially produce the following objects: // Array is an array of all the elements sorted by the way you would see them in a fully expanded tree Array[0] = "Airplane" Array[1] = "Animal" Array[2] = "Cats" Array[3] = "Tiger" Array[4] = "Book" // IndentationLevel is a hash of GUIDs to IndentationLevels. IndentationLevel["1"] = 1 IndentationLevel["2"] = 0 IndentationLevel["3"] = 2 IndentationLevel["4"] = 0 IndentationLevel["5"] = 0 For clarity, this is what the hierarchy looks like: Airplane Animal Cats Tiger Book I'd like to iterate through the items the least amount of times possible. I also don't want to create a hierarchical data structure. I'd prefer to use arrays, hashes, stacks, or queues. The two objectives are: Store a hash of the ID to the indentation level. Sort the list that holds all the objects according to their left values. When I get the list of elements, they are in no particular order. Siblings should be ordered by their Name property. Update: This may seem like I haven't tried coming up with a solution myself and simply want others to do the work for me. However, I have tried coming up with three different solutions, and I've gotten stuck on each. One reason might be that I've tried to avoid recursion (maybe wrongly so). I'm not posting the partial solutions I have so far since they are incorrect and may badly influence the solutions of others.

  Read the article

• Working with a large data object between ruby processes

  - by Gdeglin

  I have a Ruby hash that reaches approximately 10 megabytes if written to a file using Marshal.dump. After gzip compression it is approximately 500 kilobytes. Iterating through and altering this hash is very fast in ruby (fractions of a millisecond). Even copying it is extremely fast. The problem is that I need to share the data in this hash between Ruby on Rails processes. In order to do this using the Rails cache (file_store or memcached) I need to Marshal.dump the file first, however this incurs a 1000 millisecond delay when serializing the file and a 400 millisecond delay when serializing it. Ideally I would want to be able to save and load this hash from each process in under 100 milliseconds. One idea is to spawn a new Ruby process to hold this hash that provides an API to the other processes to modify or process the data within it, but I want to avoid doing this unless I'm certain that there are no other ways to share this object quickly. Is there a way I can more directly share this hash between processes without needing to serialize or deserialize it? Here is the code I'm using to generate a hash similar to the one I'm working with: @a = [] 0.upto(500) do |r| @a[r] = [] 0.upto(10_000) do |c| if rand(10) == 0 @a[r][c] = 1 # 10% chance of being 1 else @a[r][c] = 0 end end end @c = Marshal.dump(@a) # 1000 milliseconds Marshal.load(@c) # 400 milliseconds Update: Since my original question did not receive many responses, I'm assuming there's no solution as easy as I would have hoped. Presently I'm considering two options: Create a Sinatra application to store this hash with an API to modify/access it. Create a C application to do the same as #1, but a lot faster. The scope of my problem has increased such that the hash may be larger than my original example. So #2 may be necessary. But I have no idea where to start in terms of writing a C application that exposes an appropriate API. A good walkthrough through how best to implement #1 or #2 may receive best answer credit.

  Read the article

• Is there a way to receive receive data as unsugned char over UDP on QT

  - by user269037

  I need to send floating point numbers using UDP connection to a QT application. Now in QT the only function available is qint64 readDatagram ( char * data, qint64 maxSize, QHostAddress * address = 0, quint16 * port = 0 ) which accepts data in the form of signed character buffer. I can convert my float into a string and send it but it will obviously not be very efficient converting a 4 byte float into a much longer sized character buffer. I got hold of these 2 functions to convert a 4 byte float into an unsinged 32 bit integer to transfer over network which works fine for a simple c++ udp program but for QT I need to receive the data as unsigned char. Is it possible to avoid converting the floatinf point data into a string and then sending it ?? uint32_t htonf(float f) { uint32_t p; uint32_t sign; if (f < 0) { sign = 1; f = -f; } else { sign = 0; } p = ((((uint32_t)f)&0x7fff)<<16) | (sign<<31); // whole part and sign p |= (uint32_t)(((f - (int)f) * 65536.0f))&0xffff; // fraction return p; } float ntohf(uint32_t p) { float f = ((p16)&0x7fff); // whole part f += (p&0xffff) / 65536.0f; // fraction if (((p>>31)&0x1) == 0x1) { f = -f; } // sign bit set return f; }

  Read the article

• Determine whether .NET assemblies were built from the same source

  - by Clayton

  Does anyone know of a way to compare two .NET assemblies to determine whether they were built from the "same" source files? I am aware that there are some differencing utilities available, such as the plugin for Reflector, but I am not interested in viewing differences in a GUI, I just want an automated way to compare a collection of binaries to see whether they were built from the same (or equivalent) source files. I understand that multiple different source files could produce the same IL, and realise that the process would only be sensitive to differences in the IL, not the original source. The main obstacle to just comparing the byte streams for the two assemblies is that .NET includes a field called "MVID" (Module Version Identifier) the assembly. This appears to have a different value for every compilation, so if you build the same code twice the assembly will be different. A related question is, does anyone know how to force the MVID to be the same for each compilation? This would avoid us needing to have a comparison process that is insensitive to differences in the value of the MVID. A consistent MVID would be preferable, as this means that standard checksums could be used. The background behind this is that a third-party company is responsible for independently reviewing and signing off our releases, prior to us being permitted to release to Production. This includes reviewing the source code. They want to independently confirm that the source code we give them matches the binaries that we earlier built, tested and currently plan to deploy. We are looking for a process that allows them to independently build the system from the source we supply them with, and the compare the checksums against the checksums for the binaries we have tested. thanks

  Read the article

• Finding JNP port in JBoss from Servlet

  - by Steve Jackson

  I have a servlet running in JBoss (4.2.2.GA and 4.3-eap) that needs to connect to an EJB to do work. In general this code works fine to get the Context to connect and make RMI calls (all in the same server). public class ContextFactory { public static final int DEFAULT_JNDI_PORT = 1099; public static final String DEFAULT_CONTEXT_FACTORY_CLASS = "org.jnp.interfaces.NamingContextFactory"; public static final String DEFAULT_URL_PREFIXES = "org.jboss.naming:org.jnp.interfaces"; public Context createContext(String serverAddress) { //combine provider name and port String providerUrl = serverAddress + ":" + DEFAULT_JNDI_PORT; //Set properties needed for Context: factory, provider, and package prefixes. Hashtable<String, String> env = new Hashtable<String, String>(3); env.put(Context.INITIAL_CONTEXT_FACTORY, DEFAULT_CONTEXT_FACTORY_CLASS); env.put(Context.PROVIDER_URL, providerUrl); env.put(Context.URL_PKG_PREFIXES, DEFAULT_URL_PREFIXES); return new InitialContext(env); } Now, when I change the JNDI bind port from 1099 in server/conf/jboss-service.xml I can't figure out how to programatically find the correct port for the providerUrl above. I've dumped System.getProperties() and System.getEnv() and it doesn't appear there. I'm pretty sure I can set it in server/conf/jndi.properties as well, but I was hoping to avoid another magic config file. I've tried the HttpNamingContextFactory but that fails "java.net.ProtocolException: Server redirected too many times (20)" env.put(Context.INITIAL_CONTEXT_FACTORY, "org.jboss.naming.HttpNamingContextFactory"); env.put(Context.PROVIDER_URL, "http://" + serverAddress + ":8080/invoker/JNDIFactory"); Any ideas?

  Read the article

• Cocoa threading question.

  - by Steve918

  I would like to implement an observer pattern in Objective-C where the observer implements an interface similar to SKPaymentTransactionObserver and the observable class just extends my base observable. My observable class looks something like what is below. Notice I'm making copies of the observers before enumeration to avoid throwing an exception . I've tried adding an NSLock around add observers and notify observers, but I run into a deadlock. What would be the proper way to handle concurrency when observers are being added as notifications are being sent? @implementation Observable -(void)notifyObservers:(SEL)selector { @synchronized(self) { NSSet* observer_copy = [observers copy]; for (id observer in observer_copy) { if([observer respondsToSelector: selector]) { [observer performSelector: selector]; } } [observer_copy release]; } } -(void)notifyObservers:(SEL)selector withObject:(id)arg1 withObject:(id)arg2 { @synchronized(self) { NSSet* observer_copy = [observers copy]; for (id observer in observer_copy) { if([observer respondsToSelector: selector]) { [observer performSelector: selector withObject: arg1 withObject: arg2]; } } [observer_copy release]; } } -(void)addObserver:(id)observer { @synchronized(self) { [observers addObject: observer]; } } -(void)removeObserver:(id)observer { @synchronized(self) { [observers removeObject: observer]; } }

  Read the article

• How do I keep Visual Studio's Windows Forms Designer from deleting controls?

  - by Sören Kuklau

  With several forms of mine, I occasionally run into the following issue: I edit the form using the designer (Visual Studio 2008, Windows Forms, .NET 2.0, VB.NET) to add components, only to find out later that some minor adjustments were made (e.g. the form's size is suddenly changed by a few pixels), and controls get deleted. This happens silently — event-handling methods automatically have their Handles suffix removed, too, so they never get called, and there's no compiler error. I only notice much later or not at all, because I'm working on a different area in the form. As an example, I have a form with a SplitContainer containing an Infragistics UltraListView to the left, and an UltraTabControl to the right. I added a new tab, and controls within, and they worked fine. I later on found out that the list view's scrollbar was suddenly invisible, due to its size being off, and at least one control was removed from a different tab that I hadn't been working on. Is this a known issue with the WinForms Designer, or with Infragistics? I use version control, of course, so I can compare the changes and merge the deleted code back in, but it's a tedious process that shouldn't be necessary. Are there ways to avoid this? Is there a good reason for this to occur? One clue is that the control that was removed may have code (such as a Load event handler) that expects to be run in run time, not design time, and may be throwing an exception. Could this cause Visual Studio to remove the control?

  Read the article

• FxCop hates my usage of MVVM

  - by Dave

  I've just started to work with FxCop to see how poorly my code does against its full set of rules. I'm starting off with the "Breaking" rules, and the first one I came across was CA2227, which basically says that you should make a collection property's setter readonly, so that you can't accidentally change the collection data. Since I'm using MVVM, I've found it very convenient to use an ObservableCollection with get/set properties because it makes my GUI updates easy and concise in the code-behind. However, I can also see what FxCop is complaining about. Another situation that I just ran into is with WF, where I need to set the parameters when creating the workflow, and I'd hate to have to write a wrapper class around the collection I'm using just to avoid this particular error message. For example, here's a sample runtime error message that I get when I make properties readonly: The activity 'MyWorkflow' has no public writable property named 'MyCollectionOfStuff' What are you opinions on this? I could either ignore this particular error, but that's probably not good because I could conceivably violate this rule elsewhere in the code where MVVM doesn't apply (model only code, for example). I think I could also change it from a property to a class with methods to manipulate the underlying collection, and then raise the necessary notification from the setter method. I'm a little confused... can anyone shed some light on this?

  Read the article

• Implementation review for a MVC.NET app with custom membership

  - by mrjoltcola

  I'd like to hear if anyone sees any problems with how I implemented the security in this Oracle based MVC.NET app, either security issues, concurrency issues or scalability issues. First, I implemented a CustomOracleMembershipProvider to handle the database interface to the membership store. I implemented a custom Principal named User which implements IPrincipal, and it has a hashtable of Roles. I also created a separate class named AuthCache which has a simple cache for User objects. Its purpose is simple to avoid return trips to the database, while decoupling the caching from either the web layer or the data layer. (So I can share the cache between MVC.NET, WCF, etc.) The MVC.NET stock MembershipService uses the CustomOracleMembershipProvider (configured in web.config), and both MembershipService and FormsService share access to the singleton AuthCache. My AccountController.LogOn() method: 1) Validates the user via the MembershipService.Validate() method, also loads the roles into the User.Roles container and then caches the User in AuthCache. 2) Signs the user into the Web context via FormsService.SignIn() which accesses the AuthCache (not the database) to get the User, sets HttpContext.Current.User to the cached User Principal. In global.asax.cs, Application_AuthenticateRequest() is implemented. It decrypts the FormsAuthenticationTicket, accesses the AuthCache by the ticket.Name (Username) and sets the Principal by setting Context.User = user from the AuthCache. So in short, all these classes share the AuthCache, and I have, for thread synchronization, a lock() in the cache store method. No lock in the read method. The custom membership provider doesn't know about the cache, the MembershipService doesn't know about any HttpContext (so could be used outside of a web app), and the FormsService doesn't use any custom methods besides accessing the AuthCache to set the Context.User for the initial login, so it isn't dependent on a specific membership provider. The main thing I see now is that the AuthCache will be sharing a User object if a user logs in from multiple sessions. So I may have to change the key from just UserId to something else (maybe using something in the FormsAuthenticationTicket for the key?).

  Read the article

• Update multiple rows with known keys without inserting new rows if nonexistent keys are found

  - by Kirzilla

  Hello, Let's imagine that we have table items... table: items item_id INT PRIMARY AUTO_INCREMENT title VARCHAR(255) views INT Let's imagine that it is filled with something like (1, item-1, 10), (2, item-2, 10), (3, item-3, 15) I want to make multi update view for this items from data taken from this array [item_id] = [views] '1' => '50', '2' => '60', '3' => '70', '5' => '10' IMPORTANT! Please note that we have item_id=5 in array, but we don't have item_id=5 in database. I can use INSERT ... ON DUPLICATE KEY UPDATE, but this way image_id=5 will be inserted into talbe items. How to avoid inserting new key? I just want item_id=5 be skipped because it is not in table. Of course, before execution I can select existing keys from items table; then compare with keys in array; delete nonexistent keys and perform INSERT ... ON DUPLICATE KEY UPDATE. But maybe there is some more elegant solutions? Thank you.

  Read the article

• COM Object Clean Up

  - by Reggie McCray

  What is the difference between the two lines of code below: CComPtr< IInterface > m_interface; IInterface* m_interface; I know that CComPtr help eliminate memory leaks, but I am getting inconsistent results. When declaring the pointer with CComPtr< IInterface > m_interface; and using the interface in my C# code there are no errors, however using the Interface in VC++ I get an unhandled exception error, even if I comment out the instance creation of IInterface. I am pretty sure the problem is in here somewhere: STDMETHODIMP CSomeClass::get_IClass(IClass** var) { return m_class_var->QueryInterface(var); } STDMETHODIMP CSomeClass::putref_IClass(IClass* var) { m_class_var = var; return S_OK; } When I declare the interface pointer with: IInterface* m_interface; I get a RPC_E_SERVERFAULT error when testing the Interface in C# and have to explicitly call GC.Collect() to avoid the error being thrown after instantiation of a few objects. When testing the Interface in VC++ the error is consistent however when it occurs is different. If I comment out the instance creation of IInterface the code runs fine, however when I try to create an instance I get same error as before, just a vague unhandled exception error. What am I doing wrong here?

  Read the article

• How to secure Add child record functionality in MVC on Parent's view?

  - by RSolberg

  I'm trying to avoid some potential security issues as I expose some a new set of functionality into the real world. This is basically functionality that will allow for a new comment to be added via a partialview on the "Parent" page. My comment needs to know a couple of things, first what record is the comment for and secondly who is making the comment. I really don't like using a hidden field to store the ID for the Parent record in the add comment form as that can be easily changed with some DOM mods. How should I handle this? PARENT <% Html.RenderPartial("AddComment", Model.Comments); %> CHILD <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<CommentsViewModel>" %> <% using (Html.BeginForm("AddComment", "Requests")) {%> <fieldset> <legend>New Comment</legend> <%= Html.HiddenFor(p => p.RequestID) %> <%= Html.TextBoxFor(p => p.Text) %> &nbsp; <input type="submit" value="Add" /> </fieldset> <% } %> CONTROLLER [AcceptVerbs(HttpVerbs.Post)] public void AddComment(CommentsViewModel commentsModel) { var user = GetCurrentUser(); commentsModel.CreatedByID = user.UserID; RequestsService.AddComment(commentsModel); }

  Read the article

• 8 bit enum, in C

  - by oxinabox.ucc.asn.au

  I have to store instuctions, commands that I will be receiving via serial. The commands will be 8 bits long. I'd like to use Enumerations to deal with them in my code. Only a enumeration corresponds to a ... on this platform I think a 16 bit integer. I need to preserve transparancy between command name, and its value. So as to avoid having to translate an 8-bit number received in serial into any type. BTW the platform is AVR ATmega169V microcontroller, on the Butterfly demo board. It may be being underclocked to preserve power (I'm opposed to this, I believe the ATmega169V uses no power, not next to a router. But that's getting offtopic.) So I need to keep things fast, and I don't have any luxuries like file I/O. Or operating systems. So any suggestions as to what type I should be using to store 8-bit commands? There has got to be something better than a massive header of #defines.

  Read the article

< Previous Page | 455 456 457 458 459 460 461 462 463 464 465 466  | Next Page >