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  • Merging datasets with 2 different time variables in SAS

    - by John
    Hye Guys, for those regularly browsing this site sorry for already another question (however I did solve my last question myself!) I have another problem with merging datasets, it seems that accounting for time in datasets is a real pain in the ass. I succesfully managed to merge on months in my previous datasets, however it seems I have a final dataset which only has quarter as a time count variable. So where all my normal databases have month 1- xxx as an indicator of time, this database had quarter as an indicator of time. I still want to add the variables of this last database, let's call it TVOL, into my WORK database. Quick summary QUARTER: Quarter 0 = JAN1996-MAR1996 Month: Month 0 = JAN1996 Example: TVOL TVOL _ Ticker ____ Quarter 1500 _ AA ________ -1 52546 _ BB ________ 15 Example: WORK BETA _ Ticker ____ Month 1.52 _ AA ________ 2 1.54__ BB _______ 3 Example: Merged: BETA ______ TVOL __ Ticker ____ Month 1.52 _______ 500 ___ AA _______ 2 I now want to merge this 2 tables using following relationship if the month is in quarter 1, the data of quarter 0 has to be used, so if i have an observation i nWORK with date 2FEB1996 the TVOL of quarter -1 has to be put behind this observation. Something like IF month = quarter i use data quarter i-1. Also, as TVOL is measured quarterly and I have to put in monthly I have to take the average, so (TVOL/3) should be added as a variable. Thanks!

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  • Best support now on windows: Mercurial or Git?

    - by mamcx
    I want to change my current subversion setup to Mercurial or Git. I read about the two and I have a conflicted view about how well they work on windows. Alot of pages say Git is sub-par on windows, slow and badly integrated. And almost everyone say Mercurial is better. But some say Git now is better and Mercurial is behind. I check the screenshots of TortoiseHG and TortoiseGIT and the mercurial one look "worse"... but maybe is just crappy screenshots? I read about the two, prefer the command-line interface of Mercurial, but seriously, I don't pretend to touch the command line. And if one of the two is a real improvenment to SVN, I don't have to do that (In SVN is necesary go to the metal because something need fix). In SVN I have issues when commit or get code made on OSX (I code on Windows, OSX, Solaris. Mainly windows). So I hope don't get that issues again (I mean, failure to commit to the repo). I have a small repository, doing solo.

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  • WPF: How to connect to a sql ce 3.5 database with ADO.NET?

    - by EV
    Hi, I'm trying to write an application that has two DataGrids - the first one displays customers and the second one selected customer's records. I have generated the ADO.NET Entity Model and the connection property are set in App.config file. Now I want to populate the datagrids with the data from sql ce 3.5 database which does not support LINQ-TO-SQL. I used this code for the first datagrid in code behind: CompanyDBEntities db; private void Window_Loaded(object sender, RoutedEventArgs e) { db = new CompanyDBEntities(); ObjectQuery<Employees> departmentQuery = db.Employees; try { // lpgrid is the name of the first datagrid this.lpgrid.ItemsSource = departmentQuery; } catch (Exception ex) { MessageBox.Show(ex.Message); } However, the datagrid is empty although there are records in a database. It would also be better to use it in MVVM pattern but I'm not sure how does the ado.net and MVVM work together and if it is even possible to use them like that. Could anyone help? Thanks in advance.

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  • How large a role does subjectiveness play in programming?

    - by Bob
    I often read about the importance of readability and maintainability. Or, I read very strong opinions about which syntax features are bad or good. Or discussions about the values of certain paradigms, like OOP. Aside from that, this same question floats about in my mind whenever I read debates on SO or Meta about subjective questions. Or read questions about best practices and sometimes find myself or others disagreeing. What role does subjectiveness play within the programming realm? Sometimes I think it plays a large role. Software developers are engineers in a way, but also people. A large part of programming is dealing with code that's human readable. This is very different from Math or Physics or other disciplines with very exact and structured rules. Here the exact structure and rules are largely up in the air, changeable on a whim, and hence the amount of languages in existence. And one person may find one language very readable, and another person may find their own language the most comforting. The same with practices. One person may not like certain accepted practices. I myself find splitting classes into different files very unreadable, for instance. But, I can't say rules haven't helped in general. Certain practices have and do make life easier. And new languages have given rise to syntax and structure that make life easier. There's certainly been a progression towards code that is easier to read and maintain even given a largely diverse group of people. So maybe these things aren't as subjective as I thought. It reminds me, in a way, of UI design. Certainly it's subjective, but then there's an entire discipline involved in crafting good UI and it tends to work. Is there something non-subjective about the ideas behind maintainability, readability, and other best practices? Is there something tangible to grasp when one develops a new language or thinks of new practices?

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  • Adding Control to Container Control that is in User Control - How to properly initialize?

    - by DougJones
    Let's say I have a user control MyUserControl, which has a container control (it's a server control, but it could just be a Panel) and a dropdownlist. The dropdownlist is not in the container control initially. In it's code-behind, I am overriding OnInit and creating the user control, which includes populating a dropdownlist and adding that dropdownlist to my container control. I have a public property Year, which is an int. Based on the value of Year, I want to populate the dropdownlist. The problem is that in OnInit, year is always 0. On the page Init, I am setting year, but that doesn't run until AFTER the control's Init runs. If I try to set the value on PreInit on the page, the page hasn't initialized the control and I get invalid null reference when setting a value to the control. My question is: How can I properly initialize the control? How can I set the value on the page, before the control actually gets initialized? If I move the control's code to OnLoad, it'll work until I have to do a postback. In this case I need to, though!

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  • Passing a list of ints to WebMethod using jQuery and ajax.

    - by birdus
    I'm working on a web page (ASP.NET 4.0) and am just starting simple to try and get this ajax call working (I'm an ajax/jQuery neophyte) and I'm getting an error on the call. Here's the js: var TestParams = new Object; TestParams.Items = new Object; TestParams.Items[0] = 1; TestParams.Items[1] = 5; TestParams.Items[2] = 10; var finalObj = JSON.stringify(TestParams); var _url = 'AdvancedSearch.aspx/TestMethod'; $(document).ready(function () { $.ajax({ type: "POST", url: _url, data: finalObj, contentType: "application/json; charset=utf-8", dataType: "json", success: function (msg) { $(".main").html(msg.d); }, error: function (xhr, ajaxOptions, thrownError) { alert(thrownError.toString()); } }); Here's the method in my code behind file: [Serializable] public class TestParams { public List<int> Items { get; set; } } public partial class Search : Page { [WebMethod] public static string TestMethod(TestParams testParams) { // I never hit a breakpoint in here // do some stuff // return some stuff return ""; } } Here's the stringified json I'm sending back: {"Items":{"0":1,"1":5,"2":10}} When I run it, I get this error: Microsoft JScript runtime error: 'undefined' is null or not an object It breaks on the error function. I've also tried this variation on building the json (based on a sample on a website) with this final json: var TestParams = new Object; TestParams.Positions = new Object; TestParams.Positions[0] = 1; TestParams.Positions[1] = 5; TestParams.Positions[2] = 10; var DTO = new Object; DTO.positions = TestParams; var finalObj = JSON.stringify(DTO) {"positions":{"Positions":{"0":1,"1":5,"2":10}}} Same error message. It doesn't seem like it should be hard to send a list of ints from a web page to my webmethod. Any ideas? Thanks, Jay

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  • changing default my.cnf path in mysql

    - by user377941
    I am having two mysql instances on same machine. The installations are on /usr/loca/mysql1 and /usr/local/mysql2. I m having separate my.cnf files located in /etc/mysql1 and /etc/mysql2. I installed the first instance of my sql using source distribution and with the --prefix=/usr/local/mysql1 option. The second one i got from copying and pastinf the same directory to /usr/local/mysql2. When i start the mysql daemon on /usr.local/mysql/libexec it reads the my.cnf file in /etc/mysql1. And if i start the mysql daemon in /usr/local/mysql2 it reads the same my.cnf file. I have separate port numbers and .sock files defined in the .cnf file in those 2 locations. I can read the my.cnf file in the second location by using --defaults-file=/etc/mysql2/my.cnf option on mysqld startup. I dnt need to enter this each and every time i start the daemon. If i am going to have more instances how can i point the correct my.cnf file to read to each and every mysql daemon. What is the retionale behind mysqld links with the my.cnf file. how can i predefine the location of my.cnf file for each instance.

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  • Please help debug this ASP.Net [VB] code. Trying to write to text file from SQL Server DB.

    - by NJTechGuy
    I am a PHP programmer. I have no .Net coding experience (last seen it 4 years ago). Not interested in code-behind model since this is a quick temporary hack. What I am trying to do is generate an output.txt file whenever the user submits new data. So an output.txt file if exists should be replaced with the new one. I want to write data in this format : 123|Java Programmer|2010-01-01|2010-02-03 124|VB Programmer|2010-01-01|2010-02-03 125|.Net Programmer|2010-01-01|2010-02-03 I don't know VB, so not sure about string manipulations. Hope a kind soul can help me with this. I will be grateful to you. Thank you :) <%@ Import Namespace="System.IO" %> <%@ Import Namespace="System.Data" %> <%@ Import Namespace="System.Data.SqlClient" %> <script language="vb" runat="server"> sub Page_Load(sender as Object, e as EventArgs) Dim sqlConn As New SqlConnection("Data Source=winsqlus04.1and1.com;Initial Catalog=db28765269;User Id=dbo2765469;Password=ByhgstfH;") Dim myCommand As SqlCommand Dim dr As SqlDataReader Dim FILENAME as String = Server.MapPath("Output4.txt") Dim objStreamWriter as StreamWriter ' If Len(Dir$(FILENAME)) > 0 Then Kill(FILENAME) objStreamWriter = File.AppendText(FILENAME) Try sqlConn.Open() 'opening the connection myCommand = New SqlCommand("SELECT id, title, CONVERT(varchar(10), expirydate, 120) AS [expirydate],CONVERT(varchar(10), creationdate, 120) AS [createdate] from tblContact where flag = 0 AND ACTIVE = 1", sqlConn) 'executing the command and assigning it to connection dr = myCommand.ExecuteReader() While dr.Read() objStreamWriter.WriteLine("JobID: " & dr(0).ToString()) objStreamWriter.WriteLine("JobID: " & dr(2).ToString()) objStreamWriter.WriteLine("JobID: " & dr(3).ToString()) End While dr.Close() sqlConn.Close() Catch x As Exception End Try objStreamWriter.Close() Dim objStreamReader as StreamReader objStreamReader = File.OpenText(FILENAME) Dim contents as String = objStreamReader.ReadToEnd() lblNicerOutput.Text = contents.Replace(vbCrLf, "<br>") objStreamReader.Close() end sub </script> <asp:label runat="server" id="lblNicerOutput" Font-Name="Verdana" />

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  • How do I get many, but not all, property values from View to Presenter in WebFormsMvp?

    - by andrej351
    Hey there, What is the best way to get a number of property values of a business object from the View to the Presenter in a WebFormsMvp page? Here is what i propose: The scenario is, I have a business object called Quote which i would like to load form the database, edit and then save. The Quote class has heaps of properties on it. The form is concerned with about 20 of these properties. I have existing methods to load/save a Quote object to/from the database. I now need to wire this all together. So, in the View_Load handler on my presenter i intend to do something like this: public void View_Load(object sender, EventArgs e) { View.Model.Quote = quoteService.Read(quoteId); } And then bind all my controls as follows: <asp:TextBox ID="TotalPriceTextBox" runat="server" Text="<%# Model.Quote.TotalPrice %>" /> All good, the data is on the screen. The user then makes a bunch of changes and hits a "Submit" button. Here is where I'm unsure. I create a class called QuoteEventArgs exposing the 20 properties the form is able to edit. When the View raises the Submit button's event, I set these properties to the values of the controls in the code behind. Then raise the event for the presenter to respond to. The presenter re-loads the Quote object from the database, sets all the properties and saves it to the database. Is this the right way to do this? If not, what is? Cheers, Andrej.

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  • How can I validate/secure/authenticate a JavaScript-based POST request?

    - by Bungle
    A product I'm helping to develop will basically work like this: A Web publisher creates a new page on their site that includes a <script> from our server. When a visitor reaches that new page, that <script> gathers the text content of the page and sends it to our server via a POST request (cross-domain, using a <form> inside of an <iframe>). Our server processes the text content and returns a response (via JSONP) that includes an HTML fragment listing links to related content around the Web. This response is cached and served to subsequent visitors until we receive another POST request with text content from the same URL, at which point we regenerate a "fresh" response. These POSTs only happen when our cached TTL expires, at which point the server signifies that and prompts the <script> on the page to gather and POST the text content again. The problem is that this system seems inherently insecure. In theory, anyone could spoof the HTTP POST request (including the referer header, so we couldn't just check for that) that sends a page's content to our server. This could include any text content, which we would then use to generate the related content links for that page. The primary difficulty in making this secure is that our JavaScript is publicly visible. We can't use any kind of private key or other cryptic identifier or pattern because that won't be secret. Ideally, we need a method that somehow verifies that a POST request corresponding to a particular Web page is authentic. We can't just scrape the Web page and compare the content with what's been POSTed, since the purpose of having JavaScript submit the content is that it may be behind a login system. Any ideas? I hope I've explained the problem well enough. Thanks in advance for any suggestions.

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  • howto distinguish composition and self-typing use-cases

    - by ayvango
    Scala has two instruments for expressing object composition: original self-type concept and well known trivial composition. I'm curios what situations I should use which in. There are obvious differences in their applicability. Self-type requires you to use traits. Object composition allows you to change extensions on run-time with var declaration. Leaving technical details behind I can figure two indicators to help with classification of use cases. If some object used as combinator for a complex structure such as tree or just have several similar typed parts (1 car to 4 wheels relation) than it should use composition. There is extreme opposite use case. Lets assume one trait become too big to clearly observe it and it got split. It is quite natural that you should use self-types for this case. That rules are not absolute. You may do extra work to convert code between this techniques. e.g. you may replace 4 wheels composition with self-typing over Product4. You may use Cake[T <: MyType] {part : MyType} instead of Cake { this : MyType => } for cake pattern dependencies. But both cases seem counterintuitive and give you extra work. There are plenty of boundary use cases although. One-to-one relations is very hard to decide with. Is there any simple rule to decide what kind of technique is preferable? self-type makes you classes abstract, composition makes your code verbose. self-type gives your problems with blending namespaces and also gives you extra typing for free (you got not just a cocktail of two elements but gasoline-motor oil cocktail known as a petrol bomb). How can I choose between them? What hints are there? Update: Let us discuss the following example: Adapter pattern. What benefits it has with both selt-typing and composition approaches?

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  • Need help finding a good curriculum/methodology for self-teaching to program from scratch

    - by BrotherGA2
    My friend and I have both dedicated ourselves to learning the essentials of programming by June of this year from nearly no programming experience. I have done some research and have come to the conclusion that using the Python language will be the best for us, but I am open to suggestions with good reasoning behind them. My motives for learning programming are: Potential Career Path to be able to create programs that can: solve problems; entertain, i.e. useful applications and games. Online college lectures + book (which I am willing to purchase) sounds like a good combination, but I do not know which would be most suitable for me. tl;dr: What I would like to find from the excellent people here is the following: a good, potentially best, programming course and/or book that is well structured and uses good pedagogy so that a person dedicated to learn programming may do so by following its curriculum (or use it to develop a curriculum) over the course of a few months. Thanks! (I apologize if this type of question is not considered proper etiquette, but I haven't found a consensus on this, and would like some guidance beyond the research I've already done)

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  • latin1/unicode conversion problem with ajax request and special characters

    - by mfn
    Server is PHP5 and HTML charset is latin1 (iso-8859-1). With regular form POST requests, there's no problem with "special" characters like the em dash (–) for example. Although I don't know for sure, it works. Probably because there exists a representable character for the browser at char code 150 (which is what I see in PHP on the server for a literal em dash with ord). Now our application also provides some kind of preview mechanism via ajax: the text is sent to the server and a complete HTML for a preview is sent back. However, the ordinary char code 150 em dash character when sent via ajax (tested with GET and POST) mutates into something more: %E2%80%93. I see this already in the apache log. According to various sources I found, e.g. http://www.tachyonsoft.com/uc0020.htm , this is the UTF8 byte representation of em dash and my current knowledge is that JavaScript handles everything in Unicode. However within my app, I need everything in latin1. Simply said: just like a regular POST request would have given me that em dash as char code 150, I would need that for the translated UTF8 representation too. That's were I'm failing, because with PHP on the server when I try to decode it with either utf8_decode(...) or iconv('UTF-8', 'iso-8859-1', ...) but in both cases I get a regular ? representing this character (and iconv also throws me a notice: Detected an illegal character in input string ). My goal is to find an automated solution, but maybe I'm trying to be überclever in this case? I've found other people simply doing manual replacing with a predefined input/output set; but that would always give me the feeling I could loose characters. The observant reader will note that I'm behind on understanding the full impact/complexity with things about Unicode and conversion of chars and I definitely prefer to understand the thing as a whole then a simply manual mapping. thanks

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  • Why does a non-dynamically created iframe shim show, but a dynamically created one does not?

    - by Carter
    I have a custom control that is made up of a text field and the ajax control toolkit dateextender. In IE6 I'm hitting the z-index bug where the calendar is showing behind select boxes. If I have the shim sitting in the control, initially hidden, it seems to display fine when the calendar is shown, but when I try to dynamically create the shim on showing it doesn't appear. I've tried bgiframe and some examples I found on SO, no luck. Here is my javascript code currently... var dateEditorShim; function dateEditor_OnShown(dateControl, emptyEventArgs) { var shimWidth = dateControl._width; var shimHeight = dateControl._height; //var dateEditorShim; //dateEditorShim = document.getElementById(dateEditorShimId); dateEditorShim = document.createElement('iframe'); dateEditorShim.setAttribute('src', 'javascript:"";'); dateEditorShim.setAttribute('frameBorder', '0'); dateEditorShim.style.width = dateControl._popupDiv.offsetWidth; dateEditorShim.style.height = dateControl._popupDiv.offsetHeight; dateEditorShim.style.top = dateControl._popupDiv.style.top; dateEditorShim.style.left = dateControl._popupDiv.style.left; dateControl._popupDiv.style.zIndex = 999; dateEditorShim.style.zIndex = 998; dateEditorShim.style.display = "block"; } function dateEditor_OnHiding(dateControl, emptyEventArgs) { var shimWidth = 0; var shimHeight = 0; //var dateEditorShim; //dateEditorShim = document.getElementById(dateEditorShimId); dateEditorShim.style.width = 0; dateEditorShim.style.height = 0; dateEditorShim.style.top = 0; dateEditorShim.style.left = 0; dateEditorShim.style.display = "none"; } You'll notice I have a commented out bit of code that gets an iframe that is embedded into the page, as I said, in this case the iframe at least shows up, but when I dynamically create it like the code above currently, it doesn't. I'm trying to figure out why. Any ideas?

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  • Preventing a button from responding to 'Enter' in ASP.net

    - by kd7iwp
    I have a master template that all the pages on my site use. In the template there is an empty panel. In the code-behind for the page an imagebutton is created in the panel dynamically in my Page_Load section (makes a call to the DB to determine which button should appear via my controller). On some pages that use this template and have forms on them, pressing the Enter key fires the click event on this imagebutton rather than the submit button in the form. Is there a simple way to prevent the imagebutton click event from firing unless it's clicked by the mouse? I'm thinking a javascript method is a hack, especially since the button doesn't even exist in the master template until the button is dynamically created on Page_Load (this is ugly since I can't simply do <% =btnName.ClientId %> to refer to the button's name in my aspx page). I tried setting a super-high tabindex for the image button and that did nothing. Also set the button to be the DefaultButton in its panel on the master template but that did not work either.

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  • Modify request querystring paramaters to build a new link without resorting to string manipulation

    - by Andrew M
    Hi All, I want to dynamically populate a link with the URI of the current request, but set one specific query string parameter. All other querystring paramaters (if there are any) should be left untouched. And I don't know in advance what they might be. Eg, imagine I want to build a link back to the current page, but with the querystring parameter "valueOfInterest" always set to be "wibble" (I'm doing this from the code-behind of an aspx page, .Net 3.5 in C# FWIW). Eg, a request for either of these two: /somepage.aspx /somepage.aspx?valueOfInterest=sausages would become: /somepage.aspx?valueOfInterest=wibble And most importantly (perhaps) a request for: /somepage.aspx?boring=something /somepage.aspx?boring=something&valueOfInterest=sausages would preserve the boring params to become: /somepage.aspx?boring=something&valueOfInterest=wibble Caveats: I'd like to avoid string manipulation if there's something more elegant in asp.net that is more robust. However if there isn't something more elegant, so be it. I've done (a little) homework: I found a blog post which suggested copying the request into a local HttpRequest object, but that still has a read-only collection for the querystring params. I've also had a look at using a URI object, but that doesn't seem to have a querystring

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  • How to choose light version of databse system

    - by adopilot
    I am starting one POS (Point of sale) project. Targeting system is going to be written in C# .NET 2 WinForms and as main database server We are going to use MS-SQL Server. As we have a lot of POS devices in chain for one store I will love to have backend local data base system on each POS device. Scenario are following: When main server goes down!! POS application should continue working "off-line" with local database, until connection to main server come up again. Now I am in dilemma which local database is going to be most adoptable for me. Here is some notes for helping me point me in right direction: To be Light "My POS devices art usually old and suffering with performances" To be Free "I have a lot of devices and I do not wont additional cost beside main SQL serer" One day Ill love to try all that port on Mono and Linux OS. Here is what I've researched so far: Simple XML "Light but I am afraid of performance, My main table of items is average of 10K records" SQL-Expres "I am afraid that my POS devices is poor with hardware for SQLExpres, and also hard to install on each device and configure" Less known Advantage Database Server have free distribution of offline ADT system. DBF with extended Library,"Respect for good old DBFs but that era is behind Me with clipper and DBFs" MS Access Sqlite "Mostly like for now, but I am afraid how it is going to pair with MS SQL do they have same Data taypes". I know that in this SO is a lot of subjective data, but at least can someone recommended some others lite database system, or things that I shod most take attention before I choice database.

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  • Runtime Exception when using Custom Healthmonitoring event in medium trust

    - by Elementenfresser
    Hi, I'm using custom healthmonitoring events in ASP.NET We recently moved to a new server with default High Trust Permissions. Literature says that healthmonitoring and custom events should work under Medium or higher trust (http://msdn.microsoft.com/en-us/library/bb398933.aspx). Problem is it doesn't. In less than high trust I get a SecurityException saying The application attempted to perform an operation not allowed by the security policy It works in Full trust or when I remove the inheritance of System.Web.Management.WebErrorEvent. Any suggestions anyone? Here is the super simple code behind with a custom event defined: public partial class Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { try { CallCustomEvent(); } catch (Exception ex) { Response.Write(ex.Message); throw ex; } } /// <summary> /// this metho is never called due to lacking permissions... /// </summary> private void CallCustomEvent() { try { //do something useful here } catch (Exception) { //code to instantiate the forbidden inheritance... WebBaseEvent.Raise(new CustomEvent()); } } } /// <summary> /// custom error inheriting WebErrorEvent which is not allowed in high trust? can't believe that... /// </summary> public class CustomEvent : WebErrorEvent { public CustomEvent() : base("test", HttpContext.Current.Request, 100001, new ApplicationException("dummy")) { } } and the Web Config excerpt for high trust: <system.web> <trust level="High" originUrl="" />

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  • Help understanding .NET delegates, events, and eventhandlers

    - by Seth Spearman
    Hello, In the last couple of days I asked a couple of questions about delegates HERE and HERE. I confess...I don't really understand delegates. And I REALLY REALLY REALLY want to understand and master them. (I can define them--type safe function pointers--but since I have little experience with C type languages it is not really helpful.) Can anyone recommend some online resource(s) that will explain delegates in a way that presumes nothing? This is one of those moments where I suspect that VB actually handicaps me because it does some wiring for me behind the scenes. The ideal resource would just explain what delegates are, without reference to anything else like (events and eventhandlers), would show me how all everything is wired up, explain (as I just learned) that delegates are types and what makes them unique as a type (perhaps using a little ildasm magic)). That foundation would then expand to explain how delegates are related to events and eventhandlers which would need a pretty good explanation in there own right. Finally this resource could tie it all together using real examples and explain what wiring DOES happen automatically by the compiler, how to use them, etc. And, oh yeah, when you should and should not use delegates, in other words, downsides and alternatives to using delegates. What say ye? Can any of you point me to resource(s) that can help me begin my journey to mastery? EDIT One last thing. The ideal resource will explain how you can and cannot use delegates in an interface declaration. That is something that really tripped me up. Thanks for your help. Seth

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  • FindControl in DataList Edit Mode

    - by Doug
    As a new .net/C# web begginner, I always get tripped up when I try to use FindControl. Blam -flat on my face. Here is my current FindControl problem: I have an .aspx page and Form, then ajax updatePanel, inside it there is my DataList (DataList1) that has an EditItemTemplate: that has the following: <EditItemTemplate> <asp:Label ID="thumbnailUploadLabel" runat="server" text="Upload a new thumbnail image:"/><br /> <asp:FileUpload ID="thumbnailImageUpload" runat="server" /> <asp:Button ID="thunbnailImageUploadButton" runat="server" Text="Upload Now" OnClick="thumbnailUpload"/><br /> </EditItemTemplate> In my C# code behind I have the OnClick code for the fileUpload object: protected void thumbnailUpload(object s, EventArgs e) { if (thumbnailImageUpload.HasFile) { //get name of the file & upload string imageName = thumbnailImageUpload.FileName; thumbnailImageUpload.SaveAs(MapPath("../../images/merch_sm/" + imageName)); //let'em know that it worked (or didn't) thumbnailUploadLabel.Text = "Image " + imageName + "has been uploaded."; } else { thumbnailUploadLabel.Text = "Please choose a thumbnail image to upload."; } So of course I'm getting "Object reference not set to an instance of an object" for the FileUpload and the Label. What is the correct syntax to find these controls, before dealing with them in the OnClick event? The only way Ive used FindControl is something like: label thumbnailUploadLabel = DataList1.FindControl("thumbnailUploadLabel") as Label; But of course this is throwing the "Object reference not set to an instance of an object" error. Any help is very much appreciated. (I've also seen the 'recursive' code out there that is supposed to make using FindControl easier. Ha! I'm so green at C# that I don't even know how to incorporate those into my project.) Thanks to all for taking a look at this.

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  • Why do programmers have to learn for their whole lives and aren't you afraid of that?

    - by serg555
    Programming technologies are evolving so fast that programmers constantly have to learn more and more to catch up whether you want it or not. Often it is not just learning more in the same direction but starting from a scratch. Lets say you were a topnotch programmer in 1999 who quit for 10 years and went to a job interview in 2009 (funny even to imagine) - how much of your knowledge is still needed? And if we take a carpenter, engineer, doctor or even mathematician - they all are still good specialists after 10 years. So why programming is so not stable? Is it because it is just relatively new or because something important is still missing after 50 years and we can't find it to settle in that direction? Do you think after some time situation will change? Learning something new all the time is exciting and all, but it is starting to worry me that as I become older it will be harder and harder. After all "you can't teach an old dog new tricks" and I'm afraid that at the end I just end up behind college students and become one of those "cobol dinosaurs", only it will be probably "java dinosaurs" by that time.

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  • Lightweight alternative to Manual/AutoResetEvent in C#

    - by sweetlilmre
    Hi, I have written what I hope is a lightweight alternative to using the ManualResetEvent and AutoResetEvent classes in C#/.NET. The reasoning behind this was to have Event like functionality without the weight of using a kernel locking object. Although the code seems to work well in both testing and production, getting this kind of thing right for all possibilities can be a fraught undertaking and I would humbly request any constructive comments and or criticism from the StackOverflow crowd on this. Hopefully (after review) this will be useful to others. Usage should be similar to the Manual/AutoResetEvent classes with Notify() used for Set(). Here goes: using System; using System.Threading; public class Signal { private readonly object _lock = new object(); private readonly bool _autoResetSignal; private bool _notified; public Signal() : this(false, false) { } public Signal(bool initialState, bool autoReset) { _autoResetSignal = autoReset; _notified = initialState; } public virtual void Notify() { lock (_lock) { // first time? if (!_notified) { // set the flag _notified = true; // unblock a thread which is waiting on this signal Monitor.Pulse(_lock); } } } public void Wait() { Wait(Timeout.Infinite); } public virtual bool Wait(int milliseconds) { lock (_lock) { bool ret = true; // this check needs to be inside the lock otherwise you can get nailed // with a race condition where the notify thread sets the flag AFTER // the waiting thread has checked it and acquires the lock and does the // pulse before the Monitor.Wait below - when this happens the caller // will wait forever as he "just missed" the only pulse which is ever // going to happen if (!_notified) { ret = Monitor.Wait(_lock, milliseconds); } if (_autoResetSignal) { _notified = false; } return (ret); } } }

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  • Can the Singleton be replaced by Factory?

    - by lostiniceland
    Hello Everyone There are already quite some posts about the Singleton-Pattern around, but I would like to start another one on this topic since I would like to know if the Factory-Pattern would be the right approach to remove this "anti-pattern". In the past I used the singleton quite a lot, also did my fellow collegues since it is so easy to use. For example, the Eclipse IDE or better its workbench-model makes heavy usage of singletons as well. It was due to some posts about E4 (the next big Eclipse version) that made me start to rethink the singleton. The bottom line was that due to this singletons the dependecies in Eclipse 3.x are tightly coupled. Lets assume I want to get rid of all singletons completely and instead use factories. My thoughts were as follows: hide complexity less coupling I have control over how many instances are created (just store the reference I a private field of the factory) mock the factory for testing (with Dependency Injection) when it is behind an interface In some cases the factories can make more than one singleton obsolete (depending on business logic/component composition) Does this make sense? If not, please give good reasons for why you think so. An alternative solution is also appreciated. Thanks Marc

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  • Using C#, can you drag a canvas in WPF?

    - by TERACytE
    Can you drag a canvas in WPF? How do you set the position of the canvas? Here is what I got so far: /// xaml <Window x:Class="TestApp.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Height="350" Width="525" WindowStyle="None" ResizeMode="NoResize" AllowsTransparency="True" Background="Transparent" Loaded="MainWindow_Loaded"> <Canvas Name="ParentCanvas" Background="#FF6E798D"> </Canvas> </Window> /// code behind public partial class MainWindow : Window { private Boolean isMouseCapture; public MainWindow() { InitializeComponent(); } void MainWindow_Loaded(object sender, RoutedEventArgs e) { this.ParentCanvas.MouseLeftButtonDown += new MouseButtonEventHandler(_MouseLeftButtonDown); this.ParentCanvas.MouseLeftButtonUp += new MouseButtonEventHandler(_MouseLeftButtonUp); this.ParentCanvas.MouseMove += new MouseEventHandler(_MouseMove); } void _MouseLeftButtonUp(object sender, MouseButtonEventArgs e) { this.ParentCanvas.ReleaseMouseCapture(); isMouseCapture = false; } void _MouseLeftButtonDown(object sender, MouseButtonEventArgs e) { this.ParentCanvas.CaptureMouse(); isMouseCapture = true; } void _MouseMove(object sender, MouseEventArgs e) { if (isMouseCapture) { this.ParentCanvas.X= e.GetPosition(this).X; this.ParentCanvas.Y = e.GetPosition(this).Y; } } } 'X' is not a property of Canvas (i.e."this.ParentCanvas.X"). What do I use to set the position?

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  • There is already an open Datareader associated in C#

    - by Celine
    I can't seem to find the reason behind this error. Can someone look into my codes? private void button2_Click_1(object sender, EventArgs e) { con.Open(); string check = "Select block, section, size from interment_location where block='" + textBox12.Text + "' and section='" + textBox13.Text + "' and size='" + textBox14.Text + "'"; SqlCommand cmd1 = new SqlCommand(check, con); SqlDataReader rdr; rdr = cmd1.ExecuteReader(); try { if (textBox1.Text == "" || textBox2.Text == "" || textBox3.Text == "" || textBox4.Text == "" || textBox7.Text == "" || textBox8.Text == "" || textBox9.Text == "" || textBox10.Text == "" || dateTimePicker1.Value.ToString("yyyyMMdd HH:mm:ss") == "" || dateTimePicker2.Value.ToString("yyyyMMdd HH:mm:ss") == "" || textBox11.Text == "" || dateTimePicker3.Value.ToString("yyyyMMdd HH:mm:ss") == "" || textBox12.Text == "" || textBox13.Text == "" || textBox14.Text == "") { MessageBox.Show( "Please input a value!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation); } else if (rdr.HasRows == true) { MessageBox.Show("Interment Location is already reserved."); textBox12.Clear(); textBox13.Clear(); textBox14.Clear(); textBox12.Focus(); } else if (MessageBox.Show( "Are you sure you want to reserve this record?", "Reserve", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes) { SqlCommand cmd4 = new SqlCommand( "insert into owner_info(ownerf_name, ownerm_name," + " ownerl_name, home_address, tel_no, office)" + " values('" + textBox1.Text + "', '" + textBox2.Text + "', '" + textBox3.Text + "', '" + textBox4.Text + "', '" + textBox7.Text + "', '" + textBox8.Text + "')", con); cmd.ExecuteNonQuery(); SqlCommand cmd5 = new SqlCommand( "insert into deceased_info(deceased_id, name_of_deceased, " + "address, do_birth, do_death, place_of_death, " + "date_of_interment, COD_id, place_of_vigil_id, " + "service_id, owner_id) values('" + ownerid + "','" + textBox9.Text + "', '" + textBox10.Text + "', '" + dateTimePicker1.Value.ToString("yyyyMMdd HH:mm:ss") + "', '" + dateTimePicker2.Value.ToString("yyyyMMdd HH:mm:ss") + "', '" + textBox11.Text + "', '" + dateTimePicker3.Value.ToString("yyyyMMdd HH:mm:ss") + "', '" + ownerid + "', '" + ownerid + "', '" + ownerid + "', '" + ownerid + "')", con); cmd.ExecuteNonQuery(); SqlCommand cmd6 = new SqlCommand( "insert into interment_location(lot_no, block, section, " + "size, garden_id) values('" + ownerid + "','" + textBox12.Text + "', '" + textBox13.Text + "', '" + textBox14.Text + "', '" + ownerid + "')", con); cmd.ExecuteNonQuery(); MessageBox.Show( "Your reservation has been made!", "Reserve", MessageBoxButtons.OK, MessageBoxIcon.Information); } } catch (Exception x) { MessageBox.Show(x.Message); } con.Close(); } This is the only code that I edited after.

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