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  • Ajax not working in visual studio 2005

    - by sachin
    I am trying to do an ajax website, but my ajax is not working. I checked my GAC and system.web,extensions dll is available. Why it is not working .? I am also not getting any errors. I tried many ways. I wrote the below code to test ajax. <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %> <%@ Register Assembly="System.Web.Extensions" Namespace="System.Web.UI" TagPrefix="asp" %> <%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>Untitled Page</title> </head> <body> <form id="form1" runat="server"> <div> <cc1:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"> </cc1:ToolkitScriptManager> <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> <cc1:CalendarExtender ID="CalendarExtender1" runat="server" TargetControlID="TextBox1"> </cc1:CalendarExtender> </div> </form> </body> </html> JAvascript error that i got 1.Type is not defined http://localhost:1467/testnew/Default.aspx?_TSM_HiddenField_=ToolkitScriptManager1_HiddenField&_TSM_CombinedScripts_=%3b%3bAjaxControlToolkit%2c+Version%3d1.0.20229.20821%2c+Culture%3dneutral%2c+PublicKeyToken%3d28f01b0e84b6d53e%3aen-US%3ac5c982cc-4942-4683-9b48-c2c58277700f%3ae2e86ef9%3aa9a7729d%3a9ea3f0e2%3a9e8e87e9%3a1df13a87%3a4c9865be%3aba594826%3a507fcf1b%3ac7a4182e

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  • Cannot inherit from generic base class and specific interface using same type with generic constrain

    - by simendsjo
    Sorry about the strange title. I really have no idea how to express it any better... I get an error on the following snippet. I use the class Dummy everywhere. Doesn't the compiler understand the constraint I've added on DummyImplBase? Is this a compiler bug as it works if I use Dummy directly instead of setting it as a constraint? Error 1 'ConsoleApplication53.DummyImplBase' does not implement interface member 'ConsoleApplication53.IRequired.RequiredMethod()'. 'ConsoleApplication53.RequiredBase.RequiredMethod()' cannot implement 'ConsoleApplication53.IRequired.RequiredMethod()' because it does not have the matching return type of 'ConsoleApplication53.Dummy'. C:\Documents and Settings\simen\My Documents\Visual Studio 2008\Projects\ConsoleApplication53\ConsoleApplication53\Program.cs 37 27 ConsoleApplication53 public class Dummy { } public interface IRequired<T> { T RequiredMethod(); } public interface IDummyRequired : IRequired<Dummy> { void OtherMethod(); } public class RequiredBase<T> : IRequired<T> { public T RequiredMethod() { return default(T); } } public abstract class DummyImplBase<T> : RequiredBase<T>, IDummyRequired where T: Dummy { public void OtherMethod() { } }

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  • FileHelpers cannot map converted field into destination array

    - by jaffa
    I have the following record (reduced for brevity): [DelimitedRecord(",")] [IgnoreFirst] [IgnoreEmptyLines()] public class ImportRecord { [FieldQuoted] [FieldTrim(TrimMode.Both)] public string FirstName; [FieldQuoted] [FieldTrim(TrimMode.Both)] public string LastName; [FieldQuoted] [FieldTrim(TrimMode.Both)] [FieldOptional] [FieldConverter(typeof(TestPropertyConverter))] public int[] TestProperty; } Converter code: public class TestPropertyConverter : ConverterBase { public override object StringToField(string from) { var ret = from.Split('|').Select(x => Convert.ToInt32(x)).ToArray(); return ret; } } So an example record could be: John, Smith, 1|2|3|4 It would expect the values 1,2,3,4 to expand and fill the TestProperty array. However, I'm getting the following exception: At least one element in the source array could not be cast down to the destination array type. I've tried to debug into the code and it seems to blow-up in the ExtractFieldValue() function inside FieldBase.cs where it tries to return out of the function. The following line seems to be the culprit: res.ToArray(ArrayType); It seems to expect the 'res' variable to be the destination type array, but it contains 1 element of the array itself. Can anyone suggest if I'm doing this wrong or a possible fix?

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  • jquery lightbox multiple items to look like mac dashboard

    - by Don
    Hope the title says it all... I'm wondering if it's possible in any existing lightbox to pop up a look similar to the mac dashboard where multiple divs could be "on" in the front with the main webpage with a gray overlay. Basically something where a user clicks an icon on the main webpage to call, and then 4 separate content boxes are popped on top, but not in a window like a gallery. I'm thinking the top background used could be set to transparent and the individual items could be divs on the popped area, but before I reinvent the wheel, I thought I'd see if there's something like this that I just haven't found in my searches. UPDATE: 1/7/2011 I ended up using colorbox with a background behind my divs. It doesn't look like the mac with items having the bg behind them showing between them, but after talking to the designer I'm working with, that wasn't something they really needed anyhow. I think it MAY be possible changing some of the CSS though for the bg of the "popped" window. Colorbox seems to be pretty nice about making it clear what the CSS is doing and there are multiple example skins. Just my $0.02...

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  • Generic validate input data via regex. Input error when match.count == 0

    - by Valamas
    Hi, I have a number of types of data fields on an input form, for example, a web page. Some fields are like, must be an email address, must be a number, must be a number between, must have certain characters. Basically, the list is undefinable. I wish to come up with a generic way of validating the data inputed. I thought I would use regex to validate the data. The fields which need validation would be related to a "regex expression" and a "regex error message" stating what the field should contain. My current mock up has that when the match count is zero, that would signify an error and to display the message. While still a white belt regex designer I have come to understand that in certain situations that it is difficult to write a regex which results in a match count of zero for every case. A complex regex case I looked for help on was Link Here. The forum post was a disaster because I confused people helping me. But one of the statements said that it was difficult to make a regex with a match count of zero meaning the input data was invalid; that the regex was very difficult to write that for. Does anyone have comments or suggestions on this generic validation system I am trying to create? thanks

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  • What are Sharepoint(MOSS 2007) Developement/Deployment best practices.

    - by Satish
    We are deploying sharepoint MOSS 2007 at our work. I'm trying to come up with a sharepoint development and deployment methodology. We have Dev/QA/Prod environments and I need a way, preferably automated to deploy changes from Dev to QA and from there to prod. We are creating site collections web parts etc. Some of it is done directly within sharepoint, some through Sharepoint designer or visual studio. I'm looking for a way to extract this and deploy it to other enviornments. I tried stsadm backup/restore import/export etc but they all move the data along with it as well. I just need the structure deployed. Content deployment paths and jobs does the same thing as well. We use MSBuild & Curisecontrol.net for other .net projects to automate build/deployment process. I'm looking for something similar with sharepoint if possible. What are your best practices for this? Since my team is learning we don't have a defined process and we are open to change our development process if needed.

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  • Get more error information from unhandled error

    - by Andrew Simpson
    I am using C# in a desktop application. I am calling a DLL written in C that I do not have the source code for. Whenever I call this DLL I get an untrapped error which I trap in an UnhandledException event/delegate. The error is : object reference not set to an instance of an object But the stack trace is empty. When I Googled this the info back was that the error was being hanlded eleswhere and then rethrown. But this can only be in the DLL I do not have the source code for. So, is there anyway I can get more info about this error? This is my code... in program.cs... AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException); static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e) { try { Exception _ex = (Exception)e.ExceptionObject; //the stact trace property is empty here.. } finally { Application.Exit(); } } My DLL... [DllImport("AutoSearchDevice.dll", EntryPoint = "Start", ExactSpelling = false, CallingConvention = CallingConvention.StdCall)] public static extern int Start(int ASD_HANDLE); An I call it like so: public static void AutoSearchStart() { try { Start(m_pASD); } catch (Exception ex) { } }

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  • JQuery - Microsoft JScript runtime error: Object expected

    - by ydobonmai
    Below is the content of my .aspx page and the "jquery-ui-1.7.1.custom.min.js" is in the same location as the .aspx file. When I run the website with debugging, I get the below error. I know I am terribly missing something here. Any clue? Error :- Microsoft JScript runtime error: Object expected When I run without debugging, I get the following javascript error:- Line: 10 Error: 'jQuery' is undefined ASPX page content:- <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default3.aspx.cs" Inherits="Default3" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <script src="jquery-ui-1.7.1.custom.min.js" type="text/javascript"></script> </head> <body> <form id="form1" runat="server"> <div> <script>$(function () { alert('hello') });</script> </div> </form> </body> </html>

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  • Need help with a simple ASP.NET ModalPopupExtender example

    - by remdao
    I'm new to ASP.NET and I'm trying to get this Ajax ModalPopupExtender working. This is an example i found on the net, but nothing happens when btnpopup is clicked. <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="ModalTestProject._Default" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>Untitled Page</title> </head> <body> <form id="form1" runat="server"> <asp:scriptmanager id="ScriptManager1" runat="server"> </asp:scriptmanager> <asp:Button ID="btnpopup" runat="server" Text="Button" /> <ajaxToolkit:ModalPopupExtender ID="mpe" runat="server" TargetControlID="btnpopup" PopupControlID="pnlpopup" CancelControlID="btnCancelpopup" EnableViewState="true" DropShadow="true" /> <asp:Panel ID="pnlpopup" runat="server" Width="400px"> test <asp:Button ID="btnCancelpopup" runat="server" Text="Button" /> </asp:Panel> </form> </body> </html>

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  • Writing to a new log file each day with TraceSource

    - by Cipher
    I am using a logger in my application to write to files. The source, switch and listeners have been defined in the app.config file as follows: <system.diagnostics> <sources> <source name="LoggerApp" switchName="sourceSwitch" switchType="System.Diagnostics.SourceSwitch"> <listeners> <add name="myListener" type="System.Diagnostics.TextWriterTraceListener" initializeData="myListener.log" /> </listeners> </source> </sources> <switches> <add name="sourceSwitch" value="Information" /> </switches> </system.diagnostics> Inside, my .cs code, I use the logger as follows: private static TraceSource logger = new TraceSource("LoggerApp"); logger.TraceEvent(TraceEventType.Information, 1, "{0} : Started the application", DateTime.Now); What would I have to do to create a new log file each day instead of writing to the same log file every time?

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  • CSS - vertical align text where text can be multiple lines

    - by Sniffer
    Hi all I've been given a design by a graphic designer, which I'm trying to put into HTML and CSS. One of the issues I'm facing is on a user input form. In the design the labels for each input are a fixed width - say 100px. The container for each label/input pair is fixed at 2em. The design I've been given has asked that the text for each label is vertically aligned. So the structure is like this: <containerTag> <label /> <input /> </containerTag> No problems as long as the text is on one line (I would have just used line-height of 2em to match the container), but some of the text in the labels are wrapping to two or even lines. Is there a semantic and nice way to get around this problem? I need something that will work in IE6-9, Firefox 3.5+, Chrome and Safari. Although I am using progressive enhancement, so if there is a solution that will only work on the later browsers, but won't break the older ones, then this would be acceptable. Any help gratefully received! Thanks for your time S

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  • Spawning vim from a node git hook

    - by Lawrence Jones
    I've got a project purely in coffeescript, with git hooks for deployment also written in cs. I don't really want to break away from the language just to use bash for a quick commit message formatter, but I've got a problem spawning vim from the commit-msg hook. I've seen here that when piping to vim, the stdio is not necessarily set correctly to the tty streams. I get how that could cause a problem, but I don't exactly know how to get vim to load correctly using nodes spawn command. At the moment I have... vim = (require 'child_process').spawn('vim', [file], stdio: 'inherit') vim.on 'exit', (err) -> console.log "Exited! [#{err}]" cb?() ...which works fine to spawn a vim process that can r/w from the parents stdio, but when I use this in the hook things go wrong. Vim states that the stdio is not from terminal, and then once opened typing causes escape characters to pop up all over the place. Backspace for example, will produce ^?. Any help would be appreciated!

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  • NHibernate.MappingException on table insertion.

    - by Suja
    The table structure is : The controller action to insert a row to table is public bool CreateInstnParts(string data) { IDictionary myInstnParts = DeserializeData(data); try { HSInstructionPart objInstnPartBO = new HSInstructionPart(); using (ISession session = Document.OpenSession()) { using (ITransaction transaction = session.BeginTransaction()) { objInstnPartBO.DocumentId = Convert.ToInt32(myInstnParts["documentId"]); objInstnPartBO.InstructionId = Convert.ToInt32(myInstnParts["instructionId"]); objInstnPartBO.PartListId = Convert.ToInt32(myInstnParts["part"]); objInstnPartBO.PartQuantity = Convert.ToInt32(myInstnParts["quantity"]); objInstnPartBO.IncPick = Convert.ToBoolean(myInstnParts["incpick"]); objInstnPartBO.IsTracked = Convert.ToBoolean(myInstnParts["istracked"]); objInstnPartBO.UpdatedBy = User.Identity.Name; objInstnPartBO.UpdatedAt = DateTime.Now; session.Save(objInstnPartBO); transaction.Commit(); } return true; } } catch (Exception ex) { Console.Write(ex.Message); return false; } } This is throwing an exception NHibernate.MappingException was caught Message="No persister for: Hexsolve.Data.BusinessObjects.HSInstructionPart" Source="NHibernate" StackTrace: at NHibernate.Impl.SessionFactoryImpl.GetEntityPersister(String entityName) at NHibernate.Impl.SessionImpl.GetEntityPersister(String entityName, Object obj) at NHibernate.Event.Default.AbstractSaveEventListener.SaveWithGeneratedId(Object entity, String entityName, Object anything, IEventSource source, Boolean requiresImmediateIdAccess) at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.SaveWithGeneratedOrRequestedId(SaveOrUpdateEvent event) at NHibernate.Event.Default.DefaultSaveEventListener.SaveWithGeneratedOrRequestedId(SaveOrUpdateEvent event) at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.EntityIsTransient(SaveOrUpdateEvent event) at NHibernate.Event.Default.DefaultSaveEventListener.PerformSaveOrUpdate(SaveOrUpdateEvent event) at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.OnSaveOrUpdate(SaveOrUpdateEvent event) at NHibernate.Impl.SessionImpl.FireSave(SaveOrUpdateEvent event) at NHibernate.Impl.SessionImpl.Save(Object obj) at HexsolveMVC.Controllers.InstructionController.CreateInstnParts(String data) in F:\Project\HexsolveMVC\Controllers\InstructionController.cs:line 1342 InnerException: Can anyone help me solve this??

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  • MACRO compilation PROBLEM

    - by wildfly
    i was given a primitive task to find out (and to put in cl) how many nums in an array are bigger than the following ones, (meaning if (arr[i] arr[i+1]) count++;) but i've problems as it has to be a macro. i am getting errors from TASM. can someone give me a pointer? SortA macro a, l LOCAL noes irp reg, <si,di,bx> push reg endm xor bx,bx xor si,si rept l-1 ;;also tried rept 3 : wont' compile mov bl,a[si] inc si cmp bl,arr[si] jb noes inc di noes: add di,0 endm mov cx,di irp reg2, <bx,di,si> pop reg2 endm endm dseg segment arr db 10,9,8,7 len = 4 dseg ends sseg segment stack dw 100 dup (?) sseg ends cseg segment assume ds:dseg, ss:sseg, cs:cseg start: mov ax, dseg mov ds,ax sortA arr,len cseg ends end start errors: Assembling file: sorta.asm **Error** sorta.asm(51) REPT(4) Expecting pointer type **Error** sorta.asm(51) REPT(6) Symbol already different kind: NOES **Error** sorta.asm(51) REPT(10) Expecting pointer type **Error** sorta.asm(51) REPT(12) Symbol already different kind: NOES **Error** sorta.asm(51) REPT(16) Expecting pointer type **Error** sorta.asm(51) REPT(18) Symbol already different kind: NOES Error messages: 6

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  • asp.net custom control with form field validation issue

    - by Ibrar Afzal
    Hi, I have created a custom asp .net control some fields have validation controal associated with them. The problem arised when I declare more than one initializtion on a page. When I hit submit on one of the intialized control. Form validation occur on all other control that were declared. Due to this issue I can submit a for. Here is the code `<%@ Control Language="C#" AutoEventWireup="true" CodeFile="FinancialAdvisorHelp.ascx.cs" Inherits="FinancialAdvisorHelp" %                                           Invalid Email." Member Name* E-Mail Address* Telephone Number Ask Darryl your question Note: you should receive a response within two (2) business days. *Required information.   `

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  • MVVM and avoiding Monolithic God object

    - by bufferz
    I am in the completion stage of a large project that has several large components: image acquisition, image processing, data storage, factory I/O (automation project) and several others. Each of these components is reasonably independent, but for the project to run as a whole I need at least one instance of each component. Each component also has a ViewModel and View (WPF) for monitoring status and changing things. My question is the safest, most efficient, and most maintainable method of instantiating all of these objects, subscribing one class to an Event in another, and having a common ViewModel and View for all of this. Would it best if I have a class called God that has a private instance of all of these objects? I've done this in the past and regretted it. Or would it be better if God relied on Singleton instances of these objects to get the ball rolling. Alternatively, should Program.cs (or wherever Main(...) is) instantiate all of these components, and pass them to God as parameters and then let Him (snicker) and His ViewModel deal with the particulars of running this projects. Any other suggestions I would love to hear. Thank you!

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  • Does not contain a definition

    - by JB
    public void button2_Click(object sender, System.EventArgs e) { string text = textBox1.Text; Mainform = this; this.Hide(); GetSchedule myScheduleFinder = new GetSchedule(); string result = myScheduleFinder.GetDataFromNumber(text);// says there is no definition if (!string.IsNullOrEmpty(result)) { MessageBox.Show(result); } else { MessageBox.Show("Enter A Valid ID Number!"); } } says it does not contain definition for it but on my GetSchedule .cs file i have it defined public string GetDataFromNumber(string ID)//defined here { foreach (IDnumber IDCandidateMatch in IDnumbers) { if (IDCandidateMatch.ID == ID) { StringBuilder myData = new StringBuilder(); myData.AppendLine(IDCandidateMatch.Name); myData.AppendLine(": "); myData.AppendLine(IDCandidateMatch.ID); myData.AppendLine(IDCandidateMatch.year); myData.AppendLine(IDCandidateMatch.class1); myData.AppendLine(IDCandidateMatch.class2); myData.AppendLine(IDCandidateMatch.class3); myData.AppendLine(IDCandidateMatch.class4); //return myData; return myData.ToString(); } } return ""; } } } }

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  • JSTL <c:out> where the element name contains a space character...

    - by Shane
    I have an array of values being made available, but unfortunately some of the variable names include a space. I cannot work out how to simply output these in the page. I know I'm not explaining this well (I'm the JSP designer, not the Java coder) so hopefully this example will illustrate what I'm trying to do: <c:out value="${x}"/> outputs to the page (artificially wrapped) as: {width=96.0, orderedheight=160.0, instructions=TEST ONLY. This is a test., productId=10132, publication type=ns, name=John} I can output the name by using <c:out value="${x.name}"/> no problems. The issue is when I try to get the "publication type"... because it has a space, I can't seem to get <c:out> to display it. I have tried: <!-- error parsing custom action attribute: --> <c:out value="${x.publication type}"/> <!-- error occurred while evaluating custom action attribute: --> <c:out value="${x.publication+type}"/> <!-- error occurred while parsing custom action attribute: --> <c:out value="${x.'publication type'}"/> <!-- error occurred while parsing custom action attribute: --> <c:out value="${x.publication%20type}"/> I know the real solution is to get the variable names formatted correctly (ie: without spaces) but I can't get the code updated for quite a while. Can this be done? Any help greatly appreciated.

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  • Dealing with Expression Blend's lack of support for C++/CLI projects

    - by Brian Ensink
    I have a WPF C# project that references a C++/CLI mixed mode project. I'm having trouble using the WPF project in Expression Blend 3. I'm new to Blend so perhaps this is obvious, but it won't display the xaml designer properly until it builds the project. In my case it complains that my custom commands are not "recognized or accessible" and the solution is to build the project in Blend. But I can't build the project because it references a C++/CLI mixed mode project which Blend won't load. The WPF project is pure C# it just happens to reference a C++/CLI mixed mode project but I'm not asking Blend to do anything with the mixed-mode assembly. How can I work around this problem? Edit: I was able to get it to build by removing the reference to the C++/CLI mixed mode project and replacing it with a reference to the actual assembly. However this is not ideal because in my past experience Visual Studio will not always be able to resolve the reference when switching between release and debug configurations.

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  • C#: Non-constructed generics as properties (eg. List<T>)

    - by Dav
    The Problem It's something I came across a while back and was able to work around it somehow. But now it came back, feeding on my curiosity - and I'd love to have a definite answer. Basically, I have a generic dgv BaseGridView<T> : DataGridView where T : class. Constructed types based on the BaseGridView (such as InvoiceGridView : BaseGridView<Invoice>) are later used in the application to display different business objects using the shared functionality provided by BaseGridView (like virtual mode, buttons, etc.). It now became necessary to create a user control that references those constructed types to control some of the shared functionality (eg. filtering) from BaseGridView. I was therefore hoping to create a public property on the user control that would enable me to attach it to any BaseGridView in Designer/code: public BaseGridView<T> MyGridView { get; set; }. The trouble is, it doesn't work :-) When compiled, I get the following message: The type or namespace name 'T' could not be found (are you missing a using directive or an assembly reference?) Solutions? I realise I could extract the shared functionality to an interface, mark BaseGridView as implementing that interface, and then refer to the created interface in my uesr control. But I'm curious if there exists some arcane C# command/syntax that would help me achieve what I want - without polluting my solution with an interface I don't really need :-)

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  • ASP.NET MVC 2 - Custom route doesn't find controller action

    - by mcfroob
    For some reason my application isn't routing to my controller method correctly. I have a routelink like this in my webpage - <%= Html.RouteLink("View", "Blog", new { id=(item.BlogId), slug=(item.Slug) }) %> In global.asax.cs I have the following routes - routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapRoute( "MoreBlogs", "Blog/Page/{page}", new { controller = "Blog", action = "Index" } ); routes.MapRoute( "Blog", "Blog/View/{id}/{slug}", new { controller = "Blog", action = "View"} ); routes.MapRoute( "Default", // Route name "{controller}/{action}/{id}", // URL with parameters new { controller = "Blog", action = "Index", id = UrlParameter.Optional } // Parameter defaults ); And then I have a class BlogController that has a method - public ActionResult View(int id, string slug) { ... etc. } I put a breakpoint in the first line of the View method but it's not getting hit at all. I checked with a route debugger for the format localhost/Blog/View/1/test and it matched my custom route. All I'm getting is a 404 while running this, I can't work out why the route won't post to the view method in my controller - any ideas?

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  • Appropriate uses of Monad `fail` vs. MonadPlus `mzero`

    - by jberryman
    This is a question that has come up several times for me in the design code, especially libraries. There seems to be some interest in it so I thought it might make a good community wiki. The fail method in Monad is considered by some to be a wart; a somewhat arbitrary addition to the class that does not come from the original category theory. But of course in the current state of things, many Monad types have logical and useful fail instances. The MonadPlus class is a sub-class of Monad that provides an mzero method which logically encapsulates the idea of failure in a monad. So a library designer who wants to write some monadic code that does some sort of failure handling can choose to make his code use the fail method in Monad or restrict his code to the MonadPlus class, just so that he can feel good about using mzero, even though he doesn't care about the monoidal combining mplus operation at all. Some discussions on this subject are in this wiki page about proposals to reform the MonadPlus class. So I guess I have one specific question: What monad instances, if any, have a natural fail method, but cannot be instances of MonadPlus because they have no logical implementation for mplus? But I'm mostly interested in a discussion about this subject. Thanks! EDIT: One final thought occured to me. I recently learned (even though it's right there in the docs for fail) that monadic "do" notation is desugared in such a way that pattern match failures, as in (x:xs) <- return [] call the monad's fail. It seems like the language designers must have been strongly influenced by the prospect of some automatic failure handling built in to haskell's syntax in their inclusion of fail in Monad.

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  • SIlverlight Navigate: how does it work? How would you implement in f# w/o VS wizards and helpers?

    - by akaphenom
    After a nights sleep the problem can be stated more accurately as I have a 100% f# / silverlight implementation and am looking to use the built in Navigation components. C# creates page.xaml and page.xaml.cs um - ok; but what is the relationship at a fundamental level? How would I go about doing this in f#? The applcuation is loaded in the default module, and I pull the XAML in and reference it from the application object. Do I need to create instances / references to the pages from within the application object? Or set up some other page management object with the proper name value pairs? When all the Help of VS is stripped away - what are we left with? original post (for those who may be reading replies) I have a 100% silverlight 3.0 / f# 2.0 application I am wrapping my brain around. I have the base application loading correctly - and now I want to add the naigation controls to it. My page is stored as an embedded resource - but the Frame.Navigate takes a URI. I know what I have is wrong but here it is: let nav : Frame = mainGrid ? mainFrame let url = "/page1.xaml" let uri = new System.Uri(url, System.UriKind.Relative) ; nav.Navigate uri Any thoughts?

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  • Three most critical programming concepts

    - by Todd
    I know this has probably been asked in one form or fashion but I wanted to pose it once again within the context of my situation (and probably others here @ SO). I made a career change to Software Engineering some time ago without having an undergrad or grad degree in CS. I've supplemented my undergrad and grad studies in business with programming courses (VB, Java,C, C#) but never performed academic coursework in the other related disciplines (algorithms, design patterns, discrete math, etc.)...just mostly self-study. I know there are several of you who have either performed interviews and/or made hiring decisions. Given recent trends in demand, what would you say are the three most essential Comp Sci concepts that a developer should have a solid grasp of outside of language syntax? For example, I've seen blog posts of the "Absolute minimum X that every programmer must know" variety...that's what I'm looking for. Again if it's truly a redundancy please feel free to close; my feelings won't be hurt. (Closest ones I could find were http://stackoverflow.com/questions/164048/basic-programming-algorithmic-concepts- which was geared towards a true beginner, and http://stackoverflow.com/questions/648595/essential-areas-of-knowledge-which I didn't feel was concrete enough). Thanks in advance all! T.

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  • Conversion failed when converting datetime from character string

    - by salvationishere
    I am developing a C# VS 2008 / SQL Server 2005 Express website application. I have tried some of the fixes for this problem but my call stack differs from others. And these fixes did not fix my problem. What steps can I take to troubleshoot this? Here is my error: System.Data.SqlClient.SqlException was caught Message="Conversion failed when converting datetime from character string." Source=".Net SqlClient Data Provider" ErrorCode=-2146232060 LineNumber=10 Number=241 Procedure="AppendDataCT" Server="\\\\.\\pipe\\772EF469-84F1-43\\tsql\\query" State=1 StackTrace: at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection) at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at ADONET_namespace.ADONET_methods.AppendDataCT(DataTable dt, Dictionary`2 dic) in c:\Documents and Settings\Admin\My Documents\Visual Studio 2008\WebSites\Jerry\App_Code\ADONET methods.cs:line 102 And here is the related code. When I debugged this code, "dic" only looped through the 3 column names, but did not look into row values which are stored in "dt", the Data Table. public static string AppendDataCT(DataTable dt, Dictionary<string, string> dic) { if (dic.Count != 3) throw new ArgumentOutOfRangeException("dic can only have 3 parameters"); string connString = ConfigurationManager.ConnectionStrings["AW3_string"].ConnectionString; string errorMsg; try { using (SqlConnection conn2 = new SqlConnection(connString)) { using (SqlCommand cmd = conn2.CreateCommand()) { cmd.CommandText = "dbo.AppendDataCT"; cmd.CommandType = CommandType.StoredProcedure; cmd.Connection = conn2; foreach (string s in dic.Keys) { SqlParameter p = cmd.Parameters.AddWithValue(s, dic[s]); p.SqlDbType = SqlDbType.VarChar; } conn2.Open(); cmd.ExecuteNonQuery(); conn2.Close(); errorMsg = "The Person.ContactType table was successfully updated!"; } } }

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