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  • How can I ensure that nested transactions are committed independently of each other?

    - by Caldera
    If I have a stored procedure that executes another stored procedure several times with different arguments, is it possible to have each of these calls commit independently of the others? In other words, if the first two executions of the nested procedure succeed, but the third one fails, is it possible to preserve the results of the first two executions (and not roll them back)? I have a stored procedure defined something like this in SQL Server 2000: CREATE PROCEDURE toplevel_proc .. AS BEGIN ... while @row_count <= @max_rows begin select @parameter ... where rownum = @row_count exec nested_proc @parameter select @row_count = @row_count + 1 end END

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  • why is this legal, c++ typedef func

    - by acidzombie24
    i did this in msvc 2005. typedef void (*cleanup_t)(); void func(cleanup_t clean) { cleanup_t(); } Why does this compile? and not give me a warning? ok, it gave me a unreferenced formal parameter warning but originally i did this when clean was in a class no there was no unreferenced formal parameter when this code gave me problems. What is cleanup_t(); really doing and what is the point? now for laughs i tried int() and that worked also.

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  • Dataset Binding stored procedures update/insert/delete

    - by Jin
    Hi all, I am currently having a problem since the DB has been changed. I am using Datasets for a c# application, and there is a user management system. For the security issues, our current DB design is like user log into app. DB returns a session ID On use of any other stored procedures, a session ID must be specified. BUT, the DB didn't request session ID before. since I am using the datasets, I used update/insert/delete stored procedures with "TableAdaptor Configuration Wizard". Bind Commands to Existing Stored Procedures (choose stored procedures to call and specify any reuiqred parameters) Now, it seems like I have to specify session ID for Insert/Update/Delete stored procedures. How do I specify session ID parameter here? It seems like I have to pick one return parameter variable from a select statement. Thanks,

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  • Call an AsyncTask inside a Thread

    - by Arun
    I am working in an android application and I want to call an AsyncTask from my UI main thread. For that I want to call my AsyncTask from a thread. This is the method that I call from my main UI thread. This is working correctly CommonAysnk mobjCommonAysnk = new CommonAysnk(this, 1); mobjCommonAysnk.execute(); CommonAysnk is my AsyncTask class.I want to pass my activity and an integer parameter to the AsyncTask constructor. How can I call this from a thread as shown below method. Thread t = new Thread() { public void run() { try { CommonAysnk mobjCommonAysnk = new CommonAysnk(this, 1); mobjCommonAysnk.execute(); } catch (Exception ex) { }}}; t.start(); When I tried to call it from a Thread and I am not able to pass the activity parameter correctly. How can we sole this. Thanks

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  • Placing the where condition

    - by user182944
    I came up with the below query: SELECT ROOMNO,BUILDINGNO FROM MRM_ROOM_DETAILS WHERE ROOMID IN ( SELECT distinct roomid FROM MRM_BOOKING_DETAILS WHERE (CHECKIN NOT BETWEEN '2012-04-13 09:50:00' AND '2012-04-13 10:20:00') AND (CHECKOUT NOT BETWEEN '2012-04-13 09:50:00' AND '2012-04-13 10:20:00')) AND CAPACITY > 15 AND PROJECTIONSTATUS = 'NO'; I need to place this query in the method SQLiteDatabase.query() and fetch the rows accordingly. I am not able to understand how to place this big where condition (which contains a sub-query as well) in place of the "String selection" i.e. 3rd parameter of the method. Shall i simple write the entire where part(including the sub-query) as a string in the 3rd parameter or else there is some other better way for doing the same? Please suggest me the best way to do the same. Regards,

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  • Passing parameters among views in a navigation frame INSIDE a custom control

    - by NetWriter
    I created a silverlight 3 application with a navigation frame and 3 views: search, add and edit. I used the app file to pass parameters among the 3 pages, eg: ((App)Application.Current).SNIPSELECTED = currentSnip; Then in the receiving page: currentSnip = ((App)Application.Current).SNIPSELECTED; currentSnip is a SnipItem object: public class SnipItem { public string itemID {get;set;} public string category {get;set;} public string itemDescription {get;set;} public string codeSnip {get;set;} } This worked fine until I decided to make this entire application into a user control and put that inside a second silverlight application with its own navigation frame and app file. The app files are getting confused. The first app file with all my parameter passing is not being read. I know how to pass a simple parameter between views in the first application without the app file (in a query string), but how about these custom types like my currentSnip above?

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  • Template or function arguments as implementation details in doxygen?

    - by Vincent
    In doxygen is there any common way to specify that some C++ template parameters of function parameters are implementation details and should not be specified by the user ? For example, a template parameter used as recursion level counter in metaprogramming technique or a SFINAE parameter in a function ? For example : /// \brief Do something /// \tparam MyFlag A flag... /// \tparam Limit Recursion limit /// \tparam Current Recursion level counter. SHOULD NOT BE EXPLICITELY SPECIFIED !!! template<bool MyFlag, unsigned int Limit, unsigned int Current = 0> myFunction(); Is there any doxygen normalized option equivalent to "SHOULD NOT BE EXPLICITELY SPECIFIED !!!" ?

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  • Why does FrameworkElement's FindResource() Method Accept an Object and not a String?

    - by ChrisNel52
    I understand that calling FindResource() on a FrameworkElement (e.g. a Window) can be used to find a resource in the FrameworkElement's ResourceDictionary. For example, I've used it many times to access a Style through code to add a new Setter to the Style dynamically. I always pass the x:Key value of the Style as a string into the FindResource() method. Like... Style style = w.FindResource("GridDescriptionColumn") as Style; My question is, I noticed that FindResource() accepts an argument of type object and not an argument of type string. I can't for the life of my think of a reason I would call FindResource() with an argument that is not a string. It makes me think that I may unaware of other ways to use FindResource(). Does anyone know why FindResource() accepts a parameter type of object and not string? If so, what would be an example of calling FindResource() with a parameter type other than a string? Thanks.

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  • Django store regular expression in DB which then gets evaluated on page

    - by John
    Hi, I want to store a number of url patterns in my django model which a user can provide parameters to which will create a url. For example I might store these 3 urls in my db where %s is the variable parameter provided by the user: www.thisissomewebsite.com?param=%s www.anotherurl/%s/ www.lastexample.co.uk?param1=%s&fixedparam=2 As you can see from these examples the parameter can appear anywhere in the string and not in a fixed position. I have 2 models, one holds the urls and one holds the variables: class URLPatterns(models.Model): pattern = models.CharField(max_length=255) class URLVariables(models.Model): pattern = models.ForeignKey(URLPatterns) param = models.CharField(max_length=255) What would be the best way to generate these urls by replacing the %s with the variable in the database. would it just be a simple replace on the string e.g: urlvariable = URLVariable.objects.get(pk=1) pattern = url.pattern url = pattern.replace("%s", urlvariable.param) or is there a better way? Thanks

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  • Interesting XSL Dilemma

    - by bobber205
    I've got this issue. A template called "checkbox" that's called from while inside a table HTML element and also outside of it. To solve an issue, I've added tags to "checkbox" input control. Here's what I'd like to do to but I'm not sure if it's possible or not. When I hit my "row" (part of the custom table markup) template, I would set some variable or pass some parameter, that for each template applied afterwards, would know it was in a "row" and do something special based on this information. I know I can't add parameters to apply-templates. I may be able to add a row "mode" but I can't make changes to each template and have one copy with the mod parameter and one without. Thanks for any suggestions. I know the ideal solution would to be to make changes to the XML but I'm not sure if I can do that as this point. That's a "content" issue. :P Thanks!

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  • Recursion: using values passed in parameters

    - by Tom Lilletveit
    I got this line of code that pops a int of the array saves it to int element then removes it from array. then in the return statement return CountCriticalVotes(rest, blockIndex + element); it ads it to the blockIndex variable and if it reaches 10 before the array is empty it returns 1. But my problem is this, I do not want it to add up all the values in the array in the parameter, but only add one then revert the parameter value back to it´s original state, then add a new, revert etc... How would i do this? int NumCriticalVotes :: CountCriticalVotes(Vector<int> & blocks, int blockIndex) { if (blockIndex >= 10) { return 1; } if (blocks.isEmpty()) { return 0; } else { int element = blocks.get(0); Vector<int> rest = blocks; rest.remove(0); return CountCriticalVotes(rest, blockIndex + element);

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  • XmlResolver Class' GetEntity function

    - by Pok
    I wrote a custom resolver class. It works OK for resolving SYSTEM DTDs, but not for resolving PUBLIC DTDs. When the class has to resolve PUBLIC DTDs instead of the URI of the resource, the function receives the public identifier through the absoluteUri parameter of the GetEntity function. Is there a solution to this. In examples: if I have a DTD declaration like <!DOCTYPE document SYSTEM "document.dtd"> then the custom resolver correctly receives the string "document.dtd" through the absoluteUri parameter of the GetEntity function. if I have a DTD declaration like <!DOCTYPE document PUBLIC "-//Organization//DTD Document 1.0//EN" "http://localhost/document.dtd"> then the custom resolver incorrectly receives the string "-//Organization//DTD Document 1.0//EN" instead of "scheme://host/document.dtd".

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  • How to pass an object from a Frame to another Frame in a Windows 8 Style App

    - by Mythul
    I have problem that i just cant figure out right now. I am trying to develop a Windows-8 style app and im stuck implementing this functionality. I have a MainWindow which contains a ListBox and a Button (lets say addButton). When i click the button i navigate to a new page, lets say AddCustomerPage with this.Frame.Navigate(typeof (AddCustomerPage)); AddCustomerPage has 1 textBox and 1 button (lets say doneButton. When i click the button i want the string in the textBox to be added to the ListBox on the previous page. This is my current functionality: 1. MainWindow is created. Click addButton AddCustomer page is created. MainWindow is destroyed(problem). Click doneButton A MainWindow object is created with a ListBox with 1 item. Repeat the add process, i always get a MainWindow with a ListBox with 1 item. Thanks for the help. Here is the code: public sealed partial class MainPage : Page { public MainPage() { this.InitializeComponent(); this.brainPageController = new PageController(); // add items from the List<String> to the listBox listGoals.ItemsSource = brainPageController.GetListGoals(); } protected override void OnNavigatedTo(NavigationEventArgs e) { var parameter = e.Parameter as String; // a simple controller that adds a string to a List<string> brainPageController.AddGoal(parameter); } private void addButton_Click(object sender, RoutedEventArgs e) { this.Frame.Navigate(typeof (GoalsInfo)); } // VARIABLES DECLARATION private PageController brainPageController; } public sealed partial class GoalsInfo : WinGoalsWIP.Common.LayoutAwarePage { public GoalsInfo() { this.InitializeComponent(); this.brainPageController = new PageController(); } protected override void LoadState(Object navigationParameter, Dictionary<String, Object> pageState) { } protected override void SaveState(Dictionary<String, Object> pageState) { } private void Button_Click_1(object sender, RoutedEventArgs e) { brainPageController.AddGoal(nameTextBox.Text); this.Frame.Navigate(typeof(MainPage), nameTextBox.Text); } // VARIABLES DECLARATION PageController brainPageController; }

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  • Silverlight 4 Binding to ConverterParameter

    - by FrEEzE2046
    Hello everybody, I have a ValueConverter which needs to be called with a dynamic parameter, depending on a property. I can't see a way to do this ... Width="{Binding ActualWidthValue, Source={StaticResource VisibleSize}, Converter={StaticResource Fraction}}" The "Fraction" converter get's (or should get) a parameter of type System.Size, which contains a numerator and denumerator. This value (should) depend on a ItemCollection.Count. Resetting the ItemCollection should reinvoke the Converter with the new values. My first idea was to manually change the ConverterParameter in CodeBehind on the PropertyChanged event of my ItemCollection DependencyProperty. But, as I know now, Silverlight has no GetBinding() method. I heard about GetBindingExpression and tried to do. But MyGrid.GetBindingExpression(Grid.ActualHeightProperty) is always returning null, although the Binding is already established. So, what can I do to reach my target?

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  • Passing javascript to a function

    - by AJ
    Hello, Can I pass some Javascript to a function and then execute that Javascript from within the function, e.g. test("a = 1; b = 2; test2(a,b);"); function test(js) { // execute dynamically generated JS here. } Basically I have some code that is generated on the server and I want to pass that code to a JS function which when it has finished processing it executes the code passed as a parameter. This could also be useful for the parameter of setTimeout, then the code passed could be executed in the timeout event. Can this be done?

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  • Visual Basic Display Square

    - by user1724157
    Alright I'm currently lost on a particular assignment I have for a class. I've seen many examples of this app but none of them see to help my problem is as follows: Write a Sub procedure "DisplaySquare" to display the solid square. The size should be specified by the integer parameter "size". The character that fills the square should be specified by the string parameter "fillCharacter. Use a For...Next statement nested within another For...Next statement to create the square. The outer For...Next specifies what row is currently being displayed. The inner For...Next appends all the characters that form the row to a display string. So it should come out like as follows: if a user enters "8" and "#" ######## ######## ######## ######## ######## ######## ######## ######## Any help would be appreciated.

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  • Error occurs while using SPADE method in R

    - by Yuwon Lee
    I'm currently mining sequence patterns using SPADE algorithm in R. SPADE is included in "arulesSequence" package of R. I'm running R on my CentOS 6.3 64bit. For an exercise, I've tried an example presented in http://en.wikibooks.org/wiki/Data_Mining_Algorithms_In_R/Sequence_Mining/SPADE When I tried to do "cspade(x, parameter = list(support = 0.4), control = list(verbose = TRUE))" R says: parameter specification: support : 0.4 maxsize : 10 maxlen : 10 algorithmic control: bfstype : FALSE verbose : TRUE summary : FALSE preprocessing ... 1 partition(s), 0 MB [0.096s] mining transactions ... 0 MB [0.066s] reading sequences ...Error in asMethod(object) : 's' is not an integer vector When I try to run SPADE on my Window 7 32bit, it runs well without any error. Does anybody know why such errors occur?

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  • Update query (access & vb.net)

    - by yae
    Hi: I have to update some fields of a table of access according to the value of parameter. If this paramter is "true" I need to update. Table idInvoice price percentageTax1 tax1 percentageTax2 tax2 total Example values: idinvoice: 12300 price: 100 € percentageTax1: 10 % tax1= 10€ percentageTax2: 5 % tax2: 5€ total: 115 € (result: 100€+10€+5€) Ok. If the parameter on that I have commented before is "true" I must update the percentages and then update the total. I need to replace the "old" percentages by new percent. Ok I can do it in 3 queries: update invocies set percentageTax1=20,tax1=price *(percentageTax1/100) where idInvoice=@number and percentageTax1=10 update invocies set percentageTax2=7,tax2=price *(percentageTax2/100) where idInvoice=@number and percentageTax2=5 update invocies set total=price+tax1+tax2 where idInvoice=@number . But my question is: is there any an alternative to do this in 1 query?

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  • How can I change this method to get rid of the warning without anything changing?

    - by user3591323
    So this question:Warning-used as the name of the previous parameter rather than as part of the selector answers part of my problem, but I really don't want anything to change inside this method and I'm a bit confused on how this works. Here's the whole method: -(void) SetRightWrong:(sqzWord *)word: (int) rightWrong { if (self.mastered==nil) { self.mastered = [[NSMutableArray alloc]initWithCapacity:10]; } //if right change number right if (rightWrong == 1) { word.numberCorrect++; //if 3 right move to masterd list [self.onDeck removeObject:word]; if(word.numberCorrect >= 3 ) { [self.mastered addObject:word]; } else { //if not 3 right move to end of ondeck [self.onDeck addObject:word]; } } else if(rightWrong == 0) { //if wrong remove one from number right unless 0 NSUInteger i; i=[self.onDeck indexOfObject:word]; word = [self.onDeck objectAtIndex:i]; if (word.numberCorrect >0) { word.numberCorrect--; } } } The warning I am getting is: 'word' used as the name of the previous parameter than as part of the selector.

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  • How to assure applying order of function decorators in Python?

    - by Satoru.Logic
    Some decorators should only be used in the outermost layer. A decorator that augments the original function and add a configure parameter is one example. from functools import wraps def special_case(f): @wraps(f) def _(a, b, config_x=False): if config_x: print "Special case here" return return f(a, b) How can I avoid decorators like this getting decorated by another decorator? EDIT It is really disgusting to let everyone trying to apply a new decorator worry about the application order. So, is it possible to avoid this kind of situation? Is it possible to add a config option without introducing a new parameter?

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  • Is it possible to create a link that acts like a button and can carry out a function when clicked?

    - by Tim
    In PHP, I want to execute a function when a hyperlink is clicked. The only way I can think of doing this is by having the link attach a get parameter to the url when clicked and by doing an if statement that checks to see if that parameter exists and if so then have the function executed. But is there a way to do this like: <a href='#' onclick='<?php functionName(); ?>'> Obviously there are a million things wrong with this example but is it possible in any other way?

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  • Dynamic connection for LINQ to SQL DataContext

    - by Steve Clements
    If for some reason you need to specify a specific connection string for a DataContext, you can of course pass the connection string when you initialise you DataContext object.  A common scenario could be a dev/test/stage/live connection string, but in my case its for either a live or archive database.   I however want the connection string to be handled by the DataContext, there are probably lots of different reasons someone would want to do this…but here are mine. I want the same connection string for all instances of DataContext, but I don’t know what it is yet! I prefer the clean code and ease of not using a constructor parameter. The refactoring of using a constructor parameter could be a nightmare.   So my approach is to create a new partial class for the DataContext and handle empty constructor in there. First from within the LINQ to SQL designer I changed the connection property to None.  This will remove the empty constructor code from the auto generated designer.cs file. Right click on the .dbml file, click View Code and a file and class is created for you! You’ll see the new class created in solutions explorer and the file will open. We are going to be playing with constructors so you need to add the inheritance from System.Data.Linq.DataContext public partial class DataClasses1DataContext : System.Data.Linq.DataContext    {    }   Add the empty constructor and I have added a property that will get my connection string, you will have whatever logic you need to decide and get the connection string you require.  In my case I will be hitting a database, but I have omitted that code. public partial class DataClasses1DataContext : System.Data.Linq.DataContext {    // Connection String Keys - stored in web.config    static string LiveConnectionStringKey = "LiveConnectionString";    static string ArchiveConnectionStringKey = "ArchiveConnectionString";      protected static string ConnectionString    {       get       {          if (DoIWantToUseTheLiveConnection) {             return global::System.Configuration.ConfigurationManager.ConnectionStrings[LiveConnectionStringKey].ConnectionString;          }          else {             return global::System.Configuration.ConfigurationManager.ConnectionStrings[ArchiveConnectionStringKey].ConnectionString;          }       }    }      public DataClasses1DataContext() :       base(ConnectionString, mappingSource)    {       OnCreated();    } }   Now when I new up my DataContext, I can just leave the constructor empty and my partial class will decide which one i need to use. Nice, clean code that can be easily refractored and tested.   Share this post :

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  • Using jQuery to POST Form Data to an ASP.NET ASMX AJAX Web Service

    - by Rick Strahl
    The other day I got a question about how to call an ASP.NET ASMX Web Service or PageMethods with the POST data from a Web Form (or any HTML form for that matter). The idea is that you should be able to call an endpoint URL, send it regular urlencoded POST data and then use Request.Form[] to retrieve the posted data as needed. My first reaction was that you can’t do it, because ASP.NET ASMX AJAX services (as well as Page Methods and WCF REST AJAX Services) require that the content POSTed to the server is posted as JSON and sent with an application/json or application/x-javascript content type. IOW, you can’t directly call an ASP.NET AJAX service with regular urlencoded data. Note that there are other ways to accomplish this. You can use ASP.NET MVC and a custom route, an HTTP Handler or separate ASPX page, or even a WCF REST service that’s configured to use non-JSON inputs. However if you want to use an ASP.NET AJAX service (or Page Methods) with a little bit of setup work it’s actually quite easy to capture all the form variables on the client and ship them up to the server. The basic steps needed to make this happen are: Capture form variables into an array on the client with jQuery’s .serializeArray() function Use $.ajax() or my ServiceProxy class to make an AJAX call to the server to send this array On the server create a custom type that matches the .serializeArray() name/value structure Create extension methods on NameValue[] to easily extract form variables Create a [WebMethod] that accepts this name/value type as an array (NameValue[]) This seems like a lot of work but realize that steps 3 and 4 are a one time setup step that can be reused in your entire site or multiple applications. Let’s look at a short example that looks like this as a base form of fields to ship to the server: The HTML for this form looks something like this: <div id="divMessage" class="errordisplay" style="display: none"> </div> <div> <div class="label">Name:</div> <div><asp:TextBox runat="server" ID="txtName" /></div> </div> <div> <div class="label">Company:</div> <div><asp:TextBox runat="server" ID="txtCompany"/></div> </div> <div> <div class="label" ></div> <div> <asp:DropDownList runat="server" ID="lstAttending"> <asp:ListItem Text="Attending" Value="Attending"/> <asp:ListItem Text="Not Attending" Value="NotAttending" /> <asp:ListItem Text="Maybe Attending" Value="MaybeAttending" /> <asp:ListItem Text="Not Sure Yet" Value="NotSureYet" /> </asp:DropDownList> </div> </div> <div> <div class="label">Special Needs:<br /> <small>(check all that apply)</small></div> <div> <asp:ListBox runat="server" ID="lstSpecialNeeds" SelectionMode="Multiple"> <asp:ListItem Text="Vegitarian" Value="Vegitarian" /> <asp:ListItem Text="Vegan" Value="Vegan" /> <asp:ListItem Text="Kosher" Value="Kosher" /> <asp:ListItem Text="Special Access" Value="SpecialAccess" /> <asp:ListItem Text="No Binder" Value="NoBinder" /> </asp:ListBox> </div> </div> <div> <div class="label"></div> <div> <asp:CheckBox ID="chkAdditionalGuests" Text="Additional Guests" runat="server" /> </div> </div> <hr /> <input type="button" id="btnSubmit" value="Send Registration" /> The form includes a few different kinds of form fields including a multi-selection listbox to demonstrate retrieving multiple values. Setting up the Server Side [WebMethod] The [WebMethod] on the server we’re going to call is going to be very simple and just capture the content of these values and echo then back as a formatted HTML string. Obviously this is overly simplistic but it serves to demonstrate the simple point of capturing the POST data on the server in an AJAX callback. public class PageMethodsService : System.Web.Services.WebService { [WebMethod] public string SendRegistration(NameValue[] formVars) { StringBuilder sb = new StringBuilder(); sb.AppendFormat("Thank you {0}, <br/><br/>", HttpUtility.HtmlEncode(formVars.Form("txtName"))); sb.AppendLine("You've entered the following: <hr/>"); foreach (NameValue nv in formVars) { // strip out ASP.NET form vars like _ViewState/_EventValidation if (!nv.name.StartsWith("__")) { if (nv.name.StartsWith("txt") || nv.name.StartsWith("lst") || nv.name.StartsWith("chk")) sb.Append(nv.name.Substring(3)); else sb.Append(nv.name); sb.AppendLine(": " + HttpUtility.HtmlEncode(nv.value) + "<br/>"); } } sb.AppendLine("<hr/>"); string[] needs = formVars.FormMultiple("lstSpecialNeeds"); if (needs == null) sb.AppendLine("No Special Needs"); else { sb.AppendLine("Special Needs: <br/>"); foreach (string need in needs) { sb.AppendLine("&nbsp;&nbsp;" + need + "<br/>"); } } return sb.ToString(); } } The key feature of this method is that it receives a custom type called NameValue[] which is an array of NameValue objects that map the structure that the jQuery .serializeArray() function generates. There are two custom types involved in this: The actual NameValue type and a NameValueExtensions class that defines a couple of extension methods for the NameValue[] array type to allow for single (.Form()) and multiple (.FormMultiple()) value retrieval by name. The NameValue class is as simple as this and simply maps the structure of the array elements of .serializeArray(): public class NameValue { public string name { get; set; } public string value { get; set; } } The extension method class defines the .Form() and .FormMultiple() methods to allow easy retrieval of form variables from the returned array: /// <summary> /// Simple NameValue class that maps name and value /// properties that can be used with jQuery's /// $.serializeArray() function and JSON requests /// </summary> public static class NameValueExtensionMethods { /// <summary> /// Retrieves a single form variable from the list of /// form variables stored /// </summary> /// <param name="formVars"></param> /// <param name="name">formvar to retrieve</param> /// <returns>value or string.Empty if not found</returns> public static string Form(this NameValue[] formVars, string name) { var matches = formVars.Where(nv => nv.name.ToLower() == name.ToLower()).FirstOrDefault(); if (matches != null) return matches.value; return string.Empty; } /// <summary> /// Retrieves multiple selection form variables from the list of /// form variables stored. /// </summary> /// <param name="formVars"></param> /// <param name="name">The name of the form var to retrieve</param> /// <returns>values as string[] or null if no match is found</returns> public static string[] FormMultiple(this NameValue[] formVars, string name) { var matches = formVars.Where(nv => nv.name.ToLower() == name.ToLower()).Select(nv => nv.value).ToArray(); if (matches.Length == 0) return null; return matches; } } Using these extension methods it’s easy to retrieve individual values from the array: string name = formVars.Form("txtName"); or multiple values: string[] needs = formVars.FormMultiple("lstSpecialNeeds"); if (needs != null) { // do something with matches } Using these functions in the SendRegistration method it’s easy to retrieve a few form variables directly (txtName and the multiple selections of lstSpecialNeeds) or to iterate over the whole list of values. Of course this is an overly simple example – in typical app you’d probably want to validate the input data and save it to the database and then return some sort of confirmation or possibly an updated data list back to the client. Since this is a full AJAX service callback realize that you don’t have to return simple string values – you can return any of the supported result types (which are most serializable types) including complex hierarchical objects and arrays that make sense to your client code. POSTing Form Variables from the Client to the AJAX Service To call the AJAX service method on the client is straight forward and requires only use of little native jQuery plus JSON serialization functionality. To start add jQuery and the json2.js library to your page: <script src="Scripts/jquery.min.js" type="text/javascript"></script> <script src="Scripts/json2.js" type="text/javascript"></script> json2.js can be found here (be sure to remove the first line from the file): http://www.json.org/json2.js It’s required to handle JSON serialization for those browsers that don’t support it natively. With those script references in the document let’s hookup the button click handler and call the service: $(document).ready(function () { $("#btnSubmit").click(sendRegistration); }); function sendRegistration() { var arForm = $("#form1").serializeArray(); $.ajax({ url: "PageMethodsService.asmx/SendRegistration", type: "POST", contentType: "application/json", data: JSON.stringify({ formVars: arForm }), dataType: "json", success: function (result) { var jEl = $("#divMessage"); jEl.html(result.d).fadeIn(1000); setTimeout(function () { jEl.fadeOut(1000) }, 5000); }, error: function (xhr, status) { alert("An error occurred: " + status); } }); } The key feature in this code is the $("#form1").serializeArray();  call which serializes all the form fields of form1 into an array. Each form var is represented as an object with a name/value property. This array is then serialized into JSON with: JSON.stringify({ formVars: arForm }) The format for the parameter list in AJAX service calls is an object with one property for each parameter of the method. In this case its a single parameter called formVars and we’re assigning the array of form variables to it. The URL to call on the server is the name of the Service (or ASPX Page for Page Methods) plus the name of the method to call. On return the success callback receives the result from the AJAX callback which in this case is the formatted string which is simply assigned to an element in the form and displayed. Remember the result type is whatever the method returns – it doesn’t have to be a string. Note that ASP.NET AJAX and WCF REST return JSON data as a wrapped object so the result has a ‘d’ property that holds the actual response: jEl.html(result.d).fadeIn(1000); Slightly simpler: Using ServiceProxy.js If you want things slightly cleaner you can use the ServiceProxy.js class I’ve mentioned here before. The ServiceProxy class handles a few things for calling ASP.NET and WCF services more cleanly: Automatic JSON encoding Automatic fix up of ‘d’ wrapper property Automatic Date conversion on the client Simplified error handling Reusable and abstracted To add the service proxy add: <script src="Scripts/ServiceProxy.js" type="text/javascript"></script> and then change the code to this slightly simpler version: <script type="text/javascript"> proxy = new ServiceProxy("PageMethodsService.asmx/"); $(document).ready(function () { $("#btnSubmit").click(sendRegistration); }); function sendRegistration() { var arForm = $("#form1").serializeArray(); proxy.invoke("SendRegistration", { formVars: arForm }, function (result) { var jEl = $("#divMessage"); jEl.html(result).fadeIn(1000); setTimeout(function () { jEl.fadeOut(1000) }, 5000); }, function (error) { alert(error.message); } ); } The code is not very different but it makes the call as simple as specifying the method to call, the parameters to pass and the actions to take on success and error. No more remembering which content type and data types to use and manually serializing to JSON. This code also removes the “d” property processing in the response and provides more consistent error handling in that the call always returns an error object regardless of a server error or a communication error unlike the native $.ajax() call. Either approach works and both are pretty easy. The ServiceProxy really pays off if you use lots of service calls and especially if you need to deal with date values returned from the server  on the client. Summary Making Web Service calls and getting POST data to the server is not always the best option – ASP.NET and WCF AJAX services are meant to work with data in objects. However, in some situations it’s simply easier to POST all the captured form data to the server instead of mapping all properties from the input fields to some sort of message object first. For this approach the above POST mechanism is useful as it puts the parsing of the data on the server and leaves the client code lean and mean. It’s even easy to build a custom model binder on the server that can map the array values to properties on an object generically with some relatively simple Reflection code and without having to manually map form vars to properties and do string conversions. Keep in mind though that other approaches also abound. ASP.NET MVC makes it pretty easy to create custom routes to data and the built in model binder makes it very easy to deal with inbound form POST data in its original urlencoded format. The West Wind West Wind Web Toolkit also includes functionality for AJAX callbacks using plain POST values. All that’s needed is a Method parameter to query/form value to specify the method to be called on the server. After that the content type is completely optional and up to the consumer. It’d be nice if the ASP.NET AJAX Service and WCF AJAX Services weren’t so tightly bound to the content type so that you could more easily create open access service endpoints that can take advantage of urlencoded data that is everywhere in existing pages. It would make it much easier to create basic REST endpoints without complicated service configuration. Ah one can dream! In the meantime I hope this article has given you some ideas on how you can transfer POST data from the client to the server using JSON – it might be useful in other scenarios beyond ASP.NET AJAX services as well. Additional Resources ServiceProxy.js A small JavaScript library that wraps $.ajax() to call ASP.NET AJAX and WCF AJAX Services. Includes date parsing extensions to the JSON object, a global dataFilter for processing dates on all jQuery JSON requests, provides cleanup for the .NET wrapped message format and handles errors in a consistent fashion. Making jQuery Calls to WCF/ASMX with a ServiceProxy Client More information on calling ASMX and WCF AJAX services with jQuery and some more background on ServiceProxy.js. Note the implementation has slightly changed since the article was written. ww.jquery.js The West Wind West Wind Web Toolkit also includes ServiceProxy.js in the West Wind jQuery extension library. This version is slightly different and includes embedded json encoding/decoding based on json2.js.© Rick Strahl, West Wind Technologies, 2005-2010Posted in jQuery  ASP.NET  AJAX  

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