Calling radalert from codebehind (all versions of RadWindow)

 

Article information
Article relates to	all versions of RadWindow
Created by	Georgi, Telerik
Last modified	January 5th, 2012
Last modified by	Marin, Telerik

HOW-TO
Call radalert() from codebehind.






NOTE: Since Q1 2011 (2011.1.315) the RadWindowManager offers three built-in server-side methods that allow you to call a RadAlert, RadConfirm and RadPrompt from the server. More information about their syntax is available in this online demo which also shows them in action. 



When calling the radalert() function server-side in ASP.NET AJAX environment, you should keep in mind that the page lifecycle is different. RadControls for ASP.NET AJAX, being MS AJAX objects, are rendered after page is loaded (e.g. after window.onload is fired). Therefore executing code in the window.onload event doesn't ensure that the RadWindowManager is already rendered on the page and you need to add a Sys.Application.Load handler. We however, must make sure that the code is executed only once and then removed from the Load handler - otherwise it will be called after every Ajax callback. One way to do this is to use the following logic :


The attached examples show how to do this in the following scenarios:

1. Calling radalert() on postback. In this case you can use the RegisterStartupScript() server method if you are using ASP.NET AJAX controls (used in the example).
   
    ASPX
   

   <form id="form1" runat="server">

   <asp:ScriptManager ID="ScriptManager1" runat="server" />

   <telerik:RadWindowManager ID="RadWindowManager1" runat="server">

   </telerik:RadWindowManager>

   <asp:Button ID="Button1" Text="Postback and show RadAlert" runat="server"  OnClick="Button1_Click" />

   </form>

   
   C#
   

   protected void Button1_Click(object sender, EventArgs e)

   {

   string radalertscript = "<script language='javascript'>function f(){radalert('Welcome to RadWindow <b>Prometheus</b>!', 330, 210); Sys.Application.remove_load(f);}; Sys.Application.add_load(f);</script>";

   Page.ClientScript.RegisterStartupScript(this.GetType(), "radalert", radalertscript);

   }

   
   VB.NET
   

   Protected Sub Button1_Click(sender As Object, e As EventArgs)

   Dim radalertscript As String = "<script language='javascript'>function f(){radalert('Welcome to RadWindow <b>Prometheus</b>!', 330, 210); Sys.Application.remove_load(f);}; Sys.Application.add_load(f);</script>"

   Page.ClientScript.RegisterStartupScript(Me.[GetType](), "radalert", radalertscript)

   End Sub

2. Calling radalert() on ASP.NET AJAX callback: Use the RegisterStartupScript() server method of the ScriptManager to achieve the desired behavior:
   
    ASPX
   

   <form id="form1" runat="server">

   <asp:ScriptManager ID="ScriptManager1" runat="server">

   </asp:ScriptManager>

   <telerik:RadWindowManager ID="RadWindowManager1" runat="server">

   </telerik:RadWindowManager>

   <asp:UpdatePanel ID="UpdatePanel1" runat="server">

   <ContentTemplate>

   <asp:Button ID="Button1" Text="CallBack and show RadAlert" runat="server" OnClick="Button1_Click" />

   </ContentTemplate>

   </asp:UpdatePanel>

   </form>

   
   C#
   

   protected void Button1_Click(object sender, EventArgs e)

   {

   string scriptstring = "radalert('Welcome to Rad<b>window</b>!', 330, 210);";

   ScriptManager.RegisterStartupScript(this, this.GetType(), "radalert", scriptstring, true);

   }

   
   VB.NET
   

   Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)

   Dim scriptstring As String = "radalert('Welcome to Rad<b>window</b>!', 330, 210);"

   ScriptManager.RegisterStartupScript(Me, Me.[GetType](), "radalert", scriptstring, True)

   End Sub

3. Calling radalert on RadAjax callback: You can use the ResponseScripts collection of RadAjaxManager for this purpose:
   
   ASPX
   

   <form id="form1" runat="server">

   <asp:ScriptManager ID="ScriptManager1" runat="server">

   </asp:ScriptManager>

   <telerik:RadWindowManager ID="RadWindowManager1" runat="server">

   </telerik:RadWindowManager>

   <telerik:RadAjaxManager ID="RadAjaxManager1" runat="server">

   <AjaxSettings>

   <telerik:AjaxSetting AjaxControlID="Button1">

   <UpdatedControls>

   <telerik:AjaxUpdatedControl ControlID="RadWindowManager1" />

   </UpdatedControls>

   </telerik:AjaxSetting>

   </AjaxSettings>

   </telerik:RadAjaxManager>

   <asp:Button ID="Button1" Text="Callback and show RadAlert" runat="server" OnClick="Button1_Click" />

   </form>

   
   C#
   

   protected void Button1_Click(object sender, EventArgs e)

   {

   RadAjaxManager1.ResponseScripts.Add(@"radalert('Welcome to RadWindow <b>Prometheus</b>!', 330, 210);");

   }

   
   VB.NET
   

   Protected Sub Button1_Click(sender As Object, e As EventArgs)

   RadAjaxManager1.ResponseScripts.Add("radalert('Welcome to RadWindow <b>Prometheus</b>!', 330, 210);")

   End Sub

The main idea in calling radalert() server-side when using the RadControls for ASP.NET RadWindowManager stays the same excluding Sys.Application.load event, because this suite is not built upon the MS AJAX Framework.

The attached examples show how to do this in the following scenarios:

1. Calling radalert() on postback. In this case you can use the RegisterStartupScript() server method if you are using ASP.NET v2.x (used in the example).
   ASPX
   

   <form id="form1" runat="server">

   <radW:RadWindowManager ID="RadWindowManager1" runat="server">

   </radW:RadWindowManager>

   <asp:Button ID="Button1" Text="Postback and show RadAlert" runat="server" OnClick="Button1_Click" />&nbsp;

   </form>

   
   C#
   

   protected void Button1_Click(object sender, EventArgs e)

   {

   string radalertscript = "<script language='javascript'> window.onload = function(){radalert('Welcome to Rad<b>window</b>!', 330, 210);}</script>";

   Page.ClientScript.RegisterStartupScript(this.GetType(), "radalert", radalertscript);

   }

   
   VB.NET
   

   Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

   Dim radalertscript As String = "<script language='javascript'> window.onload = function(){radalert('Welcome to Rad<b>window</b>!', 330, 210);}</script>"

   Page.ClientScript.RegisterStartupScript(Me.[GetType](), "radalert", radalertscript)

   End Sub

   
   
   
2. Calling radalert() on ASP.NET AJAX callback: Use the RegisterStartupScript() server method of the ScriptManager to achieve the desired behavior:
   ASPX
   

   <asp:ScriptManager ID="ScriptManager1" runat="server">

   </asp:ScriptManager>

   <radW:RadWindowManager ID="RadWindowManager1" runat="server">

   </radW:RadWindowManager>

   <asp:UpdatePanel ID="UpdatePanel1" runat="server">

   <ContentTemplate>

   <asp:Button ID="Button1" Text="CallBack and show RadAlert" runat="server" OnClick="Button1_Click" />

   </ContentTemplate>

   </asp:UpdatePanel>

   
   C#
   

   protected void Button1_Click(object sender, EventArgs e)

   {

   string scriptstring = "radalert('Welcome to Rad<b>window</b>!', 330, 210);";

   ScriptManager.RegisterStartupScript(this, this.GetType(), "radalert", scriptstring, true);

   }

   
   VB.NET
   

   Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

   Dim scriptstring As String = "radalert('Welcome to Rad<b>window</b>!', 330, 210);"

   ScriptManager.RegisterStartupScript(Me, Me.[GetType](), "radalert", scriptstring, True)

   End Sub

3. Calling radalert on RadAjax callback: You can use the ResponseScripts collection of RadAjaxManager for this purpose:
   ASPX
   
   

   <form id="form1" runat="server">

   <radW:RadWindowManager ID="RadWindowManager1" runat="server">

   </radW:RadWindowManager>

   <radA:RadAjaxManager ID="RadAjaxManager1" runat="server">

   <AjaxSettings>

   <radA:AjaxSetting AjaxControlID="Button1">

   <UpdatedControls>

   <radA:AjaxUpdatedControl ControlID="RadWindowManager1" />

   </UpdatedControls>

   </radA:AjaxSetting>

   </AjaxSettings>

   </radA:RadAjaxManager>

   <asp:Button ID="Button1" Text="Callback and show RadAlert" runat="server" OnClick="Button1_Click" />

   </form>

   
    
   C#
   

   protected void Button1_Click(object sender, EventArgs e)

   {

   RadAjaxManager1.ResponseScripts.Add("radalert('Welcome to Rad<b>window</b>!', 330, 210);");

   }

   
   VB.NET
   

   Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

   RadAjaxManager1.ResponseScripts.Add("radalert('Welcome to Rad<b>window</b>!', 330, 210);")

   End Sub

 
Depending on the case, your exact scenario might differ from the ones used in the examples - in this case you can modify the code to fit your requirements. The main idea stays the same:

1. Make sure that the JavaScript is output on the page.
2. Make sure that the RadWindowManager is rendered on the page before you execute the JavaScript.