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TemplateControl.OnError(EventArgs) Method

  • Reference

Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Raises the Error event.

protected:
 virtual void OnError(EventArgs ^ e);
protected virtual void OnError (EventArgs e);
abstract member OnError : EventArgs -> unit
override this.OnError : EventArgs -> unit
Protected Overridable Sub OnError (e As EventArgs)

Parameters

e
EventArgs

An EventArgs that contains the event data.

Examples

The following code example demonstrates a possible way to use of the OnError method. It creates a string with some arguments that are not valid, which leads to an exception. Because the TemplateControl class is an abstract class, this code example was written using the Page class, which is derived from the TemplateControl class.

<%@ Page language="VB" %>  
 <html>  
  <head>  
  <script language="VB" runat="server">  
  Sub Page_Load(sender as object, e as System.EventArgs)  
  AddHandler Page.Error, AddressOf Error_Handler  
  try  
  Dim myString as string = "Hello"  
  'An exception is raised because the length of 'myString' is less than '6'.  
  Dim mySubString as string= myString.Substring(0,6)  
  catch e1 As Exception  
  OnError (EventArgs.Empty)  
  End try  
  End Sub  
  Sub Error_Handler(sender as object,e as System.EventArgs)  
  Response.Write("<br><b>An Error was raised</b>")  
  End Sub  
  </script>  
  </head>  
 </html>  

<%@ Page language="c#" %>  
 <html>  
  <head>  
  <script language="C#" runat="server">  
  void Page_Load(object sender, System.EventArgs e)  
  {  
  Page.Error += new System.EventHandler(Error_Handler);  
  try  
  {  
  string myString = "Hello";  
  // An exception is raised because the length of 'myString' is less than '6'.  
  string mySubString = myString.Substring(0,6);  
  }  
  catch(Exception)  
  {  
  OnError(EventArgs.Empty);  
  }  
  }  
  void Error_Handler(object sender,System.EventArgs e)  
  {  
  Response.Write("<br><b>An Error was raised</b>");  
  }  
  </script>  
  </head>  
 </html>

Applies to