TemplateControl.OnError(EventArgs) 方法

  • 參考

定義

命名空間:
System.Web.UI
組件:
System.Web.dll

引發 Error 事件。

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)

參數

e
EventArgs

包含事件資料的 EventArgs。

範例

下列程式碼範例示範使用 OnError 方法的可能方式。 它會建立字串，其中包含一些不正確引數，這會導致例外狀況。 因為類別 TemplateControl 是抽象類別，所以此程式碼範例是使用 Page 衍生自 類別的 TemplateControl 類別所撰寫。

<%@ 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>

適用於