แก้ไข

แชร์ผ่าน


FormViewDeletedEventArgs.ExceptionHandled Property

Definition

Gets or sets a value indicating whether an exception that was raised during the delete operation was handled in the event handler.

public:
 property bool ExceptionHandled { bool get(); void set(bool value); };
public bool ExceptionHandled { get; set; }
member this.ExceptionHandled : bool with get, set
Public Property ExceptionHandled As Boolean

Property Value

true if the exception was handled in the event handler; otherwise, false. The default is false.

Examples

The following example demonstrates how to use the ExceptionHandled property to indicate that the exception was handled in the event handler.


<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void EmployeeFormView_ItemDeleted(Object sender, FormViewDeletedEventArgs e)
  {
    // Use the Exception property to determine whether an exception
    // occurred during the delete operation.
    if (e.Exception == null)
    {
      // Use the AffectedRows property to determine whether the
      // record was deleted. Sometimes an error might occur that 
      // does not raise an exception, but prevents the delete
      // operation from completing.
      if (e.AffectedRows == 1)
      {
        MessageLabel.Text = "Record deleted successfully.";
      }
      else
      {
        MessageLabel.Text = "An error occurred during the delete operation.";
      }
    }
    else
    {
      // Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message;
      
      // Use the ExceptionHandled property to indicate that the 
      // exception has already been handled.
      e.ExceptionHandled = true;
    }
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormViewDeletedEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewDeletedEventArgs Example</h3>
                       
      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        onitemdeleted="EmployeeFormView_ItemDeleted"  
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td>
                <asp:image id="EmployeeImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td>
                <h3><%# Eval("FirstName") %> <%# Eval("LastName") %></h3>      
                <%# Eval("Title") %>        
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="DeleteButton"
                  text="Delete Record"
                  commandname="Delete"
                  runat="server" />
              </td>
            </tr>
          </table>
        
        </itemtemplate>         
                  
      </asp:formview>
      
      <asp:label id="MessageLabel"
        forecolor="Red"
        runat="server"/>
          
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        deletecommand="Delete [Employees] Where [EmployeeID]=@EmployeeID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

<%@ Page language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub EmployeeFormView_ItemDeleted(ByVal sender As Object, ByVal e As FormViewDeletedEventArgs) Handles EmployeeFormView.ItemDeleted
  
    ' Use the Exception property to determine whether an exception
    ' occurred during the delete operation.
    If e.Exception Is Nothing Then
    
      ' Use the AffectedRows property to determine whether the
      ' record was deleted. Sometimes an error might occur that 
      ' does not raise an exception, but prevents the delete
      ' operation from completing.
      If e.AffectedRows = 1 Then
      
        MessageLabel.Text = "Record deleted successfully."
      
      Else
              
        MessageLabel.Text = "An error occurred during the delete operation."
      
      End If
    
    Else
    
      ' Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message
      
      ' Use the ExceptionHandled property to indicate that the 
      ' exception has already been handled.
      e.ExceptionHandled = True
      
    End If
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormViewDeletedEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewDeletedEventArgs Example</h3>
                       
      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td>
                <asp:image id="EmployeeImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td>
                <h3><%# Eval("FirstName") %> <%# Eval("LastName") %></h3>      
                <%# Eval("Title") %>        
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="DeleteButton"
                  text="Delete Record"
                  commandname="Delete"
                  runat="server" />
              </td>
            </tr>
          </table>
        
        </itemtemplate>         
                  
      </asp:formview>
      
      <asp:label id="MessageLabel"
        forecolor="Red"
        runat="server"/>
          
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        deletecommand="Delete [Employees] Where [EmployeeID]=@EmployeeID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

Remarks

When an exception is raised during the delete operation, use the ExceptionHandled property to indicate whether the exception was handled in the event handler. When this property is set to true, the exception is considered handled and is not re-thrown. If this property is set to false, the FormView control re-throws the exception. To determine which exception was raised, use the Exception property.

Applies to

See also