ListView.BeforeLabelEdit ListView.BeforeLabelEdit ListView.BeforeLabelEdit ListView.BeforeLabelEdit Event

定义

当用户开始编辑项的标签时发生。Occurs when the user starts editing the label of an item.

public:
 event System::Windows::Forms::LabelEditEventHandler ^ BeforeLabelEdit;
public event System.Windows.Forms.LabelEditEventHandler BeforeLabelEdit;
member this.BeforeLabelEdit : System.Windows.Forms.LabelEditEventHandler 
Public Custom Event BeforeLabelEdit As LabelEditEventHandler 

示例

下面的代码示例演示如何处理BeforeLabelEdit事件以及如何LabelEditEventArgs.Item使用和LabelEditEventArgs.CancelEdit属性。The following code example demonstrates handling the BeforeLabelEdit event and using the LabelEditEventArgs.Item and LabelEditEventArgs.CancelEdit properties. 若要运行该示例,请将以下代码粘贴到包含ListView名为ListView1的控件的窗体中,其中至少填充了三项。To run the example, paste the following code into a form that contains a ListView control named ListView1 and populated with at least three items. 确保该示例中的事件处理程序与事件相关联。Ensure the event handler in the example is associated with its event.

void ListView1_BeforeLabelEdit( Object^ sender,
   System::Windows::Forms::LabelEditEventArgs^ e )
{
   // Allow all but the first two items of the list to 
   // be modified by the user.
   if ( e->Item < 2 )
   {
      e->CancelEdit = true;
   }
}
private void ListView1_BeforeLabelEdit(object sender, 
	System.Windows.Forms.LabelEditEventArgs e)
{
	// Allow all but the first two items of the list to 
	// be modified by the user.
	if (e.Item<2)
	{
		e.CancelEdit = true;
	}
}

Private Sub ListView1_BeforeLabelEdit(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.LabelEditEventArgs) _
    Handles ListView1.BeforeLabelEdit

    ' Allow all but the first two items of the list to be modified by
    ' the user.
    If (e.Item < 2) Then
        e.CancelEdit = True
    End If
End Sub

注解

BeforeLabelEdit用户开始修改项的文本时发生该事件。The BeforeLabelEdit event occurs when the user starts modifying the text for an item. 如果事件处理程序取消此事件,则用户无法编辑文本。If the event handler cancels this event, the user cannot edit the text. 你可以使用此事件来阻止用户编辑ListView控件中的特定项。You can use this event to prevent the user from editing specific items in the ListView control. 如果将LabelEdit ListView控件的属性设置为falseBeforeLabelEdit则不会引发事件; 将自动拒绝所有用户尝试编辑项标签。If the LabelEdit property of the ListView control is set to false, the BeforeLabelEdit event is not raised; all user attempts to edit item labels are automatically rejected.

有关处理事件的详细信息, 请参阅处理和引发事件For more information about handling events, see Handling and Raising Events.

适用于

另请参阅