CheckedListBox.ItemCheck CheckedListBox.ItemCheck CheckedListBox.ItemCheck CheckedListBox.ItemCheck Event

定义

当某项的选中状态更改时发生。Occurs when the checked state of an item changes.

public:
 event System::Windows::Forms::ItemCheckEventHandler ^ ItemCheck;
public event System.Windows.Forms.ItemCheckEventHandler ItemCheck;
member this.ItemCheck : System.Windows.Forms.ItemCheckEventHandler 
Public Custom Event ItemCheck As ItemCheckEventHandler 

示例

下面的代码示例演示如何使用此成员。The following code example demonstrates the use of this member. 在此示例中, 事件处理程序报告ItemCheck事件的发生。In the example, an event handler reports on the occurrence of the ItemCheck event. 此报表可帮助你了解何时发生事件, 并可帮助你进行调试。This report helps you to learn when the event occurs and can assist you in debugging. 若要报告多个事件或频繁发生的事件, 请考虑MessageBox.ShowConsole.WriteLine消息替换为多行或将TextBox其追加到多行。To report on multiple events or on events that occur frequently, consider replacing MessageBox.Show with Console.WriteLine or appending the message to a multiline TextBox.

若要运行示例代码, 请将其粘贴到包含名为CheckedListBox CheckedListBox1的类型的实例的项目中。To run the example code, paste it into a project that contains an instance of type CheckedListBox named CheckedListBox1. 然后, 确保事件处理程序与ItemCheck事件相关联。Then ensure that the event handler is associated with the ItemCheck event.

private void CheckedListBox1_ItemCheck(Object sender, ItemCheckEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "Index", e.Index );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "NewValue", e.NewValue );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "CurrentValue", e.CurrentValue );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "ItemCheck Event" );
}
Private Sub CheckedListBox1_ItemCheck(sender as Object, e as ItemCheckEventArgs) _ 
     Handles CheckedListBox1.ItemCheck

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "Index", e.Index)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "NewValue", e.NewValue)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "CurrentValue", e.CurrentValue)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"ItemCheck Event")

End Sub

注解

ItemCheck事件发生之后,检查状态才会更新。The check state is not updated until after the ItemCheck event occurs.

适用于