ToolStripDropDown.KeyDown 事件

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

在 ToolStripDropDown 具有焦点的情况下按下某个键并保持时发生。

public:
 event System::Windows::Forms::KeyEventHandler ^ KeyDown;

[System.ComponentModel.Browsable(false)]
public event System.Windows.Forms.KeyEventHandler? KeyDown;

[<System.ComponentModel.Browsable(false)>]
member this.KeyDown : System.Windows.Forms.KeyEventHandler 

Public Custom Event KeyDown As KeyEventHandler 

事件类型

KeyEventHandler

属性

BrowsableAttribute

示例

下面的代码示例演示了此成员的用法。 在此示例中，事件处理程序报告事件的发生情况 KeyDown 。 此报告可帮助你了解事件发生的时间，并可以帮助你进行调试。 若要报告多个事件或频繁发生的事件，请考虑将 MessageBox.ShowConsole.WriteLine 消息替换为 或将消息追加到多行 TextBox。

若要运行示例代码，请将其粘贴到包含名为 ToolStripDropDown1的类型的ToolStripDropDown实例的项目中。 然后，确保事件处理程序与 KeyDown 事件相关联。

private void ToolStripDropDown1_KeyDown(Object sender, KeyEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "Alt", e.Alt );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Control", e.Control );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Handled", e.Handled );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "KeyCode", e.KeyCode );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "KeyValue", e.KeyValue );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "KeyData", e.KeyData );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Modifiers", e.Modifiers );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Shift", e.Shift );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "SuppressKeyPress", e.SuppressKeyPress );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "KeyDown Event" );
}

Private Sub ToolStripDropDown1_KeyDown(sender as Object, e as KeyEventArgs) _ 
     Handles ToolStripDropDown1.KeyDown

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "Alt", e.Alt)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Control", e.Control)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Handled", e.Handled)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "KeyCode", e.KeyCode)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "KeyValue", e.KeyValue)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "KeyData", e.KeyData)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Modifiers", e.Modifiers)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Shift", e.Shift)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "SuppressKeyPress", e.SuppressKeyPress)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"KeyDown Event")

End Sub

注解

有关处理事件的详细信息，请参阅 处理和引发事件。