ToolStripDropDown.Closing Ereignis

Referenz

Definition

Namespace:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Tritt kurz vor dem Schließen des ToolStripDropDown-Steuerelements auf.

public:
 event System::Windows::Forms::ToolStripDropDownClosingEventHandler ^ Closing;

public event System.Windows.Forms.ToolStripDropDownClosingEventHandler Closing;

public event System.Windows.Forms.ToolStripDropDownClosingEventHandler? Closing;

member this.Closing : System.Windows.Forms.ToolStripDropDownClosingEventHandler

Public Custom Event Closing As ToolStripDropDownClosingEventHandler

Ereignistyp

ToolStripDropDownClosingEventHandler

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie ein ToolStripDropDown Steuerelement selektiv geschlossen wird, indem das Closing -Ereignis behandelt wird.

// This method handles the Closing event. The ToolStripDropDown
// control is not allowed to close unless the Done menu item
// is clicked or the Close method is called explicitly.
// The Done menu item is enabled only after both of the other
// menu items have been selected.
private void contextMenuStrip_Closing(
    object sender, 
    ToolStripDropDownClosingEventArgs e)
{
    if (e.CloseReason != ToolStripDropDownCloseReason.CloseCalled)
    {
        if (subItem1ToolStripMenuItem.Checked &&
            subItem2ToolStripMenuItem.Checked &&
            doneToolStripMenuItem.Enabled)
        {
            // Reset the state of menu items.
            subItem1ToolStripMenuItem.Checked = false;
            subItem2ToolStripMenuItem.Checked = false;
            doneToolStripMenuItem.Enabled = false;

            // Allow the ToolStripDropDown to close.
            // Don't cancel the Close operation.
            e.Cancel = false;
        }
        else
        {
            // Cancel the Close operation to keep the menu open.
            e.Cancel = true;
            this.toolStripStatusLabel1.Text = "Close canceled";
        }
    }
}

' This method handles the Closing event. The ToolStripDropDown
' control is not allowed to close unless the Done menu item
' is clicked or the Close method is called explicitly.
' The Done menu item is enabled only after both of the other
' menu items have been selected.
Private Sub contextMenuStrip_Closing(sender As Object, e As ToolStripDropDownClosingEventArgs) Handles contextMenuStrip1.Closing
   If e.CloseReason <> ToolStripDropDownCloseReason.CloseCalled Then
      If subItem1ToolStripMenuItem.Checked AndAlso subItem2ToolStripMenuItem.Checked AndAlso doneToolStripMenuItem.Enabled Then
         ' Reset the state of menu items.
         subItem1ToolStripMenuItem.Checked = False
         subItem2ToolStripMenuItem.Checked = False
         doneToolStripMenuItem.Enabled = False
         
         ' Allow the ToolStripDropDown to close.
         ' Don't cancel the Close operation.
         e.Cancel = False
      Else
         ' Cancel the Close operation to keep the menu open.
         e.Cancel = True
         Me.toolStripStatusLabel1.Text = "Close canceled"
      End If
   End If
 End Sub

Hinweise

Weitere Informationen zur Behandlung von Ereignissen finden Sie unter behandeln und Auslösen von Ereignissen.

Gilt für:

Freigeben über