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MenuItem.Popup Event

Definition

Occurs before a menu item's list of menu items is displayed.

C#
public event EventHandler Popup;

Event Type

Examples

The following code example demonstrates how to use the Popup event to determine whether MenuItem objects that provide support for cut, copy, and delete operations are enabled before the menu they are displayed in is shown. The example determines if textBox1, a TextBox control on the form, is enabled, has input focus, and has text selected before enabling the MenuItem objects. This example requires that three MenuItem objects are created named menuCut, menuCopy, and menuDelete have been created.

C#
private void PopupMyMenu(object sender, System.EventArgs e)
{
   if (!textBox1.Enabled || !textBox1.Focused ||
      textBox1.SelectedText.Length == 0)
   {
      menuCut.Enabled = false;
      menuCopy.Enabled = false;
      menuDelete.Enabled = false;
   }
   else
   {
      menuCut.Enabled = true;
      menuCopy.Enabled = true;
      menuDelete.Enabled = true;
   }
}

Remarks

This event only occurs when a menu item has submenu items to display. You can use this event handler to add, remove, enable, disable, check, or uncheck menu items based on the state of your application before they are displayed. For more information about handling events, see Handling and Raising Events.

Applies to

Продукт Версии
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
Windows Desktop 3.0, 10