摘自:http://stackoverflow.com/questions/4615940/how-can-i-customize-the-system-menu-of-a-windows-form
在单击窗体左上角图标,或标题栏右击时,显示自定义菜单
Imports System.Windows.Forms
Imports System.Runtime.InteropServices
Public Class CustomForm
Inherits Form
' P/Invoke constants
Private Const WM_SYSCOMMAND As Integer = &H112
Private Const MF_STRING As Integer = &H0
Private Const MF_SEPARATOR As Integer = &H800
' P/Invoke declarations
<DllImport("user32.dll", CharSet:=CharSet.Auto, SetLastError:=True)>
Private Shared Function GetSystemMenu(hWnd As IntPtr, bRevert As Boolean) As IntPtr
End Function
<DllImport("user32.dll", CharSet:=CharSet.Auto, SetLastError:=True)>
Private Shared Function AppendMenu(hMenu As IntPtr, uFlags As Integer, uIDNewItem As Integer, lpNewItem As String) As Boolean
End Function
<DllImport("user32.dll", CharSet:=CharSet.Auto, SetLastError:=True)>
Private Shared Function InsertMenu(hMenu As IntPtr, uPosition As Integer, uFlags As Integer, uIDNewItem As Integer, lpNewItem As String) As Boolean
End Function
' ID for the About item on the system menu
Private SYSMENU_ABOUT_ID As Integer = &H1
Public Sub New()
End Sub
Protected Overrides Sub OnHandleCreated(e As EventArgs)
MyBase.OnHandleCreated(e)
' Get a handle to a copy of this form's system (window) menu
Dim hSysMenu As IntPtr = GetSystemMenu(Me.Handle, False)
' Add a separator
AppendMenu(hSysMenu, MF_SEPARATOR, 0, String.Empty)
' Add the About menu item
AppendMenu(hSysMenu, MF_STRING, SYSMENU_ABOUT_ID, "&About…")
End Sub
Protected Overrides Sub WndProc(ByRef m As Message)
MyBase.WndProc(m)
' Test if the About item was selected from the system menu
If m.Msg = WM_SYSCOMMAND AndAlso m.WParam.ToInt32 = SYSMENU_ABOUT_ID Then
MessageBox.Show("Custom About Dialog")
End If
End Sub
End Class