C#屏蔽ComboBox系统右键菜单介绍(通过API拦截消息)

来源：互联网发布：量子技术知乎编辑：程序博客网时间：2024/06/05 19:56

C#屏蔽ComboBox系统右键菜单代码如下：

using System.Runtime.InteropServices; [DllImport("user32.dll")]public static extern IntPtr GetWindow(IntPtr hWnd, uint uCmd);public const uint GW_CHILD= 5; private delegate IntPtr WndProcCallBack(IntPtr hwnd, int Msg,     IntPtr wParam, IntPtr lParam); [DllImport("user32.dll")]private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);[DllImport("user32.dll")]private static extern int GetWindowLong(IntPtr hWnd, int nIndex);[DllImport("User32.dll")]private static extern IntPtr CallWindowProc(IntPtr lpPrevWndFunc,     IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);private int GWL_WNDPROC= -4;private static IntPtr prevWndFunc;private IntPtr newWndProc(IntPtr hWnd, int iMsg, IntPtr wParam, IntPtr lParam){    const int WM_CONTEXTMENU = 0x007B;    switch (iMsg)    {        case WM_CONTEXTMENU:            return IntPtr.Zero;    }    return CallWindowProc(prevWndFunc, hWnd, iMsg, wParam, lParam);}private IntPtr comboBoxEdit;private WndProcCallBack wndProcCallBack;private void Form1_Load(object sender, EventArgs e){    comboBoxEdit = GetWindow(comboBox1.Handle, GW_CHILD);    prevWndFunc = new IntPtr(GetWindowLong(comboBoxEdit, GWL_WNDPROC));    wndProcCallBack = new WndProcCallBack(newWndProc);    SetWindowLong(comboBoxEdit, GWL_WNDPROC,        (int)Marshal.GetFunctionPointerForDelegate(wndProcCallBack));}

 
C#创建右键菜单
范例说明:本范例讲解如何创建右键菜单，重点请注意菜单控件ContextMenuStrip的使用.
关键步骤:
1.创建一个新的Windows工程。
2.把ContextMenuStrip控件拖放到设计界面上,Name属性设置为cmMenu.
3.单击ContextMenuStrip控件的Type Here文本区域，可以输入菜单项的名称,如&new,然后回车.
4.添加RichTextBox控件，设置Name属性为"rchShow".
设置Form和RichTextBox的ContextMenuStript属性为“cmMenu”。
7.双击ContextMenuStrip控件的菜单项，添加Open事件。
/// <summary>
/// 右键菜单Open的处理事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void miOpen_Click(object sender, EventArgs e)
{
OpenFileDialog dlgOpen = new OpenFileDialog();
dlgOpen.Filter = "文本文件(*.txt)|*.txt";
if (dlgOpen.ShowDialog() == DialogResult.OK)
{
this.rchShow.LoadFile(dlgOpen.FileName,RichTextBoxStreamType.PlainText);
}
}
 
private void Form1_Load(object sender, EventArgs e)
{
ContextMenuStrip cms = new ContextMenuStrip();
cms.Items.Add("第一个");
cms.Items.Add("第二个");
this.ContextMenuStrip = cms;
}