本文实例讲述了WinForm实现拦截窗体上各个部位的点击特效，是一个非常实用的技巧。分享给大家供大家参考。具体分析如下：
一般来说，windows窗体的标题栏无法直接通过一些默认的事件来控制，需要了解和WM_NCHITTEST相关的windows消息。
以下示例演示了最简单的效果片断：他会把客户区和标题栏的效果互换，比如无法按住标题栏拖动窗体而是改为了按住客户区拖动，并禁用了关闭按钮。 其中m.Result从-2到21都有定义，分别对应了整个窗体的各个部位，比如1代表客户区，8代表最小化按钮等等。
具体功能代码如下：
using System;
using System.Windows.Forms;
namespace WindowsApplication42
{
public partial class Form1 : Form
{
public Form1() { InitializeComponent(); this.Text = "双击左上角图标关闭窗体"; }
//拦击标题栏鼠标位置事件
const int WM_NCHITTEST = 0x84;
protected override void WndProc(ref Message m)
{
base.WndProc(ref m); if (m.Msg == WM_NCHITTEST)
{
switch (m.Result.ToInt32())
{
case 1://客户区
m.Result = new IntPtr(2); break;
case 2://标题栏
m.Result = new IntPtr(1); break;
case 20: m.Result = new IntPtr(0); break;
default: Console.WriteLine(m); break;
}
}
}
}
}
下面是各个常量的意义：从Delphi7 VCL中摘取：
{ WM_NCHITTEST and MOUSEHOOKSTRUCT Mouse Position Codes }
{$EXTERNALSYM HTERROR}
HTERROR = -2;
{$EXTERNALSYM HTTRANSPARENT}
HTTRANSPARENT = -1;
{$EXTERNALSYM HTNOWHERE}
HTNOWHERE = 0;
{$EXTERNALSYM HTCLIENT}
HTCLIENT = 1;
{$EXTERNALSYM HTCAPTION}
HTCAPTION = 2;
{$EXTERNALSYM HTSYSMENU}
HTSYSMENU = 3;
{$EXTERNALSYM HTGROWBOX}
HTGROWBOX = 4;
{$EXTERNALSYM HTSIZE}
HTSIZE = HTGROWBOX;
{$EXTERNALSYM HTMENU}
HTMENU = 5;
{$EXTERNALSYM HTHSCROLL}
HTHSCROLL = 6;
{$EXTERNALSYM HTVSCROLL}
HTVSCROLL = 7;
{$EXTERNALSYM HTMINBUTTON}
HTMINBUTTON = 8;
{$EXTERNALSYM HTMAXBUTTON}
HTMAXBUTTON = 9;
{$EXTERNALSYM HTLEFT}
HTLEFT = 10;
{$EXTERNALSYM HTRIGHT}
HTRIGHT = 11;
{$EXTERNALSYM HTTOP}
HTTOP = 12;
{$EXTERNALSYM HTTOPLEFT}
HTTOPLEFT = 13;
{$EXTERNALSYM HTTOPRIGHT}
HTTOPRIGHT = 14;
{$EXTERNALSYM HTBOTTOM}
HTBOTTOM = 15;
{$EXTERNALSYM HTBOTTOMLEFT}
HTBOTTOMLEFT = 16;
{$EXTERNALSYM HTBOTTOMRIGHT}
HTBOTTOMRIGHT = 17;
{$EXTERNALSYM HTBORDER}
HTBORDER = 18;
{$EXTERNALSYM HTREDUCE}
HTREDUCE = HTMINBUTTON;
{$EXTERNALSYM HTZOOM}
HTZOOM = HTMAXBUTTON;
{$EXTERNALSYM HTSIZEFIRST}
HTSIZEFIRST = HTLEFT;
{$EXTERNALSYM HTSIZELAST}
HTSIZELAST = HTBOTTOMRIGHT;
{$EXTERNALSYM HTOBJECT}
HTOBJECT = 19;
{$EXTERNALSYM HTCLOSE}
HTCLOSE = 20;
{$EXTERNALSYM HTHELP}
HTHELP = 21;
希望本文所述对大家的C#程序设计有所帮助。
