把窗体的FormBorderStyle设为FormBorderStyle.None
using System.Runtime.InteropServices;
private const uint WS_EX_LAYERED = 0x80000;
private const int WS_EX_TRANSPARENT = 0x20;
private const int GWL_STYLE = (-16);
private const int GWL_EXSTYLE = (-20);
private const int LWA_ALPHA = 0x2;
[DllImport("user32", EntryPoint = "SetWindowLong")]
private static extern uint SetWindowLong(
IntPtr hwnd,
int nIndex,
uint dwNewLong
);
[DllImport("user32", EntryPoint = "GetWindowLong")]
private static extern uint GetWindowLong(
IntPtr hwnd,
int nIndex
);
[DllImport("user32", EntryPoint = "SetLayeredWindowAttributes")]
private static extern int SetLayeredWindowAttributes(
IntPtr hwnd,
int crKey,
int bAlpha,
int dwFlags
);
///
/// 使窗口有鼠标穿透功能
///
public void CanPenetrate()
{
uint intExTemp = GetWindowLong(this.Handle, GWL_EXSTYLE);
uint oldGWLEx = SetWindowLong(this.Handle, GWL_EXSTYLE, WS_EX_TRANSPARENT | WS_EX_LAYERED);
SetLayeredWindowAttributes(this.Handle, 0, 100, LWA_ALPHA);
}
要时窗体恢复正常，只要执行以下语句：
this.FormBorderStyle = FormBorderStyle.None;
<> <>
