程序猿对于宕机再熟悉不过了，如果一个程序异常退出，那我们只能在Windows日志中找到它的踪迹；如果它是一个托盘程序，异常退出后，它会停留在托盘中久久不能离去，直到我们的鼠标从它身上划过；如果一个程序被另一个守护程序不断的杀掉、重启，那么它的结果会如下图所示，
请注意！！这不是扫雷！！没错，这正是残留的图标。解决方法其实很简单，在程序每次开启前，向托盘窗口发送鼠标经过消息WM_MOUSEMOVE，使其刷新。
首先要明确一点，托盘包括显示区域和溢出区域，所以需要同时刷新，防止遗漏。可以用Spy++鼠标右键选择“突出显示”，窗口轮廓就会闪烁，SysPager和NotifyIconOverflowWindow。
代码如下：
using System;
using System.Runtime.InteropServices;
public class TaskBarUtil
{
struct RECT
{
public int left, top, right, bottom;
}
public static void RefreshNotification()
{
var NotifyAreaHandle = GetNotifyAreaHandle();
if (NotifyAreaHandle != IntPtr.Zero)
RefreshWindow(NotifyAreaHandle);
var NotifyOverHandle = GetNotifyOverHandle();
if (NotifyOverHandle != IntPtr.Zero)
RefreshWindow(NotifyOverHandle);
}
private static void RefreshWindow(IntPtr windowHandle)
{
const uint WM_MOUSEMOVE = 0x0200;
RECT rect;
GetClientRect(windowHandle, out rect);
for (var x = 0; x < rect.right; x += 5)
for (var y = 0; y < rect.bottom; y += 5)
SendMessage(windowHandle, WM_MOUSEMOVE, 0, (y << 16) + x);
}
private static IntPtr GetNotifyAreaHandle()
{
var TrayWndHandle = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "Shell_TrayWnd", string.Empty);
var TrayNotifyWndHandle = FindWindowEx(TrayWndHandle, IntPtr.Zero, "TrayNotifyWnd", string.Empty);
var SysPagerHandle = FindWindowEx(TrayNotifyWndHandle, IntPtr.Zero, "SysPager", string.Empty);
var NotifyAreaHandle = FindWindowEx(SysPagerHandle, IntPtr.Zero, "ToolbarWindow32", string.Empty);
return NotifyAreaHandle;
}
private static IntPtr GetNotifyOverHandle()
{
var OverHandle = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "NotifyIconOverflowWindow", string.Empty);
var NotifyOverHandle = FindWindowEx(OverHandle, IntPtr.Zero, "ToolbarWindow32", string.Empty);
return NotifyOverHandle;
}
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr FindWindowEx(IntPtr parentHandle, IntPtr childAfter, string className, string windowTitle);
[DllImport("user32.dll")]
static extern bool GetClientRect(IntPtr handle, out RECT rect);
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr handle, UInt32 message, Int32 wParam, Int32 lParam);
}
TaskBarUtil.RefreshNotification();
托盘又恢复往日简洁 ^_^