win32系统托盘图标，对vc编程很有帮助

很不错的一个例子，对理解系统托盘很有帮助，以后实验用得着的。

#include <windows.h>
#define IDR_PAUSE 12
#define IDR_START 13
/*
#include <shellapi.h>
#pragma   comment(lib,   "shell32.lib") 
*/
LPCTSTR szAppName = TEXT("服务程序");
LPCTSTR szWndName = TEXT("服务程序");
HMENU hmenu;//菜单句柄

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	NOTIFYICONDATA nid;
	UINT WM_TASKBARCREATED;
	POINT pt;//用于接收鼠标坐标
	int xx;//用于接收菜单选项返回值

	// 不要修改TaskbarCreated，这是系统任务栏自定义的消息
	WM_TASKBARCREATED = RegisterWindowMessage(TEXT("TaskbarCreated"));
	switch (message)
	{
	case WM_CREATE://窗口创建时候的消息.
		nid.cbSize = sizeof(nid);
		nid.hWnd = hwnd;
		nid.uID = 0;
		nid.uFlags = NIF_ICON | NIF_MESSAGE | NIF_TIP;
		nid.uCallbackMessage = WM_USER;
		nid.hIcon = LoadIcon(NULL, IDI_APPLICATION);
		lstrcpy(nid.szTip, szAppName);
		Shell_NotifyIcon(NIM_ADD, &nid);
		hmenu=CreatePopupMenu();//生成菜单
		AppendMenu(hmenu,MF_STRING,IDR_PAUSE,"暂停服务");//为菜单添加两个选项
		AppendMenu(hmenu,MF_STRING,IDR_START,"恢复服务");
		break;
	case WM_USER://连续使用该程序时候的消息.
		if (lParam == WM_LBUTTONDOWN)
			MessageBox(hwnd, TEXT("Win32 API 实现系统托盘程序,双击托盘可以退出!"), szAppName, MB_OK);
		if (lParam == WM_LBUTTONDBLCLK)//双击托盘的消息,退出.
			SendMessage(hwnd, WM_CLOSE, wParam, lParam);
		if (lParam == WM_RBUTTONDOWN)
		{
			GetCursorPos(&pt);//取鼠标坐标
			::SetForegroundWindow(hwnd);//解决在菜单外单击左键菜单不消失的问题
			EnableMenuItem(hmenu,IDR_PAUSE,MF_GRAYED);//让菜单中的某一项变灰
			xx=TrackPopupMenu(hmenu,TPM_RETURNCMD,pt.x,pt.y,NULL,hwnd,NULL);//显示菜单并获取选项ID
			if(xx==IDR_PAUSE) MessageBox(hwnd, TEXT("111"), szAppName, MB_OK);
			if(xx==IDR_START) MessageBox(hwnd, TEXT("222"), szAppName, MB_OK);
			if(xx==0) PostMessage(hwnd,WM_LBUTTONDOWN,NULL,NULL);
			//MessageBox(hwnd, TEXT("右键"), szAppName, MB_OK);
		}
		break;
	case WM_DESTROY://窗口销毁时候的消息.
		Shell_NotifyIcon(NIM_DELETE, &nid);
		PostQuitMessage(0);
		break;
	default:
		/*
		* 防止当Explorer.exe 崩溃以后，程序在系统系统托盘中的图标就消失
		*
		* 原理：Explorer.exe 重新载入后会重建系统任务栏。当系统任务栏建立的时候会向系统内所有
		* 注册接收TaskbarCreated 消息的顶级窗口发送一条消息，我们只需要捕捉这个消息，并重建系
		* 统托盘的图标即可。
		*/
		if (message == WM_TASKBARCREATED)
			SendMessage(hwnd, WM_CREATE, wParam, lParam);
		break;
	}
	return DefWindowProc(hwnd, message, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
				   LPSTR szCmdLine, int iCmdShow)
{
	HWND hwnd;
	MSG msg;
	WNDCLASS wndclass;

	HWND handle = FindWindow(NULL, szWndName);
	if (handle != NULL)
	{
		MessageBox(NULL, TEXT("Application is already running"), szAppName, MB_ICONERROR);
		return 0;
	}

	wndclass.style = CS_HREDRAW | CS_VREDRAW;
	wndclass.lpfnWndProc = WndProc;
	wndclass.cbClsExtra = 0;
	wndclass.cbWndExtra = 0;
	wndclass.hInstance = hInstance;
	wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
	wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
	wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	wndclass.lpszMenuName = NULL;
	wndclass.lpszClassName = szAppName;

	if (!RegisterClass(&wndclass))
	{
		MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR);
		return 0;
	}

	// 此处使用WS_EX_TOOLWINDOW 属性来隐藏显示在任务栏上的窗口程序按钮
	hwnd = CreateWindowEx(WS_EX_TOOLWINDOW,
		szAppName, szWndName,
		WS_POPUP,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		NULL, NULL, hInstance, NULL);

	ShowWindow(hwnd, iCmdShow);
	UpdateWindow(hwnd);

	while (GetMessage(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	return msg.wParam;
}