[讨论]一个关屏程序分别用c#.net cf 和 evc++实现的不同

应哥们要求写了个关闭屏幕的小程序，vs.net 2005基于c++实现， 文件大小执行效率都还可以。不过当时写的匆忙很糙的，图标就用默认那个巨难看的！昨天哥们说让我加个图标，我说我用c#重写吧，图标加着方便，于是用C#重写，虽然文件大小只有8K较c++的32K要小很多，但是执行效率非常低下！分析个中原因，大概是因为c++和c#.net程序的执行方式不同造成的吧，c++是传统的执行方式，而.net则是类似于java的解释执行方式，也许在PC上这种差别可以忽略，但是PPC这种对资源敏感的系统差别就出现了。下面是两种语言的实现代码：
c++：

// CloseScreen.cpp : Defines the entry point for the application.
//

#include "stdafx.h"
#include "CloseScreen.h"
#include <windows.h>
#include <commctrl.h>

#define MAX_LOADSTRING 100

// Global Variables:
HINSTANCE g_hInst; // current instance
HWND g_hWndMenuBar; // menu bar handle

// Forward declarations of functions included in this code module:
ATOM MyRegisterClass(HINSTANCE, LPTSTR);
BOOL InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPTSTR lpCmdLine,
int nCmdShow)
{
MSG msg;

// Perform application initialization:
if (!InitInstance(hInstance, nCmdShow))
{
return FALSE;
}

HACCEL hAccelTable;
hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_CLOSESCREEN));

// Main message loop:
while (GetMessage(&msg, NULL, 0, 0))
{
if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}

return (int) msg.wParam;
}

//
// FUNCTION: MyRegisterClass()
//
// PURPOSE: Registers the window class.
//
// COMMENTS:
//
ATOM MyRegisterClass(HINSTANCE hInstance, LPTSTR szWindowClass)
{
WNDCLASS wc;

wc.style = CS_HREDRAW | CS_VREDRAW;
wc.lpfnWndProc = WndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_CLOSESCREEN));
wc.hCursor = 0;
wc.hbrBackground = (HBRUSH) GetStockObject(WHITE_BRUSH);
wc.lpszMenuName = 0;
wc.lpszClassName = szWindowClass;

return RegisterClass(&wc);
}

//
// FUNCTION: InitInstance(HINSTANCE, int)
//
// PURPOSE: Saves instance handle and creates main window
//
// COMMENTS:
//
// In this function, we save the instance handle in a global variable and
// create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
HWND hWnd;
TCHAR szTitle[MAX_LOADSTRING]; // title bar text
TCHAR szWindowClass[MAX_LOADSTRING]; // main window class name

g_hInst = hInstance; // Store instance handle in our global variable

// SHInitExtraControls should be called once during your application's initialization to initialize any
// of the device specific controls such as CAPEDIT and SIPPREF.
SHInitExtraControls();

LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
LoadString(hInstance, IDC_CLOSESCREEN, szWindowClass, MAX_LOADSTRING);

//If it is already running, then focus on the window, and exit
hWnd = FindWindow(szWindowClass, szTitle);
if (hWnd)
{
// set focus to foremost child window
// The "| 0x00000001" is used to bring any owned windows to the foreground and
// activate them.
SetForegroundWindow((HWND)((ULONG) hWnd | 0x00000001));
return 0;
}

if (!MyRegisterClass(hInstance, szWindowClass))
{
return FALSE;
}

hWnd = CreateWindow(szWindowClass, szTitle, WS_VISIBLE,
CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);

if (!hWnd)
{
return FALSE;
}

// When the main window is created using CW_USEDEFAULT the height of the menubar (if one
// is created is not taken into account). So we resize the window after creating it
// if a menubar is present
if (g_hWndMenuBar)
{
RECT rc;
RECT rcMenuBar;

GetWindowRect(hWnd, &rc);
GetWindowRect(g_hWndMenuBar, &rcMenuBar);
rc.bottom -= (rcMenuBar.bottom - rcMenuBar.top);

MoveWindow(hWnd, rc.left, rc.top, rc.right-rc.left, rc.bottom-rc.top, FALSE);
}

ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);

return TRUE;
}

//
// FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// PURPOSE: Processes messages for the main window.
//
// WM_COMMAND - process the application menu
// WM_PAINT - Paint the main window
// WM_DESTROY - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
int wmId, wmEvent;
PAINTSTRUCT ps;
HDC hdc;

static SHACTIVATEINFO s_sai;

switch (message)
{
case WM_COMMAND:
wmId = LOWORD(wParam);
wmEvent = HIWORD(wParam);
// Parse the menu selections:
switch (wmId)
{
case IDM_HELP_ABOUT:
DialogBox(g_hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, About);
break;
case IDM_OK:
SendMessage (hWnd, WM_CLOSE, 0, 0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
break;
case WM_CREATE:
SHMENUBARINFO mbi;

memset(&mbi, 0, sizeof(SHMENUBARINFO));
mbi.cbSize = sizeof(SHMENUBARINFO);
mbi.hwndParent = hWnd;
mbi.nToolBarId = IDR_MENU;
mbi.hInstRes = g_hInst;

if (!SHCreateMenuBar(&mbi))
{
g_hWndMenuBar = NULL;
}
else
{
g_hWndMenuBar = mbi.hwndMB;
}

// Initialize the shell activate info structure
memset(&s_sai, 0, sizeof (s_sai));
s_sai.cbSize = sizeof (s_sai);
//实现
keybd_event(VK_OFF, 0, 0, 0); // down
keybd_event(VK_OFF, 0, 2, 0); // up
SendMessage(hWnd, WM_CLOSE, 0, 0);

break;
case WM_PAINT:
hdc = BeginPaint(hWnd, &ps);

// TODO: Add any drawing code here...

EndPaint(hWnd, &ps);
break;
case WM_DESTROY:
CommandBar_Destroy(g_hWndMenuBar);
PostQuitMessage(0);
break;

case WM_ACTIVATE:
// Notify shell of our activate message
SHHandleWMActivate(hWnd, wParam, lParam, &s_sai, FALSE);
break;
case WM_SETTINGCHANGE:
SHHandleWMSettingChange(hWnd, wParam, lParam, &s_sai);
break;

default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}

// Message handler for about box.
INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_INITDIALOG:
{
// Create a Done button and size it.
SHINITDLGINFO shidi;
shidi.dwMask = SHIDIM_FLAGS;
shidi.dwFlags = SHIDIF_DONEBUTTON | SHIDIF_SIPDOWN | SHIDIF_SIZEDLGFULLSCREEN | SHIDIF_EMPTYMENU;
shidi.hDlg = hDlg;
SHInitDialog(&shidi);
}
return (INT_PTR)TRUE;

case WM_COMMAND:
if (LOWORD(wParam) == IDOK)
{
EndDialog(hDlg, LOWORD(wParam));
return TRUE;
}
break;

case WM_CLOSE:
EndDialog(hDlg, message);
return TRUE;

#ifdef _DEVICE_RESOLUTION_AWARE
case WM_SIZE:
{
DRA::RelayoutDialog(
g_hInst,
hDlg,
DRA::GetDisplayMode() != DRA::Portrait ? MAKEINTRESOURCE(IDD_ABOUTBOX_WIDE) : MAKEINTRESOURCE(IDD_ABOUTBOX));
}
break;
#endif
}
return (INT_PTR)FALSE;
}

C#.net
#region Using directives

using System;
using System.Drawing;
using System.Collections;
using System.Windows.Forms;
using System.Data;
using System.Runtime.InteropServices;

#endregion

namespace CloseScreen
{
/// <summary>
/// Summary description for form.
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
/// <summary>
/// Main menu for the form.
/// </summary>
private System.Windows.Forms.MainMenu mainMenu1;

public Form1()
{
InitializeComponent();
}

/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
}

#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.mainMenu1 = new System.Windows.Forms.MainMenu();
//
// Form1
//
this.ClientSize = new System.Drawing.Size(240, 268);
this.Menu = this.mainMenu1;
this.Text = "CloseScreen";
this.Load += new System.EventHandler(this.Form1_Load);

}

#endregion

/// <summary>
/// The main entry point for the application.
/// </summary>
static void Main()
{
Application.Run(new Form1());
}

[DllImport("coredll.dll")]
private static extern IntPtr keybd_event(byte bVk, byte bScan, int dwFlags, int dwExtraInfo);

private void Form1_Load(object sender, EventArgs e)
{
//实现
keybd_event(0xdf, 0, 0, 0); // down
keybd_event(0xdf, 0, 2, 0); // up
this.Close();
}

}
}

不过这两个程序我都没有尝试控制台方式，也许控制台方式就没有多大差别了！