一、调用Windows API
C#下调用Windows API方法如下：
1、引入命名空间：using System.Runtime.InteropServices;
2、引用需要使用的方法，格式：[DllImport("DLL文件")]方法的声明;
[DllImport("user32.dll")]private static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);[DllImport("user32.dll")]private static extern bool SetForegroundWindow(IntPtr hWnd);[DllImport("user32.dll")]private static extern IntPtr FindWindow(string lpClassName,string lpWindowName);[DllImport("user32.dll")]private static extern int SendMessage(IntPtr hWnd,int Msg,int wParam,int lParam);[DllImport("user32.dll")]private static extern bool SetCursorPos(int X, int Y);[DllImport("user32.dll")]private static extern void mouse_event(int dwFlags, int dx, int dy, int dwData, int dwExtraInfo);[DllImport("user32.dll")]private static extern void keybd_event(byte bVk, byte bScan, uint dwFlags, uint dwExtraInfo);[DllImport("user32.dll")]private static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndlnsertAfter, int X, int Y, int cx, int cy, uint Flags);//ShowWindow参数private const int SW_SHOWNORMAL = 1;private const int SW_RESTORE = 9;private const int SW_SHOWNOACTIVATE = 4;//SendMessage参数private const int WM_KEYDOWN = 0X100;private const int WM_KEYUP = 0X101;private const int WM_SYSCHAR = 0X106;private const int WM_SYSKEYUP = 0X105;private const int WM_SYSKEYDOWN = 0X104;private const int WM_CHAR = 0X102; //ShowWindow参数 //显示Window
//SendMessage参数 //发送信息
二、找到目标窗口
1)、根据窗口的标题得到句柄
IntPtr myIntPtr = FindWindow(null,"窗口名"); //null为类名，可以用Spy++得到，也可以为空ShowWindow(myIntPtr, SW_RESTORE); //将窗口还原SetForegroundWindow(myIntPtr); //如果没有ShowWindow，此方法不能设置最小化的窗口2)、遍历所有窗口得到句柄
1.定义委托方法CallBack，枚举窗口API（EnumWindows），得到窗口名API（GetWindowTextW）和得到窗口类名API（GetClassNameW）。
public delegate bool CallBack(int hwnd, int lParam);[DllImport("user32")]public static extern int EnumWindows(CallBack x, int y);[DllImport("user32.dll")]private static extern int GetWindowTextW(IntPtr hWnd, [MarshalAs(UnmanagedType.LPWStr)]StringBuilder lpString, int nMaxCount);[DllImport("user32.dll")]private static extern int GetClassNameW(IntPtr hWnd, [MarshalAs(UnmanagedType.LPWStr)]StringBuilder lpString, int nMaxCount);2.调用EnumWindows遍历窗口
CallBack myCallBack = new CallBack(Recall);EnumWindows(myCallBack, 0);3.回调方法Recall
public bool Recall(int hwnd, int lParam){StringBuilder sb = new StringBuilder(256);IntPtr PW = new IntPtr(hwnd);GetWindowTextW(PW,sb,sb.Capacity); //得到窗口名并保存在strName中string strName = sb.ToString();GetClassNameW(PW,sb,sb.Capacity); //得到窗口类名并保存在strClass中string strClass = sb.ToString();if (strName.IndexOf("窗口名关键字") >= 0 && strClass.IndexOf("类名关键字") >= 0){return false; //返回false中止EnumWindows遍历}else{return true; //返回true继续EnumWindows遍历}}3)、打开窗口得到句柄
1.定义设置活动窗口API（SetActiveWindow），设置前台窗口API（SetForegroundWindow）。
[DllImport("user32.dll")]static extern IntPtr SetActiveWindow(IntPtr hWnd);[DllImport("user32.dll")][return: MarshalAs(UnmanagedType.Bool)]static extern bool SetForegroundWindow(IntPtr hWnd);2.打开窗口
Process proc = Process.Start(@"目标程序路径");SetActiveWindow(proc.MainWindowHandle);SetForegroundWindow(proc.MainWindowHandle);三、向指定的窗口输入数据
1.利用发送消息API（SendMessage）向窗口发送数据。
InputStr(myIntPtr, _GameID); //输入游戏IDSendMessage(myIntPtr, WM_SYSKEYDOWN, 0X09, 0); //输入TAB（0x09）SendMessage(myIntPtr, WM_SYSKEYUP, 0X09, 0);InputStr(myIntPtr, _GamePass); //输入游戏密码SendMessage(myIntPtr, WM_SYSKEYDOWN, 0X0D, 0); //输入ENTER（0x0d）SendMessage(myIntPtr, WM_SYSKEYUP, 0X0D, 0);/// <summary>/// 发送一个字符串/// </summary>/// <param name="myIntPtr">窗口句柄</param>/// <param name="Input">字符串</param>public void InputStr(IntPtr myIntPtr, string Input){byte[] ch = (ASCIIEncoding.ASCII.GetBytes(Input));for (int i = 0; i < ch.Length; i++){SendMessage(PW, WM_CHAR, ch, 0);}}2.利用鼠标和键盘模拟向窗口发送数据。
SetWindowPos(PW, (IntPtr)(-1), 0, 0, 0, 0, 0x0040 | 0x0001); //设置窗口位置SetCursorPos(476, 177); //设置鼠标位置mouse_event(0x0002, 0, 0, 0, 0); //模拟鼠标按下操作mouse_event(0x0004, 0, 0, 0, 0); //模拟鼠标放开操作SendKeys.Send(_GameID); //模拟键盘输入游戏IDSendKeys.Send("{TAB}"); //模拟键盘输入TABSendKeys.Send(_GamePass); //模拟键盘输入游戏密码SendKeys.Send("{ENTER}"); //模拟键盘输入ENTER另：上面还提到了keybd_event方法，用法和mouse_event方法类似，作用和SendKeys.Send一样。