防止多重启动之调用Api [收集2005090201]

防止多重启动之调用Api (效果:第二次启动程序则前一进程的窗口跳到最前)

using System.Threading;

private const int SW_NORMAL = 1; // see WinUser.h for definitions
  private const int SW_RESTORE = 9;

  [DllImport("User32",EntryPoint="FindWindow")]
  static extern IntPtr FindWindow(string className, string windowName);

  [DllImport("User32",EntryPoint="SendMessage")]
  private static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);

  [DllImport("User32",EntryPoint="SetForegroundWindow")]
  private static extern bool SetForegroundWindow(IntPtr hWnd);

  [DllImport("User32",EntryPoint="SetWindowPlacement")]
  private static extern bool SetWindowPlacement(IntPtr hWnd, [In] ref WINDOWPLACEMENT lpwndpl);

  [DllImport("User32",EntryPoint="GetWindowPlacement")]
  private static extern bool GetWindowPlacement(IntPtr hWnd, [In] ref WINDOWPLACEMENT lpwndpl);

  private struct POINTAPI
  {
   public int x;
   public int y;
  }

  private struct RECT
  {
   public int left;
   public int top;
   public int right;
   public int bottom;
  }

  private struct WINDOWPLACEMENT
  {
   public int length;
   public int flags;
   public int showCmd;
   public POINTAPI ptMinPosition;
   public POINTAPI ptMaxPosition;
   public RECT rcNormalPosition;
  }                                             


//Main
static void Main()
  {

   bool createdNew;

   System.Threading.Mutex m = new System.Threading.Mutex(true, "yourApp", out createdNew);

   if (! createdNew)
   {
    // see if we can find the other app and Bring it to front
    IntPtr hWnd = FindWindow(null, "form1deText");

  
    if(hWnd != IntPtr.Zero)
    {
     form1.WINDOWPLACEMENT placement = new form1.WINDOWPLACEMENT();
     placement.length = Marshal.SizeOf(placement);

     GetWindowPlacement(hWnd, ref placement);

     if(placement.showCmd != SW_NORMAL)
     {
      placement.showCmd = SW_RESTORE;

      SetWindowPlacement(hWnd, ref placement);
      SetForegroundWindow(hWnd);
     }
    }

    return;
   }

   Application.Run(new form1());

   // keep the mutex reference alive until the normal termination of the program
   GC.KeepAlive(m);

  }