Windows API中几个函数的总结

  [DllImport("User32.dll", EntryPoint = "FindWindow")]

        public static extern IntPtr FindWindow(String className, String captionName);

        [DllImport("User32.dll", EntryPoint = "FindWindowEx")]

        public static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow);

        [DllImport("User32.dll", EntryPoint = "SendMessage")]

        public static extern string  SendMessage(IntPtr hWnd, int Msg, int wParm, int lParm);

        [DllImport("User32.dll", EntryPoint = "GetWindowText")]

        public static extern int GetWindowText(IntPtr hwnd, StringBuilder lpString, int cch);





        public IntPtr getHandleParent(string classname, string captionname)

        {

            IntPtr handle = FindWindow(classname, captionname);

            return handle;

        }

        public IntPtr getHandleChild(IntPtr hwndparent,  string lpszclass, string lpszwindow)

        {

            IntPtr handle = IntPtr.Zero;

            if (hwndparent != IntPtr.Zero)

            {

                handle = FindWindowEx(hwndparent,handle,lpszclass, lpszwindow);



            }

            else

            {

                MessageBox.Show("没有找到子窗口");

            }

            return handle;

        }

      

        public string getTxt(IntPtr ChildHandle)

        {

            StringBuilder s = new StringBuilder(512);

            if (ChildHandle != IntPtr.Zero)

            {

                int i = GetWindowText(ChildHandle, s, s.Capacity);



            }

            else

            {

                MessageBox.Show("子窗口中没有内容");

            }

            return s.ToString();

            

           

        }