c# API 取得窗体的内容

c# API 获得窗体的内容
有个软件是delphi写 上面有个panel控件 内面有个webbrowser 控件
我想得到webbrowser 里面的内容

C# code

[DllImport("user32.dll", EntryPoint = "FindWindow", CharSet = CharSet.Ansi)]          public static extern IntPtr FindWindow(string className, string windowName);         [DllImport("user32.dll", EntryPoint = "GetWindowText", CharSet = CharSet.Ansi)]        public static extern bool GetWindowText(IntPtr hWnd, [OutAttribute()] StringBuilder strNewWindowName, Int32 maxCharCount);