ACAT.Lib.Core.Utility.User32Interop.GetClassLongPtr64 C# (CSharp) Метод

        public static extern IntPtr GetClassLongPtr64(IntPtr hWnd, int nIndex);

        /// <summary>
        /// Gets window class long pointer for hWnd
        /// </summary>
        /// <param name="hWnd">window handle</param>
        /// <param name="nIndex">index number</param>
        /// <returns>window class long</returns>
        private static IntPtr getClassLongPtr(IntPtr hWnd, int nIndex)
        {
            try
            {
                if (IntPtr.Size > 4)
                {
                    return(User32Interop.GetClassLongPtr64(hWnd, nIndex));
                }

                uint ret = User32Interop.GetClassLongPtr32(hWnd, nIndex);
                return(new IntPtr((int)ret));  // without the cast, it may result in an overflow
            }
            catch
            {
                return(IntPtr.Zero);
            }
        }