VC风格struct定义

1、

        [StructLayout(LayoutKind.Sequential)]
        public struct Point
        {
            public int x;
            public int y;
        } 

        [StructLayout(LayoutKind.Explicit)]
        public struct Rect
        {
            [FieldOffset(0)] public int left;
            [FieldOffset(4)] public int top;
            [FieldOffset(8)] public int right;
            [FieldOffset(12)] public int bottom;
        }

2、