P / Invoke various summaries (a, used to control the characteristics of the memory structure StructLayout)

C # when calling WInAPI function, you may see the following statement

1 [StructLayout(LayoutKind.Sequential)]
2         public struct RECT
3         {
4             public int Left;
5             public int Top;
6             public int Right;
7             public int Bottom;
8         }

In front of the belt structure or class

[StructLayout(LayoutKind.Sequential)]

StructLayoutAttribute characteristic effect you are allowed to control the physical layout of the data field structure or class memory.

When we use the normal class or structure the code in C #, the need to use this feature. However, the interaction unmanaged code, required to control the characteristic StructLayoutAttribute unmanaged type layout.

StructLayoutAttribute constructor is used:

StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind)

System.Runtime.InteropServices.LayoutKind is an enumeration type, there are three values.

LayoutKind.Sequential: Forced order of display members arranged in its