C# 结构体转换byte

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices; //需要添加命名空间

namespace YuanLiChenXiao
{
    /// <summary>
    /// 消息头结构体
    /// </summary>
    [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Ansi, Pack=1)]
    public struct StructMessage
    {
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 30)]
        public byte[] fileName;             //文件名30个byte
        public long fileLength;             //文件长度8byte
    }

    public class ConverData
    {
        /// <summary>
        /// 将结构体转换成byte
        /// </summary>
        /// <param name="obj">结构体</param>
        /// <returns>byte数组</returns>
        public static byte[] StructToByte(object obj)
        {
            if (null == obj)
            {
                return null;
            }

            //长度
            int len = Marshal.SizeOf(obj);
            byte[]buffer = new byte[len];
            //从进程非托管内存中分配内存
            IntPtr ptr = Marshal.AllocHGlobal(len);
            //将数据从托管的对象封送到非托管内存
            Marshal.StructureToPtr(obj, ptr, true);
            //将数据从非托管的内存指针复制到托管
            Marshal.Copy(ptr, buffer, 0, len);
            //释放分配的内存
            Marshal.FreeHGlobal(ptr);
            return buffer;
        }

        /// <summary>
        /// 将byte[]还原成结构体
        /// </summary>
        /// <param name="buffer">byte[]</param>
        /// <param name="type"></param>
        /// <returns></returns>
        public static object ByteToStruct(byte[] buffer, Type type)
        {
            int len = Marshal.SizeOf(type);
            if (len != buffer.Length)
            {
                return null;
            }

            IntPtr ptr = Marshal.AllocHGlobal(len);
            //将托管数据复制到非托管内存
            Marshal.Copy(buffer, 0, ptr, len);

            object obj = Marshal.PtrToStructure(ptr, type);
            //释放内存
            Marshal.FreeHGlobal(ptr);
            return obj;
        }

        /// <summary>
        ///  调用
        /// </summary>
        public void UseExample()
        {
            //赋值
            StructMessage header = new StructMessage();
            header.fileLength = 9527;
            string fileName = "YuanLiChenXiao.exe";
   header.fileName = new byte[30];
   byte[] tmp = Encoding.UTF8.GetBytes(fileName);
            header.fileName = Array.Copy(tmp,header.fileName,30);

   //转换为定长38字节
            byte[] buffer = ConverData.StructToByte(header);

   //还原结构体
            StructMessage msg = (StructMessage)ConverData.ByteToStruct(buffer, typeof(StructMessage));
        }
    }
}