计算文件MD5码的工具

using System.IO;
using System.Security.Cryptography;
using System.Text;


/// <summary>
/// 计算文件的MD5码
/// </summary>
public class ComputeFileMD5
{
    #region 私有变量及属性

    /// <summary>
    /// MD5对象
    /// </summary>
    private MD5 md5Obj;
    /// <summary>
    /// MD5属性
    /// </summary>
    private MD5 MD5Obj
    {
        get { return md5Obj ?? (md5Obj = MD5.Create()); }
    }

    #endregion

    #region 私有方法

    /// <summary>
    /// 计算一个字节数组的MD5码
    /// </summary>
    /// <param name="bytes">参与计算的字节数组</param>
    /// <returns>结算获得的MD5码</returns>
    private string ComputeHash(byte[] bytes)
    {
        if (null == bytes || bytes.Length <= 0)
            return "";
        byte[] hash = MD5Obj.ComputeHash(bytes);
        StringBuilder sb = new StringBuilder();
        foreach (var data in hash)
        {
            sb.Append(data.ToString("x2"));
        }
        return sb.ToString();
    }

    /// <summary>
    /// 将文件读取为字节数组
    /// </summary>
    /// <param name="filePath">文件路径</param>
    /// <returns>字节数组读取结果</returns>
    private byte[] ReadBytesFromFile(string filePath)
    {
        if (string.IsNullOrEmpty(filePath))
            return null;

        return File.ReadAllBytes(filePath);
    }

    #endregion


    #region 公有方法

    /// <summary>
    /// 计算文件的MD5码
    /// </summary>
    /// <param name="filePath">文件路径</param>
    /// <returns>文件计算获得的MD5码</returns>
    public string ComputeMD5(string filePath)
    {
        if (!File.Exists(filePath))
            return "";
        byte[] bytes = ReadBytesFromFile(filePath);
        return null != bytes ? ComputeHash(bytes) : null;
    }

    #endregion
}

测试用例:

using System;

namespace myMethod
{
    class lgs
    {
        static void Main()
        {
            ComputeFileMD5 tool = new ComputeFileMD5();
            string path = @"D:DOTween Pro 0.9.690.unitypackage";
            string md5 = tool.ComputeMD5(path);
            Console.WriteLine(md5);
            Console.ReadKey();
        }
    }
}

输出结果: