获取一个文件的MD5值

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.IO;

/// <summary>
/// MyHash 的摘要说明
/// </summary>
public class MyHash
{
    public MyHash()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }

    /// <summary>
    /// 获取一个文件的Hah值
    /// </summary>
    /// <param name="path"></param>
    /// <returns></returns>
    public static string GetHashByFilePath(string path)
    {
        try
        {
            FileStream file = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
            System.Security.Cryptography.MD5CryptoServiceProvider md5Code = new System.Security.Cryptography.MD5CryptoServiceProvider();
            byte[] hash_byte = md5Code.ComputeHash(file);
            file.Close();
            string res = System.BitConverter.ToString(hash_byte);
            res = res.Replace("-", "");
            return res;
        }
        catch (Exception e)
        {
            return "";
        }
    }

    /// <summary>
    /// 获取一个文件流的Hah值
    /// </summary>
    /// <param name="stream"></param>
    /// <returns></returns>
    public static string GetHashByStream(Stream stream)
    {
        try
        {
            System.Security.Cryptography.MD5CryptoServiceProvider md5Code = new System.Security.Cryptography.MD5CryptoServiceProvider();
            byte[] hash_byte = md5Code.ComputeHash(stream);
            string res = System.BitConverter.ToString(hash_byte);
            res = res.Replace("-", "");
            return res;
        }
        catch (Exception e)
        {
            return "";
        }
    }
}