[个人框架 C_Framework] (EasyTool) MD

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

public class MD5Tool
{
    //PS说明: 
    //一般MD5默认位32位字符长度
    //16位的MD5是从32位的基础上截取中间18位,即切片[8:24]
    //64位的MD5是在32位的基础上偶数索引位,即索引位0,2,4,6...的位置前加2个0
    //128位的MD5是在32位的基础上偶数索引位,即索引位0,2,4,6...的位置前加6个0

    /// <summary>
    /// 计算文本内容的16位MD5值
    /// </summary>
    /// <param name="content">文本内容</param>
    /// <param name="isToUpper">True字符全大写 False字符全小写</param>
    /// <returns>返回MD5结果</returns>
    public static string GetMD5_16(string content, bool isToUpper = true)
    {
        return getFormatResult(getMD5Bytes(content), isToUpper ? "X2" : "x2").Substring(8, 16);
    }

    /// <summary>
    /// 计算文本内容的MD5值,默认的32位,这个比其他的方法要快一点,BitConverter比循环format要快
    /// </summary>
    /// <param name="content">文本内容</param>
    /// <param name="isToUpper">True字符全大写 False字符全小写</param>
    /// <returns>返回MD5结果</returns>
    public static string GetMD5(string content, bool isToUpper = true)
    {
        byte[] md5Bytes = getMD5Bytes(content);
        return isToUpper ? BitConverter.ToString(md5Bytes).Replace("-", "").ToUpper() : BitConverter.ToString(md5Bytes).Replace("-", "").ToLower();
    }

    /// <summary>
    /// 直接传入字节流数组,可以对非文本内容进行MD5哈希
    /// </summary>
    /// <param name="byteContent">字节数组内容</param>
    /// <param name="isToUpper">True字符全大写 False字符全小写</param>
    /// <returns>返回MD5结果</returns>
    public static string GetMD5(byte[] byteContent, bool isToUpper = true)
    {
        return getFormatResult(byteContent);
    }

    /// <summary>
    /// 计算文件的MD5值
    /// </summary>
    /// <param name="fileFullPath">文件的完整路径</param>
    /// <returns></returns>
    public static string GetMD5_File(string fileFullPath)
    {
        string fileMD5 = string.Empty;
        //检查文件是否存在,如果文件存在则进行计算,否则返回空值
        if (File.Exists(fileFullPath))
        {
            using (FileStream fs = new FileStream(fileFullPath, FileMode.Open, FileAccess.Read))
            {
                fileMD5 = getFormatResult(getMD5Bytes(fs));
            }
        }
        return fileMD5;
    }

    /// <summary>
    /// 计算文本内容的32位MD5值
    /// </summary>
    /// <param name="content">文本内容</param>
    /// <param name="isToUpper">True字符全大写 False字符全小写</param>
    /// <returns>返回MD5结果</returns>
    public static string GetMD5_32(string content, bool isToUpper = true)
    {
        return getFormatResult(getMD5Bytes(content), isToUpper ? "X2" : "x2");
    }

    /// <summary>
    /// 获取文本流的MD5字节内容
    /// </summary>
    /// <param name="content">文本内容</param>
    /// <returns>返回MD5字节内容</returns>
    static byte[] getMD5Bytes(string content)
    {
        MD5 md5 = new MD5CryptoServiceProvider();
        byte[] bytes = md5.ComputeHash(Encoding.UTF8.GetBytes(content));
        md5.Clear();
        return bytes;
    }

    /// <summary>
    /// 获取文件流的MD5字节内容
    /// </summary>
    /// <param name="fs">文件流</param>
    /// <returns>返回MD5字节内容</returns>
    static byte[] getMD5Bytes(FileStream fs)
    {
        MD5 md5 = new MD5CryptoServiceProvider();
        byte[] bytes = md5.ComputeHash(fs);
        md5.Clear();
        return bytes;
    }

    /// <summary>
    /// 获取文件流的MD5字节内容
    /// </summary>
    /// <param name="fs">文件流</param>
    /// <returns>返回MD5字节内容</returns>
    static byte[] getMD5Bytes(byte[] byts)
    {
        MD5 md5 = new MD5CryptoServiceProvider();
        byte[] bytes = md5.ComputeHash(byts);
        md5.Clear();
        return bytes;
    }

    /// <summary>
    /// 获取格式化后的结果
    /// </summary>
    /// <param name="bytes">字节数组</param>
    /// <param name="format">格式化信息</param>
    /// <returns></returns>
    static string getFormatResult(byte[] bytes, string format="X2")
    {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < bytes.Length; i++)
        {
            sb.Append(bytes[i].ToString(format));
        }
        return sb.ToString();
    }
}