本文实例讲述了C#计算字符串哈希值（MD5、SHA）的方法。分享给大家供大家参考。具体如下：

一、关于本文

本文中是一个类库，包括下面几个函数：

① 计算32位MD5码（大小写）：Hash_MD5_32

② 计算16位MD5码（大小写）：Hash_MD5_16

③ 计算32位2重MD5码（大小写）：Hash_2_MD5_32

④ 计算16位2重MD5码（大小写）：Hash_2_MD5_16

⑤ 计算SHA-1码（大小写）：Hash_SHA_1

⑥ 计算SHA-256码（大小写）：Hash_SHA_256

⑦ 计算SHA-384码（大小写）：Hash_SHA_384

⑧ 计算SHA-512码（大小写）：Hash_SHA_512

编译后被打包成文件HashTools.dll，其他程序可以在添加引用后对这些函数进行调用

二、类库中各函数代码

1. 类库结构

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace HashTools{ public class HashHelper { //各个函数 }}

2. 计算32位MD5码（大小写）：Hash_MD5_32

/// <summary>/// 计算32位MD5码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_MD5_32(string word, bool toUpper = true){ try { System.Security.Cryptography.MD5CryptoServiceProvider MD5CSP = new System.Security.Cryptography.MD5CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = MD5CSP.ComputeHash(bytValue); MD5CSP.Clear(); //根据计算得到的Hash码翻译为MD5码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

3. 计算16位MD5码（大小写）：Hash_MD5_16

/// <summary>/// 计算16位MD5码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_MD5_16(string word, bool toUpper = true){ try { string sHash = Hash_MD5_32(word).Substring(8, 16); return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

4. 计算32位2重MD5码（大小写）：Hash_2_MD5_32

/// <summary>/// 计算32位2重MD5码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_2_MD5_32(string word, bool toUpper = true){ try { System.Security.Cryptography.MD5CryptoServiceProvider MD5CSP = new System.Security.Cryptography.MD5CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = MD5CSP.ComputeHash(bytValue); //根据计算得到的Hash码翻译为MD5码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } bytValue = System.Text.Encoding.UTF8.GetBytes(sHash); bytHash = MD5CSP.ComputeHash(bytValue); MD5CSP.Clear(); sHash = ""; //根据计算得到的Hash码翻译为MD5码 for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

5. 计算16位2重MD5码（大小写）：Hash_2_MD5_16

/// <summary>/// 计算16位2重MD5码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_2_MD5_16(string word, bool toUpper = true){ try { System.Security.Cryptography.MD5CryptoServiceProvider MD5CSP = new System.Security.Cryptography.MD5CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = MD5CSP.ComputeHash(bytValue); //根据计算得到的Hash码翻译为MD5码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } sHash = sHash.Substring(8, 16); bytValue = System.Text.Encoding.UTF8.GetBytes(sHash); bytHash = MD5CSP.ComputeHash(bytValue); MD5CSP.Clear(); sHash = ""; //根据计算得到的Hash码翻译为MD5码 for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } sHash = sHash.Substring(8, 16); //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

6. 计算SHA-1码（大小写）：Hash_SHA_1

/// <summary>/// 计算SHA-1码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_SHA_1(string word, bool toUpper = true){ try { System.Security.Cryptography.SHA1CryptoServiceProvider SHA1CSP = new System.Security.Cryptography.SHA1CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = SHA1CSP.ComputeHash(bytValue); SHA1CSP.Clear(); //根据计算得到的Hash码翻译为SHA-1码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

7. 计算SHA-256码（大小写）：Hash_SHA_256

/// <summary>/// 计算SHA-256码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_SHA_256(string word, bool toUpper = true){ try { System.Security.Cryptography.SHA256CryptoServiceProvider SHA256CSP = new System.Security.Cryptography.SHA256CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = SHA256CSP.ComputeHash(bytValue); SHA256CSP.Clear(); //根据计算得到的Hash码翻译为SHA-1码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

8. 计算SHA-384码（大小写）：Hash_SHA_384

/// <summary>/// 计算SHA-384码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_SHA_384(string word, bool toUpper = true){ try { System.Security.Cryptography.SHA384CryptoServiceProvider SHA384CSP = new System.Security.Cryptography.SHA384CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = SHA384CSP.ComputeHash(bytValue); SHA384CSP.Clear(); //根据计算得到的Hash码翻译为SHA-1码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

9. 计算SHA-512码（大小写）：Hash_SHA_512

/// <summary>/// 计算SHA-512码/// </summary>/// <param name="word">字符串</param>/// <param name="toUpper">返回哈希值格式 true：英文大写，false：英文小写</param>/// <returns></returns>public static string Hash_SHA_512(string word, bool toUpper = true){ try { System.Security.Cryptography.SHA512CryptoServiceProvider SHA512CSP = new System.Security.Cryptography.SHA512CryptoServiceProvider(); byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(word); byte[] bytHash = SHA512CSP.ComputeHash(bytValue); SHA512CSP.Clear(); //根据计算得到的Hash码翻译为SHA-1码 string sHash = "", sTemp = ""; for (int counter = 0; counter < bytHash.Count(); counter++) { long i = bytHash[counter] / 16; if (i > 9) { sTemp = ((char)(i - 10 + 0x41)).ToString(); } else { sTemp = ((char)(i + 0x30)).ToString(); } i = bytHash[counter] % 16; if (i > 9) { sTemp += ((char)(i - 10 + 0x41)).ToString(); } else { sTemp += ((char)(i + 0x30)).ToString(); } sHash += sTemp; } //根据大小写规则决定返回的字符串 return toUpper ? sHash : sHash.ToLower(); } catch (Exception ex) { throw new Exception(ex.Message); }}

三、函数调用

建立项目ComputeHash，添加对HashTools.dll库的引用。并添加代码：
复制代码 代码如下:using HashTools;
然后在Main函数中添加下列代码：

static void Main(string[] args){ Console.WriteLine("MD5 of \"abc\""); Console.WriteLine("MD5_32(Upper): {0}", HashHelper.Hash_MD5_32("abc")); Console.WriteLine("MD5_32(Lower): {0}", HashHelper.Hash_MD5_32("abc", false)); Console.WriteLine("MD5_16(Upper): {0}", HashHelper.Hash_MD5_16("abc")); Console.WriteLine("MD5_16(Lower): {0}", HashHelper.Hash_MD5_16("abc", false)); Console.WriteLine("2_MD5_32(Upper): {0}", HashHelper.Hash_2_MD5_32("abc")); Console.WriteLine("2_MD5_32(Lower): {0}", HashHelper.Hash_2_MD5_32("abc", false)); Console.WriteLine("2_MD5_32(Upper): {0}", HashHelper.Hash_2_MD5_16("abc")); Console.WriteLine("2_MD5_32(Lower): {0}", HashHelper.Hash_2_MD5_16("abc", false)); Console.WriteLine("SHA of \"abc\""); Console.WriteLine("SHA-1(Upper): {0}", HashHelper.Hash_SHA_1("abc")); Console.WriteLine("SHA-1(Lower): {0}", HashHelper.Hash_SHA_1("abc", false)); Console.WriteLine("SHA-256(Upper): {0}", HashHelper.Hash_SHA_256("abc")); Console.WriteLine("SHA-256(Lower): {0}", HashHelper.Hash_SHA_256("abc", false)); Console.WriteLine("SHA-384(Upper): {0}", HashHelper.Hash_SHA_384("abc")); Console.WriteLine("SHA-384(Lower): {0}", HashHelper.Hash_SHA_384("abc", false)); Console.WriteLine("SHA-512(Upper): {0}", HashHelper.Hash_SHA_512("abc")); Console.WriteLine("SHA-512(Lower): {0}", HashHelper.Hash_SHA_512("abc", false)); Console.ReadLine();}

运行结果如下：

希望本文所述对大家的C#程序设计有所帮助。