MD5加密

首先引入命名空间：
using System.Security.Cryptography;

//传入字符串，返回即可得到加密后的字符串

public static string MD5(string encryptString)
{
byte[] result = Encoding.Default.GetBytes(encryptString);
MD5 md5 = new MD5CryptoServiceProvider();
byte[] output = md5.ComputeHash(result);
string encryptResult = BitConverter.ToString(output).Replace("-", "");
return encryptResult;
}