C#字符串加密与解密

1.引用：

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

2.代码

static string encryptKey = "abcd";//字符串加密密钥(注意：密钥只能是4位)

public string Encrypt(string str)
{//加密字符串

try
{
byte[] key = Encoding.Unicode.GetBytes(encryptKey);//密钥
byte[] data = Encoding.Unicode.GetBytes(str);//待加密字符串

DESCryptoServiceProvider descsp = new DESCryptoServiceProvider();//加密、解密对象
MemoryStream MStream = new MemoryStream();//内存流对象

//用内存流实例化加密流对象
CryptoStream CStream = new CryptoStream(MStream, descsp.CreateEncryptor(key, key), CryptoStreamMode.Write);
CStream.Write(data, 0, data.Length);//向加密流中写入数据
CStream.FlushFinalBlock();//将数据压入基础流
byte[] temp = MStream.ToArray();//从内存流中获取字节序列
CStream.Close();//关闭加密流
MStream.Close();//关闭内存流

return Convert.ToBase64String(temp);//返回加密后的字符串
}
catch
{
return str;
}
}

public string Decrypt(string str)
{//解密字符串

try
{
byte[] key = Encoding.Unicode.GetBytes(encryptKey);//密钥
byte[] data = Convert.FromBase64String(str);//待解密字符串

DESCryptoServiceProvider descsp = new DESCryptoServiceProvider();//加密、解密对象
MemoryStream MStream = new MemoryStream();//内存流对象

//用内存流实例化解密流对象
CryptoStream CStream = new CryptoStream(MStream, descsp.CreateDecryptor(key, key), CryptoStreamMode.Write);
CStream.Write(data, 0, data.Length);//向加密流中写入数据
CStream.FlushFinalBlock();//将数据压入基础流
byte[] temp = MStream.ToArray();//从内存流中获取字节序列
CStream.Close();//关闭加密流
MStream.Close();//关闭内存流

return Encoding.Unicode.GetString(temp);//返回解密后的字符串
}
catch
{
return str;
}
}

参考：https://www.cnblogs.com/nb08611033/p/9183198.html