C#原生加密方法： System.Security.Cryptography.CryptoStream DataSet加密解密

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace CryptoHelperLib
{
public class CryptoHelper
{

// 对称加密算法提供器
private ICryptoTransform encryptor;     // 加密器对象
private ICryptoTransform decryptor;     // 解密器对象
//public string key = "ABCDEFGHIJKLMNOP";//长度16
//public static byte[] DESKey = new byte[] { 11, 23, 93, 102, 72, 41, 18, 12 };
//public static byte[] DESIV = new byte[] { 75, 158, 46, 97, 78, 57, 17, 36 };
private const int BufferSize = 1024;
public CryptoHelper(string algorithmName, string key)
{
SymmetricAlgorithm provider = SymmetricAlgorithm.Create(algorithmName);
provider.Key = Encoding.UTF8.GetBytes(key);

provider.IV = new byte[] { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

encryptor = provider.CreateEncryptor();
decryptor = provider.CreateDecryptor();
}

public CryptoHelper(string key) : this("TripleDES", key) { }

public MemoryStream EncryptMemoryStream(MemoryStream itemStream)
{
// 创建空的密文流
MemoryStream encryptedStream = new MemoryStream();

CryptoStream cryptoStream =
new CryptoStream(encryptedStream, encryptor, CryptoStreamMode.Write);

// 将明文流写入到buffer中
// 将buffer中的数据写入到cryptoStream中
int bytesRead = 0;
byte[] buffer = new byte[BufferSize];
itemStream.Position = 0;
do
{
bytesRead = itemStream.Read(buffer, 0, BufferSize);
cryptoStream.Write(buffer, 0, bytesRead);
} while (bytesRead > 0);

cryptoStream.FlushFinalBlock();
byte[] buffer2 = encryptedStream.ToArray();
string encryptedText = Convert.ToBase64String(buffer2);
return encryptedStream;
}
public Stream EncryptByte(byte[] data)
{
MemoryStream clearStream = new MemoryStream(data);
clearStream.Position = 0;
// 创建空的密文流
MemoryStream encryptedStream = new MemoryStream();

CryptoStream cryptoStream =
new CryptoStream(encryptedStream, encryptor, CryptoStreamMode.Write);

// 将明文流写入到buffer中
// 将buffer中的数据写入到cryptoStream中
int bytesRead = 0;
byte[] buffer = new byte[BufferSize];
do
{
bytesRead = clearStream.Read(buffer, 0, BufferSize);
cryptoStream.Write(buffer, 0, bytesRead);
} while (bytesRead > 0);
cryptoStream.FlushFinalBlock();
// 获取加密后的文本
byte[] buffer2 = encryptedStream.ToArray();
string encryptedText = Convert.ToBase64String(buffer2);
return encryptedStream;
}

// 加密算法
public string EncryptText(string clearText)
{
// 创建明文流
byte[] clearBuffer = Encoding.UTF8.GetBytes(clearText);
MemoryStream clearStream = new MemoryStream(clearBuffer);

// 创建空的密文流
MemoryStream encryptedStream = new MemoryStream();

CryptoStream cryptoStream =
new CryptoStream(encryptedStream, encryptor, CryptoStreamMode.Write);

// 将明文流写入到buffer中
// 将buffer中的数据写入到cryptoStream中
int bytesRead = 0;
byte[] buffer = new byte[BufferSize];
do
{
bytesRead = clearStream.Read(buffer, 0, BufferSize);
cryptoStream.Write(buffer, 0, bytesRead);
} while (bytesRead > 0);

cryptoStream.FlushFinalBlock();

// 获取加密后的文本
buffer = encryptedStream.ToArray();
string encryptedText = Convert.ToBase64String(buffer);
return encryptedText;
}

public MemoryStream DecryptMemoryStream(MemoryStream encryptedStream)
{
MemoryStream clearStream = new MemoryStream();
CryptoStream cryptoStream =
new CryptoStream(encryptedStream, decryptor, CryptoStreamMode.Read);

int bytesRead = 0;
byte[] buffer = new byte[BufferSize];

do
{
bytesRead = cryptoStream.Read(buffer, 0, BufferSize);
clearStream.Write(buffer, 0, bytesRead);
} while (bytesRead > 0);

buffer = clearStream.GetBuffer();
MemoryStream clearStreamResult = new MemoryStream(buffer);
return clearStreamResult;
}

//
// 解密算法, http://www.51testing.com/html/67/n-220867-4.html // 解密算法
public string DecryptText(string encryptedText)
{
byte[] encryptedBuffer = Convert.FromBase64String(encryptedText);
Stream encryptedStream = new MemoryStream(encryptedBuffer);

MemoryStream clearStream = new MemoryStream();
CryptoStream cryptoStream =
new CryptoStream(encryptedStream, decryptor, CryptoStreamMode.Read);

int bytesRead = 0;
byte[] buffer = new byte[BufferSize];

do
{
bytesRead = cryptoStream.Read(buffer, 0, BufferSize);
clearStream.Write(buffer, 0, bytesRead);
} while (bytesRead > 0);

buffer = clearStream.GetBuffer();
string clearText =
Encoding.UTF8.GetString(buffer, 0, (int)clearStream.Length);

return clearText;
}

public static string Encrypt(string clearText, string key)
{
CryptoHelper helper = new CryptoHelper(key);
return helper.EncryptText(clearText);
}

public static string Decrypt(string encryptedText, string key)
{
CryptoHelper helper = new CryptoHelper(key);
return helper.DecryptText(encryptedText);
}
}
}

// string key="ABCDEFGHIJKLMNOP"; //16位字符串

public byte[] DataSetToBytes(DataSet ds)
{
DESCryptoServiceProvider objDES = new DESCryptoServiceProvider();
MemoryStream dataStream = new MemoryStream();
MemoryStream dataStream2 = new MemoryStream();
ds.WriteXml(dataStream, XmlWriteMode.WriteSchema);

CryptoHelperLib.CryptoHelper cryhelper = new CryptoHelperLib.CryptoHelper(key);
dataStream2= cryhelper.EncryptMemoryStream(dataStream);
byte[] buf = dataStream2.ToArray();

return buf;
}

public DataSet DataSetFromBytes(byte[] buf)
{

MemoryStream dataStream = new MemoryStream(buf);
MemoryStream dataStream2 = new MemoryStream();
CryptoHelperLib.CryptoHelper cryhelper = new CryptoHelperLib.CryptoHelper(key);
dataStream2 = cryhelper.DecryptMemoryStream(dataStream);
dataStream2.Position = 0;
DataSet ds = new DataSet();
ds.ReadXml(dataStream2);
return ds;
}