本文实例讲述了c#通过DES加密算法加密大文件的方法。分享给大家供大家参考。具体实现方法如下:
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Text;
using System.IO;
using System.Security.Cryptography;
public partial class Default2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };//自定义密匙
private string filePathA;//储存文件路径
private string filePathB;//储存文件复制后的路径
/// <summary>
/// 文件加密
/// </summary>
/// <param name="inFile">文件储存路径</param>
/// <param name="outFile">储存文件复制的路径</param>
/// <param name="encryptKey"></param>
/// <returns></returns>
public bool EncryptDES(string inFile, string outFile, string encryptKey)
{
byte[] rgb = Keys;
try
{
byte[] rgbKeys = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
FileStream inFs = new FileStream(inFile, FileMode.Open, FileAccess.Read);//读入流
FileStream outFs = new FileStream(outFile, FileMode.OpenOrCreate, FileAccess.Write);// 等待写入流
outFs.SetLength(0);//帮助读写的变量
byte[] byteIn = new byte[100];//放临时读入的流
long readLen = 0;//读入流的长度
long totalLen = inFs.Length;//读入流的总长度
int everylen=0;//每次读入流的长度
DES des = new DESCryptoServiceProvider();//将inFile加密后放到outFile
CryptoStream encStream = new CryptoStream(outFs, des.CreateEncryptor(rgb, rgbKeys), CryptoStreamMode.Write);
while (readLen < totalLen)
{
everylen = inFs.Read(byteIn, 0, 100);
encStream.Write(byteIn, 0, everylen);
readLen = readLen + everylen;
}
encStream.Close();
inFs.Close();
outFs.Close();
return true;//加密成功
}
catch (Exception ex)
{
Response.Write(ex.Message.ToString());
return false;//加密失败
}
}
public bool DecryptDES(string inFile, string outFile, string encryptKey)
{
byte[] rgb = Keys;
try
{
byte[] rgbKeys = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
FileStream inFs = new FileStream(inFile, FileMode.Open, FileAccess.Read);//读入流
FileStream outFs = new FileStream(outFile, FileMode.OpenOrCreate, FileAccess.Write);// 等待写入流
outFs.SetLength(0);//帮助读写的变量
byte[] byteIn = new byte[100];//放临时读入的流
long readLen = 0;//读入流的长度
long totalLen = inFs.Length;//读入流的总长度
int everylen=0;//每次读入流的长度
DES des = new DESCryptoServiceProvider();//将inFile加密后放到outFile
CryptoStream encStream = new CryptoStream(outFs, des.CreateDecryptor(rgb, rgbKeys), CryptoStreamMode.Write);
while (readLen < totalLen)
{
everylen = inFs.Read(byteIn, 0, 100);
encStream.Write(byteIn, 0, everylen);
readLen = readLen + everylen;
}
encStream.Close();
inFs.Close();
outFs.Close();
return true;//加密成功
}
catch (Exception ex)
{
Response.Write(ex.Message.ToString());
return false;//加密失败
}
}
/// <summary>
/// 拷贝文件
/// </summary>
public void copyFile()
{
filePathA = this.fei.PostedFile.FileName;//获取文件全部路径
string fileName = this.fei.FileName;
string path = System.IO.Path.GetDirectoryName(filePathA);
filePathB = path + "\\1" + fileName;//重新设置文件名
File.Copy(filePathA, filePathB);
}
protected void btnOK_Click(object sender, EventArgs e)
{
copyFile();
if (EncryptDES(filePathB, filePathA, "mingrisoft"))
{
RegisterStartupScript("false", "<script>alert('加密成功!\\n');</script>");
}
else
{
RegisterStartupScript("false", "<script>alert('失败成功!\\n');</script>");
}
File.Delete(filePathB);
}
protected void btnCancel_Click(object sender, EventArgs e)
{
copyFile();
if (DecryptDES(filePathB, filePathA, "mingrisoft"))
{
RegisterStartupScript("false", "<script>alert('加密成功!\\n');</script>");
}
else
{
RegisterStartupScript("false", "<script>alert('失败成功!\\n');</script>");
}
File.Delete(filePathB);
}
}
希望本文所述对大家的C#程序设计有所帮助。
您可能感兴趣的文章:C#的3DES加密解密算法实例代码C#编写DES加密、解密类des加密解密源码 C# key值问题分析php实现和c#一致的DES加密解密实例C#使用DES和AES实现加密解密功能示例C# 3DES加密详解C# DES加密算法中向量的作用详细解析C#实现对AES加密和解密的方法基于C#对用户密码使用MD5加密与解密asp实现的sha1加密解密代码(和C#兼容)C#编写的Base64加密和解密类C#实现简单的3DES加密解密功能示例