C#加密解密算法

1、方法一 (不可逆加密)

 

 

public string EncryptPassword(string PasswordString,string PasswordFormat ) 
   

   
string  encryptPassword = null;
   
if (PasswordFormat="SHA1")
   encryptPassword
=FormsAuthortication.HashPasswordForStoringInConfigFile(PasswordString 

,
"SHA1"); 
   }
 
   elseif (PasswordFormat
="MD5"
   
{ encryptPassword=FormsAuthortication.HashPasswordForStoringInConfigFile(PasswordString 

,
"MD5"); 
   }

return encryptPassword ;
}

 

2、方法二 (可逆加密)

 

    
public interface IBindesh
{
    
string encode(string str);
    
string decode(string str);
}


public class EncryptionDecryption : IBindesh
    
{
        
public string encode(string str)
        
{
            
string htext = ""

            
for ( int i = 0; i < str.Length; i++)
            
{
                htext 
= htext + (char) (str[i] + 10 - 1 * 2);
            }

            
return htext;
        }


        
public string decode(string str)
        
{
            
string dtext = ""

            
for ( int i=0; i < str.Length; i++)
            
{
                dtext 
= dtext + (char) (str[i] - 10 + 1*2);
            }

            
return dtext;
        }


 

3、方法三 (可逆加密)

 

        
        
const string KEY_64 = "VavicApp";//注意了,是8个字符,64位

        
const string IV_64 = "VavicApp"
public string Encode(string data)
        
{
            
byte[] byKey = System.Text.ASCIIEncoding.ASCII.GetBytes(KEY_64);
            
byte[] byIV = System.Text.ASCIIEncoding.ASCII.GetBytes(IV_64);

            DESCryptoServiceProvider cryptoProvider 
= new DESCryptoServiceProvider();
            
int i = cryptoProvider.KeySize;
            MemoryStream ms 
= new MemoryStream();
            CryptoStream cst 
= new CryptoStream(ms, cryptoProvider.CreateEncryptor(byKey, 

byIV), CryptoStreamMode.Write);

            StreamWriter sw 
= new StreamWriter(cst);
            sw.Write(data);
            sw.Flush();
            cst.FlushFinalBlock();
            sw.Flush();
            
return Convert.ToBase64String(ms.GetBuffer(), 0, (int)ms.Length);

        }


        
public string Decode(string data)
        
{
            
byte[] byKey = System.Text.ASCIIEncoding.ASCII.GetBytes(KEY_64);
            
byte[] byIV = System.Text.ASCIIEncoding.ASCII.GetBytes(IV_64);

            
byte[] byEnc;
            
try
            
{
                byEnc 
= Convert.FromBase64String(data);
            }

            
catch
            
{
                
return null;
            }


            DESCryptoServiceProvider cryptoProvider 
= new DESCryptoServiceProvider();
            MemoryStream ms 
= new MemoryStream(byEnc);
            CryptoStream cst 
= new CryptoStream(ms, cryptoProvider.CreateDecryptor(byKey, 

byIV), CryptoStreamMode.Read);
            StreamReader sr 
= new StreamReader(cst);
            
return sr.ReadToEnd();
        }

 

4、MD5不可逆加密

    (32位加密)

public string GetMD5(string s, string _input_charset)
    
{

        
/**//// <summary>
        
/// 与ASP兼容的MD5加密算法
        
/// </summary>


        MD5 md5 
= new MD5CryptoServiceProvider();
        
byte[] t = md5.ComputeHash(Encoding.GetEncoding(_input_charset).GetBytes(s));
        StringBuilder sb 
= new StringBuilder(32);
        
for (int i = 0; i < t.Length; i++)
        
{
            sb.Append(t[i].ToString(
"x").PadLeft(2, '0'));
        }

        
return sb.ToString();
    }

   (16位加密)

 

public static string GetMd5Str(string ConvertString)
    
{
        MD5CryptoServiceProvider md5 
= new MD5CryptoServiceProvider();
        
string t2 = 

BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(ConvertString)), 
48);
        t2 
= t2.Replace("-""");
        
return t2;
    }
 
 

5、加解文本文件

 

    
//加密文件
    private static void EncryptData(String inName, String outName, byte[] desKey, byte[] 

desIV)
    
{
        
//Create the file streams to handle the input and output files.
        FileStream fin = new FileStream(inName, FileMode.Open, FileAccess.Read);
        FileStream fout 
= new FileStream(outName, FileMode.OpenOrCreate, FileAccess.Write);
        fout.SetLength(
0);

        
//Create variables to help with read and write.
        byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
        long rdlen = 0;              //This is the total number of bytes written.
        long totlen = fin.Length;    //This is the total length of the input file.
        int len;                     //This is the number of bytes to be written at a time.

        DES des 
= new DESCryptoServiceProvider();
        CryptoStream encStream 
= new CryptoStream(fout, des.CreateEncryptor(desKey, desIV), 

CryptoStreamMode.Write);

        
//Read from the input file, then encrypt and write to the output file.
        while (rdlen < totlen)
        
{
            len 
= fin.Read(bin, 0100);
            encStream.Write(bin, 
0, len);
            rdlen 
= rdlen + len;
        }


        encStream.Close();
        fout.Close();
        fin.Close();
    }


    
//解密文件
    private static void DecryptData(String inName, String outName, byte[] desKey, byte[] 

desIV)
    
{
        
//Create the file streams to handle the input and output files.
        FileStream fin = new FileStream(inName, FileMode.Open, FileAccess.Read);
        FileStream fout 
= new FileStream(outName, FileMode.OpenOrCreate, FileAccess.Write);
        fout.SetLength(
0);

        
//Create variables to help with read and write.
        byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
        long rdlen = 0;              //This is the total number of bytes written.
        long totlen = fin.Length;    //This is the total length of the input file.
        int len;                     //This is the number of bytes to be written at a time.

        DES des 
= new DESCryptoServiceProvider();
        CryptoStream encStream 
= new CryptoStream(fout, des.CreateDecryptor(desKey, desIV), 

CryptoStreamMode.Write);

        
//Read from the input file, then encrypt and write to the output file.
        while (rdlen < totlen)
        
{
            len 
= fin.Read(bin, 0100);
            encStream.Write(bin, 
0, len);
            rdlen 
= rdlen + len;
        }


        encStream.Close();
        fout.Close();
        fin.Close();
    }

 

6

using System;
using System.Collections.Generic;
using System.Text;
using System.Security.Cryptography;
using System.IO;

namespace Component
{
    
public class Security
    
{
        
public Security()
        

        
        }


        
//默认密钥向量
        private static byte[] Keys = 0x120x340x560x780x900xAB0xCD0xEF };
        
/**//**//**//// <summary>
        
/// DES加密字符串
        
/// </summary>
        
/// <param name="encryptString">待加密的字符串</param>
        
/// <param name="encryptKey">加密密钥,要求为8位</param>
        
/// <returns>加密成功返回加密后的字符串,失败返回源串</returns>

        public static string EncryptDES(string encryptString, string encryptKey)
        
{
            
try
            
{
                
byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(08));
                
byte[] rgbIV = Keys;
                
byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                DESCryptoServiceProvider dCSP 
= new DESCryptoServiceProvider();
                MemoryStream mStream 
= new MemoryStream();
                CryptoStream cStream 
= new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, 

rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 
0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                
return Convert.ToBase64String(mStream.ToArray());
            }

            
catch
            
{
                
return encryptString;
            }

        }


        
/**//**//**//// <summary>
        
/// DES解密字符串
        
/// </summary>
        
/// <param name="decryptString">待解密的字符串</param>
        
/// <param name="decryptKey">解密密钥,要求为8位,和加密密钥相同</param>
        
/// <returns>解密成功返回解密后的字符串,失败返源串</returns>

        public static string DecryptDES(string decryptString, string decryptKey)
        
{
            
try
            
{
                
byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey);
                
byte[] rgbIV = Keys;
                
byte[] inputByteArray = Convert.FromBase64String(decryptString);
                DESCryptoServiceProvider DCSP 
= new DESCryptoServiceProvider();
                MemoryStream mStream 
= new MemoryStream();
                CryptoStream cStream 
= new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, 

rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 
0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                
return Encoding.UTF8.GetString(mStream.ToArray());
            }

            
catch
            
{
                
return decryptString;
            }

        }
 


    }

}

转自http://www.cnblogs.com/yiki/archive/2007/08/28/872373.html

原文地址:https://www.cnblogs.com/yanluckly/p/1407777.html