C# 基于密钥的64位加密与解密方法(原创)

本程序适用于产品的价格加密生成图片格式的价格，防止价格被抓去

using System;

///

/// TTBase64Encode 的摘要说明
///

public class TTBase64Encode
{
public TTBase64Encode()
{
//
// TODO: 在此处添加构造函数逻辑
//
}

const string imgurlhost = " http://img.cblogs.com " ;
const string ttBASE_64_MAP_INIT = " ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/ " ;
// ReadKeyFromFile(g_KeyLocation)
const string g_Key = " WERTYUIOFVGBNM663285716 " ;

string ttnewline;

string [] ttBase64EncMap = new string [ 63 ];
string [] Base64DecMap = new string [ 127 ];

// 初始化函数
public void ttinitCodecs()
{
// 初始化变量
ttnewline = "

" + Convert.ToChar( 13 ) + Convert.ToChar( 10 );
dynamic ttmax = null ;
dynamic ttidx = null ;
ttmax = ttBASE_64_MAP_INIT.Length;

for (ttidx = 0 ; ttidx <= ttmax - 1 ; ttidx ++ )
{
ttBase64EncMap[ttidx] = ttBASE_64_MAP_INIT.Substring(ttidx + 1 , 1 );
}
for (ttidx = 0 ; ttidx <= ttmax - 1 ; ttidx ++ )
{

Base64DecMap[Asc(ttBase64EncMap[ttidx])] = ttidx;
}
}

///

/// 转化为ascii
///

///
///
protected int stringtoascii( string s)
{
string ascii = "" ;
foreach ( char c in s)
{
int str = ( int )c;
ascii += str + " , " ;
} if (ascii.Length > 0 )
{
ascii = ascii.Substring( 0 , ascii.Length - 1 );
}
return Convert.ToInt32(ascii);
}
///

/// 转化为Ascii
///

///
///
public static int Asc( string character)
{
if (character.Length == 1 )
{
System.Text.ASCIIEncoding asciiEncoding = new System.Text.ASCIIEncoding();
int intAsciiCode = ( int )asciiEncoding.GetBytes(character)[ 0 ];
return (intAsciiCode);
}
else
{
throw new Exception( " Character is not valid. " );
}
}

/// Base64加密函数
public object ttbase64Encode( string price)
{
string ttret = string .Empty;
if (price.Length == 0 )
{
return "" ;
}

string ttplain = EnCrypt(price).ToString();


dynamic ttndx = null ;
dynamic ttby3 = null ;
dynamic ttfirst = null ;
dynamic ttsecond = null ;
dynamic ttthird = null ;
ttby3 = (ttplain.Length / 3 ) * 3 ;
ttndx = 1 ;
while (ttndx <= ttby3)
{

ttfirst = Asc(ttplain.Substring(ttndx + 0 , 1 ));
ttsecond = Asc(ttplain.Substring(ttndx + 1 , 1 ));
ttthird = Asc(ttplain.Substring(ttndx + 2 , 1 ));
ttret = ttret + ttBase64EncMap[(ttfirst / 4 ) & 63 ];
ttret = ttret + ttBase64EncMap[((ttfirst * 16 ) & 48 ) + ((ttsecond / 16 ) & 15 )];
ttret = ttret + ttBase64EncMap[((ttsecond * 4 ) & 60 ) + ((ttthird / 64 ) & 3 )];
ttret = ttret + ttBase64EncMap[ttthird & 63 ];
ttndx = ttndx + 3 ;
}

if (ttby3 < ttplain.Length)
{

ttfirst = Asc(ttplain.Substring(ttndx + 0 , 1 ));
ttret = ttret + ttBase64EncMap[(ttfirst / 4 ) & 63 ];
if ((ttplain.Length % 3 ) == 2 )
{

ttsecond = Asc(ttplain.Substring(ttndx + 1 , 1 ));
ttret = ttret + ttBase64EncMap[((ttfirst * 16 ) & 48 ) + ((ttsecond / 16 ) & 15 )];
ttret = ttret + ttBase64EncMap[((ttsecond * 4 ) & 60 )];
}
else
{
ttret = ttret + ttBase64EncMap[(ttfirst * 16 ) & 48 ];
}
}

return ttret;
}
/// /Base64解密函数
public object ttbase64Decode( string ttscrambled)
{
string ttret = string .Empty;
if (ttscrambled.Length == 0 )
{
return ttret;
}
dynamic ttrealLen = null ;
ttrealLen = ttscrambled.Length;
while (ttscrambled.Substring(ttrealLen, 1 ) == " = " )
{
ttrealLen = ttrealLen - 1 ;
}

dynamic ttndx = null ;
dynamic ttby4 = null ;
dynamic ttfirst = null ;
dynamic ttsecond = null ;
dynamic ttthird = null ;
dynamic ttfourth = null ;
ttret = "" ;
ttby4 = (ttrealLen / 4 ) * 4 ;
ttndx = 1 ;

while (ttndx <= ttby4)
{
ttfirst = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 0 , 1 ))];
ttsecond = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 1 , 1 ))];
ttthird = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 2 , 1 ))];
ttfourth = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 3 , 1 ))];

ttret = ttret + Convert.ToChar(((ttfirst * 4 ) & 255 ) + ((ttsecond / 16 ) & 3 ));
ttret = ttret + Convert.ToChar(((ttsecond * 16 ) & 255 ) + ((ttthird / 4 ) & 15 ));
ttret = ttret + Convert.ToChar(((ttthird * 64 ) & 255 ) + (ttfourth & 63 ));
ttndx = ttndx + 4 ;
}
if (ttndx < ttrealLen)
{
ttfirst = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 0 , 1 ))];
ttsecond = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 1 , 1 ))];
ttret = ttret + Convert.ToChar(((ttfirst * 4 ) & 255 ) + ((ttsecond / 16 ) & 3 ));
if (ttrealLen % 4 == 3 )
{
ttthird = Base64DecMap[Asc(ttscrambled.Substring(ttndx + 2 , 1 ))];
ttret = ttret + Convert.ToChar(((ttsecond * 16 ) & 255 ) + ((ttthird / 4 ) & 15 ));
}
}

return ttret;
}

///

/// 加密调用方法入口
///

///
///
public object EnCrypt( string strCryptThis)
{
dynamic strChar = null ;
dynamic iKeyChar = null ;
dynamic iStringChar = null ;
dynamic strEncrypted = null ;
dynamic I = null ;
dynamic leng = null ;
leng = strCryptThis.Length;

for (I = 0 ; I < leng; I ++ )
{
iKeyChar = Asc(g_Key.Substring(I, 1 ));
iStringChar = Asc(strCryptThis.Substring(I, 1 ));
dynamic iCryptChar = iKeyChar ^ iStringChar;
strEncrypted += Convert.ToChar(iCryptChar).ToString();
}
return strEncrypted;

}

}

转载于:https://www.cnblogs.com/jqbird/archive/2011/03/16/1986096.html