JS实现的3des+base64加密解密算法完整示例

2019-11-19 13:48:58

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本文实例讲述了JS实现的3des+base64加密解密算法。分享给大家供大家参考，具体如下：

1. index.html：

<html xmlns="http://www.w3.org/1999/xhtml"><head>  <title>www.VeVB.COm BASE64编码</title>  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />  <script type="text/javascript" src="Base64.js"></script>  <script type="text/javascript" src="DES3.js"></script></head><body><script type="text/javascript">var str = "网址：//www.VeVB.COm";document.write("原始字符串:</br>"+str);var base64 = BASE64.encoder(str);//返回编码后的字符document.write("</br>BASE64后:</br>"+base64);//alert(base64);var unicode= BASE64.decoder(base64);//返回会解码后的字符串。//alert(unicode);document.write("</br>还原:</br>"+unicode);//var str= "你好123hello";var key = "qXSdHWfbSZaaLeHBRhLgxBiG";//alert(decrypt_3des);var des3en = DES3.encrypt(key,str);document.write("</br>des3加密:</br>"+des3en);document.write("</br>des3解密:</br>"+DES3.decrypt(key,des3en));</script></body>

2. DES3.js文件：

/**  * DES 加密算法  *  * 该函数接受一个 8 字节字符串作为普通 DES 算法的密钥（也就是 64 位，但是算法只使用 56 位），或者接受一个 24 字节字符串作为 3DES  * 算法的密钥；第二个参数是要加密或解密的信息字符串；第三个布尔值参数用来说明信息是加密还是解密；接下来的可选参数 mode 如果是 0 表示 ECB  * 模式，1 表示 CBC 模式，默认是 ECB 模式；最后一个可选项是一个 8 字节的输入向量字符串（在 ECB 模式下不使用）。返回的密文是字符串。  *  * 参数： <br>  * key: 8字节字符串作为普通 DES 算法的密钥,或 24 字节字符串作为 3DES <br>  * message： 加密或解密的信息字符串<br>  * encrypt: 布尔值参数用来说明信息是加密还是解密<br>  * mode: 1:CBC模式，0:ECB模式(默认)<br>  * iv:<br>  * padding: 可选项, 8字节的输入向量字符串（在 ECB 模式下不使用）  *///this takes the key, the message, and whether to encrypt or decryptfunction des (key, message, encrypt, mode, iv, padding) {  if(encrypt) //如果是加密的话，首先转换编码    message = unescape(encodeURIComponent(message));  //declaring this locally speeds things up a bit  var spfunction1 = new Array (0x1010400,0,0x10000,0x1010404,0x1010004,0x10404,0x4,0x10000,0x400,0x1010400,0x1010404,0x400,0x1000404,0x1010004,0x1000000,0x4,0x404,0x1000400,0x1000400,0x10400,0x10400,0x1010000,0x1010000,0x1000404,0x10004,0x1000004,0x1000004,0x10004,0,0x404,0x10404,0x1000000,0x10000,0x1010404,0x4,0x1010000,0x1010400,0x1000000,0x1000000,0x400,0x1010004,0x10000,0x10400,0x1000004,0x400,0x4,0x1000404,0x10404,0x1010404,0x10004,0x1010000,0x1000404,0x1000004,0x404,0x10404,0x1010400,0x404,0x1000400,0x1000400,0,0x10004,0x10400,0,0x1010004);  var spfunction2 = new Array (-0x7fef7fe0,-0x7fff8000,0x8000,0x108020,0x100000,0x20,-0x7fefffe0,-0x7fff7fe0,-0x7fffffe0,-0x7fef7fe0,-0x7fef8000,-0x80000000,-0x7fff8000,0x100000,0x20,-0x7fefffe0,0x108000,0x100020,-0x7fff7fe0,0,-0x80000000,0x8000,0x108020,-0x7ff00000,0x100020,-0x7fffffe0,0,0x108000,0x8020,-0x7fef8000,-0x7ff00000,0x8020,0,0x108020,-0x7fefffe0,0x100000,-0x7fff7fe0,-0x7ff00000,-0x7fef8000,0x8000,-0x7ff00000,-0x7fff8000,0x20,-0x7fef7fe0,0x108020,0x20,0x8000,-0x80000000,0x8020,-0x7fef8000,0x100000,-0x7fffffe0,0x100020,-0x7fff7fe0,-0x7fffffe0,0x100020,0x108000,0,-0x7fff8000,0x8020,-0x80000000,-0x7fefffe0,-0x7fef7fe0,0x108000);  var spfunction3 = new Array (0x208,0x8020200,0,0x8020008,0x8000200,0,0x20208,0x8000200,0x20008,0x8000008,0x8000008,0x20000,0x8020208,0x20008,0x8020000,0x208,0x8000000,0x8,0x8020200,0x200,0x20200,0x8020000,0x8020008,0x20208,0x8000208,0x20200,0x20000,0x8000208,0x8,0x8020208,0x200,0x8000000,0x8020200,0x8000000,0x20008,0x208,0x20000,0x8020200,0x8000200,0,0x200,0x20008,0x8020208,0x8000200,0x8000008,0x200,0,0x8020008,0x8000208,0x20000,0x8000000,0x8020208,0x8,0x20208,0x20200,0x8000008,0x8020000,0x8000208,0x208,0x8020000,0x20208,0x8,0x8020008,0x20200);  var spfunction4 = new Array (0x802001,0x2081,0x2081,0x80,0x802080,0x800081,0x800001,0x2001,0,0x802000,0x802000,0x802081,0x81,0,0x800080,0x800001,0x1,0x2000,0x800000,0x802001,0x80,0x800000,0x2001,0x2080,0x800081,0x1,0x2080,0x800080,0x2000,0x802080,0x802081,0x81,0x800080,0x800001,0x802000,0x802081,0x81,0,0,0x802000,0x2080,0x800080,0x800081,0x1,0x802001,0x2081,0x2081,0x80,0x802081,0x81,0x1,0x2000,0x800001,0x2001,0x802080,0x800081,0x2001,0x2080,0x800000,0x802001,0x80,0x800000,0x2000,0x802080);  var spfunction5 = new Array (0x100,0x2080100,0x2080000,0x42000100,0x80000,0x100,0x40000000,0x2080000,0x40080100,0x80000,0x2000100,0x40080100,0x42000100,0x42080000,0x80100,0x40000000,0x2000000,0x40080000,0x40080000,0,0x40000100,0x42080100,0x42080100,0x2000100,0x42080000,0x40000100,0,0x42000000,0x2080100,0x2000000,0x42000000,0x80100,0x80000,0x42000100,0x100,0x2000000,0x40000000,0x2080000,0x42000100,0x40080100,0x2000100,0x40000000,0x42080000,0x2080100,0x40080100,0x100,0x2000000,0x42080000,0x42080100,0x80100,0x42000000,0x42080100,0x2080000,0,0x40080000,0x42000000,0x80100,0x2000100,0x40000100,0x80000,0,0x40080000,0x2080100,0x40000100);  var spfunction6 = new Array (0x20000010,0x20400000,0x4000,0x20404010,0x20400000,0x10,0x20404010,0x400000,0x20004000,0x404010,0x400000,0x20000010,0x400010,0x20004000,0x20000000,0x4010,0,0x400010,0x20004010,0x4000,0x404000,0x20004010,0x10,0x20400010,0x20400010,0,0x404010,0x20404000,0x4010,0x404000,0x20404000,0x20000000,0x20004000,0x10,0x20400010,0x404000,0x20404010,0x400000,0x4010,0x20000010,0x400000,0x20004000,0x20000000,0x4010,0x20000010,0x20404010,0x404000,0x20400000,0x404010,0x20404000,0,0x20400010,0x10,0x4000,0x20400000,0x404010,0x4000,0x400010,0x20004010,0,0x20404000,0x20000000,0x400010,0x20004010);  var spfunction7 = new Array (0x200000,0x4200002,0x4000802,0,0x800,0x4000802,0x200802,0x4200800,0x4200802,0x200000,0,0x4000002,0x2,0x4000000,0x4200002,0x802,0x4000800,0x200802,0x200002,0x4000800,0x4000002,0x4200000,0x4200800,0x200002,0x4200000,0x800,0x802,0x4200802,0x200800,0x2,0x4000000,0x200800,0x4000000,0x200800,0x200000,0x4000802,0x4000802,0x4200002,0x4200002,0x2,0x200002,0x4000000,0x4000800,0x200000,0x4200800,0x802,0x200802,0x4200800,0x802,0x4000002,0x4200802,0x4200000,0x200800,0,0x2,0x4200802,0,0x200802,0x4200000,0x800,0x4000002,0x4000800,0x800,0x200002);  var spfunction8 = new Array (0x10001040,0x1000,0x40000,0x10041040,0x10000000,0x10001040,0x40,0x10000000,0x40040,0x10040000,0x10041040,0x41000,0x10041000,0x41040,0x1000,0x40,0x10040000,0x10000040,0x10001000,0x1040,0x41000,0x40040,0x10040040,0x10041000,0x1040,0,0,0x10040040,0x10000040,0x10001000,0x41040,0x40000,0x41040,0x40000,0x10041000,0x1000,0x40,0x10040040,0x1000,0x41040,0x10001000,0x40,0x10000040,0x10040000,0x10040040,0x10000000,0x40000,0x10001040,0,0x10041040,0x40040,0x10000040,0x10040000,0x10001000,0x10001040,0,0x10041040,0x41000,0x41000,0x1040,0x1040,0x40040,0x10000000,0x10041000);  //create the 16 or 48 subkeys we will need  var keys = des_createKeys (key);  var m=0, i, j, temp, temp2, right1, right2, left, right, looping;  var cbcleft, cbcleft2, cbcright, cbcright2  var endloop, loopinc;  var len = message.length;  var chunk = 0;  //set up the loops for single and triple des  var iterations = keys.length == 32 ? 3 : 9; //single or triple des  if (iterations == 3) {looping = encrypt ? new Array (0, 32, 2) : new Array (30, -2, -2);}  else {looping = encrypt ? new Array (0, 32, 2, 62, 30, -2, 64, 96, 2) : new Array (94, 62, -2, 32, 64, 2, 30, -2, -2);}  //pad the message depending on the padding parameter  if (padding == 2) message += "    "; //pad the message with spaces  else if (padding == 1) {    if(encrypt) {      temp = 8-(len%8);      message += String.fromCharCode(temp,temp,temp,temp,temp,temp,temp,temp);      if (temp===8) len+=8;    }  } //PKCS7 padding  else if (!padding) message += "/0/0/0/0/0/0/0/0"; //pad the message out with null bytes  //store the result here  var result = "";  var tempresult = "";  if (mode == 1) { //CBC mode    cbcleft = (iv.charCodeAt(m++) << 24) | (iv.charCodeAt(m++) << 16) | (iv.charCodeAt(m++) << 8) | iv.charCodeAt(m++);    cbcright = (iv.charCodeAt(m++) << 24) | (iv.charCodeAt(m++) << 16) | (iv.charCodeAt(m++) << 8) | iv.charCodeAt(m++);    m=0;  }  //loop through each 64 bit chunk of the message  while (m < len) {    left = (message.charCodeAt(m++) << 24) | (message.charCodeAt(m++) << 16) | (message.charCodeAt(m++) << 8) | message.charCodeAt(m++);    right = (message.charCodeAt(m++) << 24) | (message.charCodeAt(m++) << 16) | (message.charCodeAt(m++) << 8) | message.charCodeAt(m++);    //for Cipher Block Chaining mode, xor the message with the previous result    if (mode == 1) {if (encrypt) {left ^= cbcleft; right ^= cbcright;} else {cbcleft2 = cbcleft; cbcright2 = cbcright; cbcleft = left; cbcright = right;}}    //first each 64 but chunk of the message must be permuted according to IP    temp = ((left >>> 4) ^ right) & 0x0f0f0f0f; right ^= temp; left ^= (temp << 4);    temp = ((left >>> 16) ^ right) & 0x0000ffff; right ^= temp; left ^= (temp << 16);    temp = ((right >>> 2) ^ left) & 0x33333333; left ^= temp; right ^= (temp << 2);    temp = ((right >>> 8) ^ left) & 0x00ff00ff; left ^= temp; right ^= (temp << 8);    temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1);    left = ((left << 1) | (left >>> 31));    right = ((right << 1) | (right >>> 31));    //do this either 1 or 3 times for each chunk of the message    for (j=0; j<iterations; j+=3) {      endloop = looping[j+1];      loopinc = looping[j+2];      //now go through and perform the encryption or decryption      for (i=looping[j]; i!=endloop; i+=loopinc) { //for efficiency        right1 = right ^ keys[i];        right2 = ((right >>> 4) | (right << 28)) ^ keys[i+1];        //the result is attained by passing these bytes through the S selection functions        temp = left;        left = right;        right = temp ^ (spfunction2[(right1 >>> 24) & 0x3f] | spfunction4[(right1 >>> 16) & 0x3f]          | spfunction6[(right1 >>> 8) & 0x3f] | spfunction8[right1 & 0x3f]          | spfunction1[(right2 >>> 24) & 0x3f] | spfunction3[(right2 >>> 16) & 0x3f]          | spfunction5[(right2 >>> 8) & 0x3f] | spfunction7[right2 & 0x3f]);      }      temp = left; left = right; right = temp; //unreverse left and right    } //for either 1 or 3 iterations    //move then each one bit to the right    left = ((left >>> 1) | (left << 31));    right = ((right >>> 1) | (right << 31));    //now perform IP-1, which is IP in the opposite direction    temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1);    temp = ((right >>> 8) ^ left) & 0x00ff00ff; left ^= temp; right ^= (temp << 8);    temp = ((right >>> 2) ^ left) & 0x33333333; left ^= temp; right ^= (temp << 2);    temp = ((left >>> 16) ^ right) & 0x0000ffff; right ^= temp; left ^= (temp << 16);    temp = ((left >>> 4) ^ right) & 0x0f0f0f0f; right ^= temp; left ^= (temp << 4);    //for Cipher Block Chaining mode, xor the message with the previous result    if (mode == 1) {if (encrypt) {cbcleft = left; cbcright = right;} else {left ^= cbcleft2; right ^= cbcright2;}}    tempresult += String.fromCharCode ((left>>>24), ((left>>>16) & 0xff), ((left>>>8) & 0xff), (left & 0xff), (right>>>24), ((right>>>16) & 0xff), ((right>>>8) & 0xff), (right & 0xff));    chunk += 8;    if (chunk == 512) {result += tempresult; tempresult = ""; chunk = 0;}  } //for every 8 characters, or 64 bits in the message  //return the result as an array  result += tempresult;  result = result.replace(//0*$/g, "");  if(!encrypt ) { //如果是解密的话，解密结束后对PKCS7 padding进行解码，并转换成utf-8编码    if(padding === 1) { //PKCS7 padding解码      var len = result.length, paddingChars = 0;      len && (paddingChars = result.charCodeAt(len-1));      (paddingChars <= 8) && (result = result.substring(0, len - paddingChars));    }    //转换成UTF-8编码    result = decodeURIComponent(escape(result));  }  return result;} //end of des//des_createKeys//this takes as input a 64 bit key (even though only 56 bits are used)//as an array of 2 integers, and returns 16 48 bit keysfunction des_createKeys (key) {  //declaring this locally speeds things up a bit  var pc2bytes0 = new Array (0,0x4,0x20000000,0x20000004,0x10000,0x10004,0x20010000,0x20010004,0x200,0x204,0x20000200,0x20000204,0x10200,0x10204,0x20010200,0x20010204);  var pc2bytes1 = new Array (0,0x1,0x100000,0x100001,0x4000000,0x4000001,0x4100000,0x4100001,0x100,0x101,0x100100,0x100101,0x4000100,0x4000101,0x4100100,0x4100101);  var pc2bytes2 = new Array (0,0x8,0x800,0x808,0x1000000,0x1000008,0x1000800,0x1000808,0,0x8,0x800,0x808,0x1000000,0x1000008,0x1000800,0x1000808);  var pc2bytes3 = new Array (0,0x200000,0x8000000,0x8200000,0x2000,0x202000,0x8002000,0x8202000,0x20000,0x220000,0x8020000,0x8220000,0x22000,0x222000,0x8022000,0x8222000);  var pc2bytes4 = new Array (0,0x40000,0x10,0x40010,0,0x40000,0x10,0x40010,0x1000,0x41000,0x1010,0x41010,0x1000,0x41000,0x1010,0x41010);  var pc2bytes5 = new Array (0,0x400,0x20,0x420,0,0x400,0x20,0x420,0x2000000,0x2000400,0x2000020,0x2000420,0x2000000,0x2000400,0x2000020,0x2000420);  var pc2bytes6 = new Array (0,0x10000000,0x80000,0x10080000,0x2,0x10000002,0x80002,0x10080002,0,0x10000000,0x80000,0x10080000,0x2,0x10000002,0x80002,0x10080002);  var pc2bytes7 = new Array (0,0x10000,0x800,0x10800,0x20000000,0x20010000,0x20000800,0x20010800,0x20000,0x30000,0x20800,0x30800,0x20020000,0x20030000,0x20020800,0x20030800);  var pc2bytes8 = new Array (0,0x40000,0,0x40000,0x2,0x40002,0x2,0x40002,0x2000000,0x2040000,0x2000000,0x2040000,0x2000002,0x2040002,0x2000002,0x2040002);  var pc2bytes9 = new Array (0,0x10000000,0x8,0x10000008,0,0x10000000,0x8,0x10000008,0x400,0x10000400,0x408,0x10000408,0x400,0x10000400,0x408,0x10000408);  var pc2bytes10 = new Array (0,0x20,0,0x20,0x100000,0x100020,0x100000,0x100020,0x2000,0x2020,0x2000,0x2020,0x102000,0x102020,0x102000,0x102020);  var pc2bytes11 = new Array (0,0x1000000,0x200,0x1000200,0x200000,0x1200000,0x200200,0x1200200,0x4000000,0x5000000,0x4000200,0x5000200,0x4200000,0x5200000,0x4200200,0x5200200);  var pc2bytes12 = new Array (0,0x1000,0x8000000,0x8001000,0x80000,0x81000,0x8080000,0x8081000,0x10,0x1010,0x8000010,0x8001010,0x80010,0x81010,0x8080010,0x8081010);  var pc2bytes13 = new Array (0,0x4,0x100,0x104,0,0x4,0x100,0x104,0x1,0x5,0x101,0x105,0x1,0x5,0x101,0x105);  //how many iterations (1 for des, 3 for triple des)  var iterations = key.length > 8 ? 3 : 1; //changed by Paul 16/6/2007 to use Triple DES for 9+ byte keys  //stores the return keys  var keys = new Array (32 * iterations);  //now define the left shifts which need to be done  var shifts = new Array (0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0);  //other variables  var lefttemp, righttemp, m=0, n=0, temp;  for (var j=0; j<iterations; j++) { //either 1 or 3 iterations    var left = (key.charCodeAt(m++) << 24) | (key.charCodeAt(m++) << 16) | (key.charCodeAt(m++) << 8) | key.charCodeAt(m++);    var right = (key.charCodeAt(m++) << 24) | (key.charCodeAt(m++) << 16) | (key.charCodeAt(m++) << 8) | key.charCodeAt(m++);    temp = ((left >>> 4) ^ right) & 0x0f0f0f0f; right ^= temp; left ^= (temp << 4);    temp = ((right >>> -16) ^ left) & 0x0000ffff; left ^= temp; right ^= (temp << -16);    temp = ((left >>> 2) ^ right) & 0x33333333; right ^= temp; left ^= (temp << 2);    temp = ((right >>> -16) ^ left) & 0x0000ffff; left ^= temp; right ^= (temp << -16);    temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1);    temp = ((right >>> 8) ^ left) & 0x00ff00ff; left ^= temp; right ^= (temp << 8);    temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1);    //the right side needs to be shifted and to get the last four bits of the left side    temp = (left << 8) | ((right >>> 20) & 0x000000f0);    //left needs to be put upside down    left = (right << 24) | ((right << 8) & 0xff0000) | ((right >>> 8) & 0xff00) | ((right >>> 24) & 0xf0);    right = temp;    //now go through and perform these shifts on the left and right keys    for (var i=0; i < shifts.length; i++) {      //shift the keys either one or two bits to the left      if (shifts[i]) {left = (left << 2) | (left >>> 26); right = (right << 2) | (right >>> 26);}      else {left = (left << 1) | (left >>> 27); right = (right << 1) | (right >>> 27);}      left &= -0xf; right &= -0xf;      //now apply PC-2, in such a way that E is easier when encrypting or decrypting      //this conversion will look like PC-2 except only the last 6 bits of each byte are used      //rather than 48 consecutive bits and the order of lines will be according to      //how the S selection functions will be applied: S2, S4, S6, S8, S1, S3, S5, S7      lefttemp = pc2bytes0[left >>> 28] | pc2bytes1[(left >>> 24) & 0xf]        | pc2bytes2[(left >>> 20) & 0xf] | pc2bytes3[(left >>> 16) & 0xf]        | pc2bytes4[(left >>> 12) & 0xf] | pc2bytes5[(left >>> 8) & 0xf]        | pc2bytes6[(left >>> 4) & 0xf];      righttemp = pc2bytes7[right >>> 28] | pc2bytes8[(right >>> 24) & 0xf]        | pc2bytes9[(right >>> 20) & 0xf] | pc2bytes10[(right >>> 16) & 0xf]        | pc2bytes11[(right >>> 12) & 0xf] | pc2bytes12[(right >>> 8) & 0xf]        | pc2bytes13[(right >>> 4) & 0xf];      temp = ((righttemp >>> 16) ^ lefttemp) & 0x0000ffff;      keys[n++] = lefttemp ^ temp; keys[n++] = righttemp ^ (temp << 16);    }  } //for each iterations  //return the keys we've created  return keys;} //end of des_createKeysfunction genkey(key, start, end) {  //8 byte / 64 bit Key (DES) or 192 bit Key  return {key:pad(key.slice(start, end)),vector: 1};}function pad(key) {  for (var i = key.length; i<24; i++) {    key+="0";  }  return key;}var des3iv = '12345678';var DES3 = {  //3DES加密，CBC/PKCS5Padding  encrypt:function(key,input){    var genKey = genkey(key, 0, 24);    return btoa(des(genKey.key, input, 1, 1, des3iv, 1));  },  ////3DES解密，CBC/PKCS5Padding  decrypt:function(key,input){    var genKey = genkey(key, 0, 24);     return des(genKey.key, atob(input), 0, 1, des3iv, 1);   }};

3. Base64.js文件：

/** *create by 2014年7月9日 http://javascript.css-js.com/ *BASE64 Encode and Decode By UTF-8 unicode *可以和java的BASE64编码和解码互相转化 */  var BASE64_MAPPING = [    'A','B','C','D','E','F','G','H',    'I','J','K','L','M','N','O','P',    'Q','R','S','T','U','V','W','X',    'Y','Z','a','b','c','d','e','f',    'g','h','i','j','k','l','m','n',    'o','p','q','r','s','t','u','v',    'w','x','y','z','0','1','2','3',    '4','5','6','7','8','9','+','/'  ];  /**   *ascii convert to binary   */  var _toBinary = function(ascii){    var binary = new Array();    while(ascii > 0){      var b = ascii%2;      ascii = Math.floor(ascii/2);      binary.push(b);    }    /*    var len = binary.length;    if(6-len > 0){      for(var i = 6-len ; i > 0 ; --i){        binary.push(0);      }    }*/    binary.reverse();    return binary;  };  /**   *binary convert to decimal   */  var _toDecimal = function(binary){    var dec = 0;    var p = 0;    for(var i = binary.length-1 ; i >= 0 ; --i){      var b = binary[i];      if(b == 1){        dec += Math.pow(2 , p);      }      ++p;    }    return dec;  };  /**   *unicode convert to utf-8   */  var _toUTF8Binary = function(c , binaryArray){    var mustLen = (8-(c+1)) + ((c-1)*6);    var fatLen = binaryArray.length;    var diff = mustLen - fatLen;    while(--diff >= 0){      binaryArray.unshift(0);    }    var binary = [];    var _c = c;    while(--_c >= 0){      binary.push(1);    }    binary.push(0);    var i = 0 , len = 8 - (c+1);    for(; i < len ; ++i){      binary.push(binaryArray[i]);    }    for(var j = 0 ; j < c-1 ; ++j){      binary.push(1);      binary.push(0);      var sum = 6;      while(--sum >= 0){        binary.push(binaryArray[i++]);      }    }    return binary;  };  var BASE64 = {      /**       *BASE64 Encode       */      encoder:function(str){        var base64_Index = [];        var binaryArray = [];        for(var i = 0 , len = str.length ; i < len ; ++i){          var unicode = str.charCodeAt(i);          var _tmpBinary = _toBinary(unicode);          if(unicode < 0x80){            var _tmpdiff = 8 - _tmpBinary.length;            while(--_tmpdiff >= 0){              _tmpBinary.unshift(0);            }            binaryArray = binaryArray.concat(_tmpBinary);          }else if(unicode >= 0x80 && unicode <= 0x7FF){            binaryArray = binaryArray.concat(_toUTF8Binary(2 , _tmpBinary));          }else if(unicode >= 0x800 && unicode <= 0xFFFF){//UTF-8 3byte            binaryArray = binaryArray.concat(_toUTF8Binary(3 , _tmpBinary));          }else if(unicode >= 0x10000 && unicode <= 0x1FFFFF){//UTF-8 4byte            binaryArray = binaryArray.concat(_toUTF8Binary(4 , _tmpBinary));            }else if(unicode >= 0x200000 && unicode <= 0x3FFFFFF){//UTF-8 5byte            binaryArray = binaryArray.concat(_toUTF8Binary(5 , _tmpBinary));          }else if(unicode >= 4000000 && unicode <= 0x7FFFFFFF){//UTF-8 6byte            binaryArray = binaryArray.concat(_toUTF8Binary(6 , _tmpBinary));          }        }        var extra_Zero_Count = 0;        for(var i = 0 , len = binaryArray.length ; i < len ; i+=6){          var diff = (i+6)-len;          if(diff == 2){            extra_Zero_Count = 2;          }else if(diff == 4){            extra_Zero_Count = 4;          }          //if(extra_Zero_Count > 0){          // len += extra_Zero_Count+1;          //}          var _tmpExtra_Zero_Count = extra_Zero_Count;          while(--_tmpExtra_Zero_Count >= 0){            binaryArray.push(0);          }          base64_Index.push(_toDecimal(binaryArray.slice(i , i+6)));        }        var base64 = '';        for(var i = 0 , len = base64_Index.length ; i < len ; ++i){          base64 += BASE64_MAPPING[base64_Index[i]];        }        for(var i = 0 , len = extra_Zero_Count/2 ; i < len ; ++i){          base64 += '=';        }        return base64;      },      /**       *BASE64 Decode for UTF-8        */      decoder : function(_base64Str){        var _len = _base64Str.length;        var extra_Zero_Count = 0;        /**         *计算在进行BASE64编码的时候，补了几个0         */        if(_base64Str.charAt(_len-1) == '='){          //alert(_base64Str.charAt(_len-1));          //alert(_base64Str.charAt(_len-2));          if(_base64Str.charAt(_len-2) == '='){//两个等号说明补了4个0            extra_Zero_Count = 4;            _base64Str = _base64Str.substring(0 , _len-2);          }else{//一个等号说明补了2个0            extra_Zero_Count = 2;            _base64Str = _base64Str.substring(0 , _len - 1);          }        }        var binaryArray = [];        for(var i = 0 , len = _base64Str.length; i < len ; ++i){          var c = _base64Str.charAt(i);          for(var j = 0 , size = BASE64_MAPPING.length ; j < size ; ++j){            if(c == BASE64_MAPPING[j]){              var _tmp = _toBinary(j);              /*不足6位的补0*/              var _tmpLen = _tmp.length;              if(6-_tmpLen > 0){                for(var k = 6-_tmpLen ; k > 0 ; --k){                  _tmp.unshift(0);                }              }              binaryArray = binaryArray.concat(_tmp);              break;            }          }        }        if(extra_Zero_Count > 0){          binaryArray = binaryArray.slice(0 , binaryArray.length - extra_Zero_Count);        }        var unicode = [];        var unicodeBinary = [];        for(var i = 0 , len = binaryArray.length ; i < len ; ){          if(binaryArray[i] == 0){            unicode=unicode.concat(_toDecimal(binaryArray.slice(i,i+8)));            i += 8;          }else{            var sum = 0;            while(i < len){              if(binaryArray[i] == 1){                ++sum;              }else{                break;              }              ++i;            }            unicodeBinary = unicodeBinary.concat(binaryArray.slice(i+1 , i+8-sum));            i += 8 - sum;            while(sum > 1){              unicodeBinary = unicodeBinary.concat(binaryArray.slice(i+2 , i+8));              i += 8;              --sum;            }            unicode = unicode.concat(_toDecimal(unicodeBinary));            unicodeBinary = [];          }        }        //---------直接转换为结果        var strResult = '';         for(var i = 0 , len = unicode.length ; i < len ;++i){            strResult += String.fromCharCode(unicode[i]);         }        return strResult;      }  };

运行结果：