javascript base64編碼和非ASCII符號

Question

我需要在javascript中獲得base64編碼的字符串，（輸入字符串可能包含非ASCII符號）

有一些很好的解決方案嗎？

Answer 1

如果你使用Unicode你最後用Base64編碼字符串中的工作，我會建議使用由WebToolkit.info提出以下腳本。 腳本與UTF-8編碼完全兼容。

/** 
* 
* Base64 encode/decode 
* http://www.webtoolkit.info/ 
* 
**/ 

var Base64 = { 

    // private property 
    _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz/=", 

    // public method for encoding 
    encode : function (input) { 
     var output = ""; 
     var chr1, chr2, chr3, enc1, enc2, enc3, enc4; 
     var i = 0; 

     input = Base64._utf8_encode(input); 

     while (i < input.length) { 

      chr1 = input.charCodeAt(i++); 
      chr2 = input.charCodeAt(i++); 
      chr3 = input.charCodeAt(i++); 

      enc1 = chr1 >> 2; 
      enc2 = ((chr1 & 3) << 4) | (chr2 >> 4); 
      enc3 = ((chr2 & 15) << 2) | (chr3 >> 6); 
      enc4 = chr3 & 63; 

      if (isNaN(chr2)) { 
       enc3 = enc4 = 64; 
      } else if (isNaN(chr3)) { 
       enc4 = 64; 
      } 

      output = output + 
      this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + 
      this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4); 

     } 

     return output; 
    }, 

    // public method for decoding 
    decode : function (input) { 
     var output = ""; 
     var chr1, chr2, chr3; 
     var enc1, enc2, enc3, enc4; 
     var i = 0; 

     input = input.replace(/[^A-Za-z0-9\+\/\=]/g, ""); 

     while (i < input.length) { 

      enc1 = this._keyStr.indexOf(input.charAt(i++)); 
      enc2 = this._keyStr.indexOf(input.charAt(i++)); 
      enc3 = this._keyStr.indexOf(input.charAt(i++)); 
      enc4 = this._keyStr.indexOf(input.charAt(i++)); 

      chr1 = (enc1 << 2) | (enc2 >> 4); 
      chr2 = ((enc2 & 15) << 4) | (enc3 >> 2); 
      chr3 = ((enc3 & 3) << 6) | enc4; 

      output = output + String.fromCharCode(chr1); 

      if (enc3 != 64) { 
       output = output + String.fromCharCode(chr2); 
      } 
      if (enc4 != 64) { 
       output = output + String.fromCharCode(chr3); 
      } 

     } 

     output = Base64._utf8_decode(output); 

     return output; 

    }, 

    // private method for UTF-8 encoding 
    _utf8_encode : function (string) { 
     string = string.replace(/\r\n/g,"\n"); 
     var utftext = ""; 

     for (var n = 0; n < string.length; n++) { 

      var c = string.charCodeAt(n); 

      if (c < 128) { 
       utftext += String.fromCharCode(c); 
      } 
      else if((c > 127) && (c < 2048)) { 
       utftext += String.fromCharCode((c >> 6) | 192); 
       utftext += String.fromCharCode((c & 63) | 128); 
      } 
      else { 
       utftext += String.fromCharCode((c >> 12) | 224); 
       utftext += String.fromCharCode(((c >> 6) & 63) | 128); 
       utftext += String.fromCharCode((c & 63) | 128); 
      } 

     } 

     return utftext; 
    }, 

    // private method for UTF-8 decoding 
    _utf8_decode : function (utftext) { 
     var string = ""; 
     var i = 0; 
     var c = c1 = c2 = 0; 

     while (i < utftext.length) { 

      c = utftext.charCodeAt(i); 

      if (c < 128) { 
       string += String.fromCharCode(c); 
       i++; 
      } 
      else if((c > 191) && (c < 224)) { 
       c2 = utftext.charCodeAt(i+1); 
       string += String.fromCharCode(((c & 31) << 6) | (c2 & 63)); 
       i += 2; 
      } 
      else { 
       c2 = utftext.charCodeAt(i+1); 
       c3 = utftext.charCodeAt(i+2); 
       string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63)); 
       i += 3; 
      } 

     } 

     return string; 
    } 

} 

DEMO：http://www.webtoolkit.info/demo/javascript-base64

Answer 2

沒有語言默認解決方案來獲取字符串爲base64。你必須寫自己的功能，或者偷這一個：

http://ntt.cc/2008/01/19/base64-encoder-decoder-with-javascript.html