本文共 3026 字，大约阅读时间需要 10 分钟。

1.加密解密方法使用：

//1.加密var str = '124中文内容';var base = new Base64();var result = base.encode(str);//document.write(result);//2.解密var result2 = base.decode(result);document.write(result2);

2.加密、解密算法封装：

/****  Base64 encode / decode**  @author haitao.tu*  @date   2010-04-26*  @email  tuhaitao@foxmail.com**/ function Base64() { 	// private property	_keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="; 	// public method for encoding	this.encode = function (input) {		var output = "";		var chr1, chr2, chr3, enc1, enc2, enc3, enc4;		var i = 0;		input = _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 +			_keyStr.charAt(enc1) + _keyStr.charAt(enc2) +			_keyStr.charAt(enc3) + _keyStr.charAt(enc4);		}		return output;	} 	// public method for decoding	this.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 = _keyStr.indexOf(input.charAt(i++));			enc2 = _keyStr.indexOf(input.charAt(i++));			enc3 = _keyStr.indexOf(input.charAt(i++));			enc4 = _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 = _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;	}}

原文地址：

转载地址：http://qkogi.baihongyu.com/