Javascript的base64加密函數(shù)和base64解密函數(shù),仿PHP base64_encode()和base64_decode().附實(shí)例??梢詫s代碼保存到base64.js中,在需要的時(shí)候調(diào)用。 注意:base64加密和解密有固有的算,請不要改動(dòng)以下代碼,否則可能導(dǎo)致程序出錯(cuò),或者無法獲取到正確的結(jié)果。 為了保證代碼的正確性,請下載附件base64.js (沒有實(shí)例),而不要直接復(fù)制本頁代碼。 <script type="text/javascript"> /* * Javascript base64_encode() base64加密函數(shù) 用于生成字符串對應(yīng)的base64加密字符串 * 吳先成 www. ohcc@163.com QQ:229256237 * @param string str 原始字符串 * @return string 加密后的base64字符串 */ function base64_encode(str){ var c1, c2, c3; var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; var i = 0, len= str.length, string = ''; while (i < len){ c1 = str.charCodeAt(i++) & 0xff; if (i == len){ string += base64EncodeChars.charAt(c1 >> 2); string += base64EncodeChars.charAt((c1 & 0x3) << 4); string += "=="; break; } c2 = str.charCodeAt(i++); if (i == len){ string += base64EncodeChars.charAt(c1 >> 2); string += base64EncodeChars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4)); string += base64EncodeChars.charAt((c2 & 0xF) << 2); string += "="; break; } c3 = str.charCodeAt(i++); string += base64EncodeChars.charAt(c1 >> 2); string += base64EncodeChars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4)); string += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >> 6)); string += base64EncodeChars.charAt(c3 & 0x3F) } return string } /* * Javascript base64_decode() base64解密函數(shù) 用于解密base64加密的字符串 * 吳先成 www. ohcc@163.com QQ:229256237 * @param string str base64加密字符串 * @return string 解密后的字符串 */ function base64_decode(str){ var c1, c2, c3, c4; var base64DecodeChars = new Array( -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1 ); var i=0, len = str.length, string = ''; while (i < len){ do{ c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff] } while ( i < len && c1 == -1 ); if (c1 == -1) break; do{ c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff] } while ( i < len && c2 == -1 ); if (c2 == -1) break; string += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4)); do{ c3 = str.charCodeAt(i++) & 0xff; if (c3 == 61) return string; c3 = base64DecodeChars[c3] } while ( i < len && c3 == -1 ); if (c3 == -1) break; string += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2)); do{ c4 = str.charCodeAt(i++) & 0xff; if (c4 == 61) return string; c4 = base64DecodeChars[c4] } while ( i < len && c4 == -1 ); if (c4 == -1) break; string += String.fromCharCode(((c3 & 0x03) << 6) | c4) } return string; } document.write(base64_encode('www.')); document.write('<br />'); document.write(base64_decode('d3d3LjUxLW4uY29t')); </script> |
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