想必大家对base64并不陌生吧，在本文将为大家介绍下Js中的base64加密解密过程，感兴趣的朋友不要错过
- <script type="text/javascript">
-
- var base64encodechars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
- 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);
-
- function base64encode(str) {
- var out, i, len;
- var c1, c2, c3;
- len = str.length;
- i = 0;
- out = "";
- while (i < len) {
- c1 = str.charCodeAt(i++) & 0xff;
- if (i == len) {
- out += base64encodechars.charAt(c1 >> 2);
- out += base64encodechars.charAt((c1 & 0x3) << 4);
- out += "==";
- break;
- }
- c2 = str.charCodeAt(i++);
- if (i == len) {
- out += base64encodechars.charAt(c1 >> 2);
- out += base64encodechars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xf0) >> 4));
- out += base64encodechars.charAt((c2 & 0xf) << 2);
- out += "=";
- break;
- }
- c3 = str.charCodeAt(i++);
- out += base64encodechars.charAt(c1 >> 2);
- out += base64encodechars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xf0) >> 4));
- out += base64encodechars.charAt(((c2 & 0xf) << 2) | ((c3 & 0xc0) >> 6));
- out += base64encodechars.charAt(c3 & 0x3f);
- }
- return out;
- }
-
- function base64decode(str) {
- var c1, c2, c3, c4;
- var i, len, out;
-
- len = str.length;
-
- i = 0;
- out = "";
- 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;
-
- out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4));
-
- do {
- c3 = str.charCodeAt(i++) & 0xff;
- if (c3 == 61)
- return out;
- c3 = base64decodechars[c3];
- } while (i < len && c3 == -1);
- if (c3 == -1)
- break;
-
- out += String.fromCharCode(((c2 & 0xf) << 4) | ((c3 & 0x3c) >> 2));
-
- do {
- c4 = str.charCodeAt(i++) & 0xff;
- if (c4 == 61)
- return out;
- c4 = base64decodechars[c4];
- } while (i < len && c4 == -1);
- if (c4 == -1)
- break;
- out += String.fromCharCode(((c3 & 0x03) << 6) | c4);
- }
- return out;
- }
- </script>
本文内容由网友自发贡献，版权归原作者所有，本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容，请联系:hwhale#tublm.com(使用前将#替换为@)
