js编码解码 punyCode
;(function(w) { var PunycodeModule = function () { function IdnMapping() { this.utf16 = { decode: function (input) { var output = [], i = 0, len = input.length, value, extra; while (i < len) { value = input.charCodeAt(i++); if ((value & 0xF800) === 0xD800) { extra = input.charCodeAt(i++); if (((value & 0xFC00) !== 0xD800) || ((extra & 0xFC00) !== 0xDC00)) { throw new RangeError("UTF-16(decode): Illegal UTF-16 sequence"); } value = ((value & 0x3FF) << 10) + (extra & 0x3FF) + 0x10000; } output.push(value); } return output; }, encode: function (input) { var output = [], i = 0, len = input.length, value; while (i < len) { value = input[i++]; if ((value & 0xF800) === 0xD800) { throw new RangeError("UTF-16(encode): Illegal UTF-16 value"); } if (value > 0xFFFF) { value -= 0x10000; output.push(String.fromCharCode(((value >>> 10) & 0x3FF) | 0xD800)); value = 0xDC00 | (value & 0x3FF); } output.push(String.fromCharCode(value)); } return output.join(""); } } var initial_n = 0x80; var initial_bias = 72; var delimiter = "\x2D"; var base = 36; var damp = 700; var tmin = 1; var tmax = 26; var skew = 38; var maxint = 0x7FFFFFFF; function decode_digit(cp) { return cp - 48 < 10 ? cp - 22 : cp - 65 < 26 ? cp - 65 : cp - 97 < 26 ? cp - 97 : base; } function encode_digit(d, flag) { return d + 22 + 75 * (d < 26) - ((flag != 0) << 5); } function adapt(delta, numpoints, firsttime) { var k; delta = firsttime ? Math.floor(delta / damp) : (delta >> 1); delta += Math.floor(delta / numpoints); for (k = 0; delta > (((base - tmin) * tmax) >> 1) ; k += base) { delta = Math.floor(delta / (base - tmin)); } return Math.floor(k + (base - tmin + 1) * delta / (delta + skew)); } function encode_basic(bcp, flag) { bcp -= (bcp - 97 < 26) << 5; return bcp + ((!flag && (bcp - 65 < 26)) << 5); } this.decode = function (input, preserveCase) { // Dont use utf16 var output = []; var case_flags = []; var input_length = input.length; var n, out, i, bias, basic, j, ic, oldi, w, k, digit, t, len; // Initialize the state: n = initial_n; i = 0; bias = initial_bias; // Handle the basic code points: Let basic be the number of input code // points before the last delimiter, or 0 if there is none, then // copy the first basic code points to the output. basic = input.lastIndexOf(delimiter); if (basic < 0) basic = 0; for (j = 0; j < basic; ++j) { if (preserveCase) case_flags[output.length] = (input.charCodeAt(j) - 65 < 26); if (input.charCodeAt(j) >= 0x80) { throw new RangeError("Illegal input >= 0x80"); } output.push(input.charCodeAt(j)); } // Main decoding loop: Start just after the last delimiter if any // basic code points were copied; start at the beginning otherwise. for (ic = basic > 0 ? basic + 1 : 0; ic < input_length;) { // ic is the index of the next character to be consumed, // Decode a generalized variable-length integer into delta, // which gets added to i. The overflow checking is easier // if we increase i as we go, then subtract off its starting // value at the end to obtain delta. for (oldi = i, w = 1, k = base; ; k += base) { if (ic >= input_length) { throw RangeError("punycode_bad_input(1)"); } digit = decode_digit(input.charCodeAt(ic++)); if (digit >= base) { throw RangeError("punycode_bad_input(2)"); } if (digit > Math.floor((maxint - i) / w)) { throw RangeError("punycode_overflow(1)"); } i += digit * w; t = k <= bias ? tmin : k >= bias + tmax ? tmax : k - bias; if (digit < t) { break; } if (w > Math.floor(maxint / (base - t))) { throw RangeError("punycode_overflow(2)"); } w *= (base - t); } out = output.length + 1; bias = adapt(i - oldi, out, oldi === 0); // i was supposed to wrap around from out to 0, // incrementing n each time, so we'll fix that now: if (Math.floor(i / out) > maxint - n) { throw RangeError("punycode_overflow(3)"); } n += Math.floor(i / out); i %= out; // Insert n at position i of the output: // Case of last character determines uppercase flag: if (preserveCase) { case_flags.splice(i, 0, input.charCodeAt(ic - 1) - 65 < 26); } output.splice(i, 0, n); i++; } if (preserveCase) { for (i = 0, len = output.length; i < len; i++) { if (case_flags[i]) { output[i] = (String.fromCharCode(output[i]).toUpperCase()).charCodeAt(0); } } } return this.utf16.encode(output); }; this.encode = function (input, preserveCase) { //** Bias adaptation function ** var n, delta, h, b, bias, j, m, q, k, t, ijv, case_flags; if (preserveCase) { // Preserve case, step1 of 2: Get a list of the unaltered string case_flags = this.utf16.decode(input); } // Converts the input in UTF-16 to Unicode input = this.utf16.decode(input.toLowerCase()); var input_length = input.length; // Cache the length if (preserveCase) { // Preserve case, step2 of 2: Modify the list to true/false for (j = 0; j < input_length; j++) { case_flags[j] = input[j] != case_flags[j]; } } var output = []; // Initialize the state: n = initial_n; delta = 0; bias = initial_bias; // Handle the basic code points: for (j = 0; j < input_length; ++j) { if (input[j] < 0x80) { output.push( String.fromCharCode( case_flags ? encode_basic(input[j], case_flags[j]) : input[j] ) ); } } h = b = output.length; // h is the number of code points that have been handled, b is the // number of basic code points if (b > 0) output.push(delimiter); // Main encoding loop: // while (h < input_length) { // All non-basic code points < n have been // handled already. Find the next larger one: for (m = maxint, j = 0; j < input_length; ++j) { ijv = input[j]; if (ijv >= n && ijv < m) m = ijv; } // Increase delta enough to advance the decoder's // <n,i> state to <m,0>, but guard against overflow: if (m - n > Math.floor((maxint - delta) / (h + 1))) { throw RangeError("punycode_overflow (1)"); } delta += (m - n) * (h + 1); n = m; for (j = 0; j < input_length; ++j) { ijv = input[j]; if (ijv < n) { if (++delta > maxint) return Error("punycode_overflow(2)"); } if (ijv == n) { // Represent delta as a generalized variable-length integer: for (q = delta, k = base; ; k += base) { t = k <= bias ? tmin : k >= bias + tmax ? tmax : k - bias; if (q < t) break; output.push(String.fromCharCode(encode_digit(t + (q - t) % (base - t), 0))); q = Math.floor((q - t) / (base - t)); } output.push(String.fromCharCode(encode_digit(q, preserveCase && case_flags[j] ? 1 : 0))); bias = adapt(delta, h + 1, h == b); delta = 0; ++h; } } ++delta, ++n; } return output.join(""); } } this.toASCII = function (domain) { var idn = new IdnMapping(); var domainarray = domain.split("."); var out = []; for (var i = 0; i < domainarray.length; ++i) { var s = domainarray[i]; out.push( s.match(/[^A-Za-z0-9-]/) ? "xn--" + idn.encode(s) : s ); } return out.join("."); } this.toUnicode = function (domain) { var idn = new IdnMapping(); var domainarray = domain.split("."); var out = []; for (var i = 0; i < domainarray.length; ++i) { var s = domainarray[i]; out.push( s.match(/^xn--/) ? idn.decode(s.slice(4)) : s ); } return out.join("."); } } w.idnMapping = PunycodeModule; })(window)
<script> window.onload = function () { var idn = new idnMapping(); var str = idn.toASCII("www.北京朝阳.com"); console.log(str); var str1 = idn.toUnicode(str); console.log(str1); } </script>
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