微信小程序生成二维码（完美解决因链接过长报错问题）
const QR = require('../../utils/weapp-qrcode.js')
var imgData = QR.drawImg(this.data.codeText, {
typeNumber: 4,
errorCorrectLevel: 'M',
size: 500
})
// 返回输出base64编码imgData
weapp-qrcode.js
//--------------------------------------------------------------------- // // QR Code Generator for JavaScript // // Copyright (c) 2009 Kazuhiko Arase // // URL: http://www.d-project.com/ // // Licensed under the MIT license: // http://www.opensource.org/licenses/mit-license.php // // The word 'QR Code' is registered trademark of // DENSO WAVE INCORPORATED // http://www.denso-wave.com/qrcode/faqpatent-e.html // //--------------------------------------------------------------------- //---------------微信小程序基于base64生成二维码插件修改------------------- /* * @Modified: Pudon * @demoURL: https://github.com/Pudon/weapp-qrcode * @Date: 2018-09-11 14:00:05 * @Last Modified by: Pudon * @Last Modified time: 2018-09-12 16:33:19 */ //--------------------------------------------------------------------- /** * qrcode * @param typeNumber 1 to 40 * @param errorCorrectLevel 'L','M','Q','H' */ var qrcode = function(typeNumber, errorCorrectLevel) { var PAD0 = 0xEC; var PAD1 = 0x11; var _typeNumber = typeNumber; var _errorCorrectLevel = QRErrorCorrectLevel[errorCorrectLevel]; var _modules = null; var _moduleCount = 0; var _dataCache = null; var _dataList = new Array(); var _this = {}; var makeImpl = function(test, maskPattern) { _moduleCount = _typeNumber * 4 + 17; _modules = function(moduleCount) { var modules = new Array(moduleCount); for (var row = 0; row < moduleCount; row += 1) { modules[row] = new Array(moduleCount); for (var col = 0; col < moduleCount; col += 1) { modules[row][col] = null; } } return modules; }(_moduleCount); setupPositionProbePattern(0, 0); setupPositionProbePattern(_moduleCount - 7, 0); setupPositionProbePattern(0, _moduleCount - 7); setupPositionAdjustPattern(); setupTimingPattern(); setupTypeInfo(test, maskPattern); if (_typeNumber >= 7) { setupTypeNumber(test); } if (_dataCache == null) { _dataCache = createData(_typeNumber, _errorCorrectLevel, _dataList); } mapData(_dataCache, maskPattern); }; var setupPositionProbePattern = function(row, col) { for (var r = -1; r <= 7; r += 1) { if (row + r <= -1 || _moduleCount <= row + r) continue; for (var c = -1; c <= 7; c += 1) { if (col + c <= -1 || _moduleCount <= col + c) continue; if ( (0 <= r && r <= 6 && (c == 0 || c == 6) ) || (0 <= c && c <= 6 && (r == 0 || r == 6) ) || (2 <= r && r <= 4 && 2 <= c && c <= 4) ) { _modules[row + r][col + c] = true; } else { _modules[row + r][col + c] = false; } } } }; var getBestMaskPattern = function() { var minLostPoint = 0; var pattern = 0; for (var i = 0; i < 8; i += 1) { makeImpl(true, i); var lostPoint = QRUtil.getLostPoint(_this); if (i == 0 || minLostPoint > lostPoint) { minLostPoint = lostPoint; pattern = i; } } return pattern; }; var setupTimingPattern = function() { for (var r = 8; r < _moduleCount - 8; r += 1) { if (_modules[r][6] != null) { continue; } _modules[r][6] = (r % 2 == 0); } for (var c = 8; c < _moduleCount - 8; c += 1) { if (_modules[6][c] != null) { continue; } _modules[6][c] = (c % 2 == 0); } }; var setupPositionAdjustPattern = function() { var pos = QRUtil.getPatternPosition(_typeNumber); for (var i = 0; i < pos.length; i += 1) { for (var j = 0; j < pos.length; j += 1) { var row = pos[i]; var col = pos[j]; if (_modules[row][col] != null) { continue; } for (var r = -2; r <= 2; r += 1) { for (var c = -2; c <= 2; c += 1) { if (r == -2 || r == 2 || c == -2 || c == 2 || (r == 0 && c == 0) ) { _modules[row + r][col + c] = true; } else { _modules[row + r][col + c] = false; } } } } } }; var setupTypeNumber = function(test) { var bits = QRUtil.getBCHTypeNumber(_typeNumber); for (var i = 0; i < 18; i += 1) { var mod = (!test && ( (bits >> i) & 1) == 1); _modules[Math.floor(i / 3)][i % 3 + _moduleCount - 8 - 3] = mod; } for (var i = 0; i < 18; i += 1) { var mod = (!test && ( (bits >> i) & 1) == 1); _modules[i % 3 + _moduleCount - 8 - 3][Math.floor(i / 3)] = mod; } }; var setupTypeInfo = function(test, maskPattern) { var data = (_errorCorrectLevel << 3) | maskPattern; var bits = QRUtil.getBCHTypeInfo(data); // vertical for (var i = 0; i < 15; i += 1) { var mod = (!test && ( (bits >> i) & 1) == 1); if (i < 6) { _modules[i][8] = mod; } else if (i < 8) { _modules[i + 1][8] = mod; } else { _modules[_moduleCount - 15 + i][8] = mod; } } // horizontal for (var i = 0; i < 15; i += 1) { var mod = (!test && ( (bits >> i) & 1) == 1); if (i < 8) { _modules[8][_moduleCount - i - 1] = mod; } else if (i < 9) { _modules[8][15 - i - 1 + 1] = mod; } else { _modules[8][15 - i - 1] = mod; } } // fixed module _modules[_moduleCount - 8][8] = (!test); }; var mapData = function(data, maskPattern) { var inc = -1; var row = _moduleCount - 1; var bitIndex = 7; var byteIndex = 0; var maskFunc = QRUtil.getMaskFunction(maskPattern); for (var col = _moduleCount - 1; col > 0; col -= 2) { if (col == 6) col -= 1; while (true) { for (var c = 0; c < 2; c += 1) { if (_modules[row][col - c] == null) { var dark = false; if (byteIndex < data.length) { dark = ( ( (data[byteIndex] >>> bitIndex) & 1) == 1); } var mask = maskFunc(row, col - c); if (mask) { dark = !dark; } _modules[row][col - c] = dark; bitIndex -= 1; if (bitIndex == -1) { byteIndex += 1; bitIndex = 7; } } } row += inc; if (row < 0 || _moduleCount <= row) { row -= inc; inc = -inc; break; } } } }; var createBytes = function(buffer, rsBlocks) { var offset = 0; var maxDcCount = 0; var maxEcCount = 0; var dcdata = new Array(rsBlocks.length); var ecdata = new Array(rsBlocks.length); for (var r = 0; r < rsBlocks.length; r += 1) { var dcCount = rsBlocks[r].dataCount; var ecCount = rsBlocks[r].totalCount - dcCount; maxDcCount = Math.max(maxDcCount, dcCount); maxEcCount = Math.max(maxEcCount, ecCount); dcdata[r] = new Array(dcCount); for (var i = 0; i < dcdata[r].length; i += 1) { dcdata[r][i] = 0xff & buffer.getBuffer()[i + offset]; } offset += dcCount; var rsPoly = QRUtil.getErrorCorrectPolynomial(ecCount); var rawPoly = qrPolynomial(dcdata[r], rsPoly.getLength() - 1); var modPoly = rawPoly.mod(rsPoly); ecdata[r] = new Array(rsPoly.getLength() - 1); for (var i = 0; i < ecdata[r].length; i += 1) { var modIndex = i + modPoly.getLength() - ecdata[r].length; ecdata[r][i] = (modIndex >= 0)? modPoly.getAt(modIndex) : 0; } } var totalCodeCount = 0; for (var i = 0; i < rsBlocks.length; i += 1) { totalCodeCount += rsBlocks[i].totalCount; } var data = new Array(totalCodeCount); var index = 0; for (var i = 0; i < maxDcCount; i += 1) { for (var r = 0; r < rsBlocks.length; r += 1) { if (i < dcdata[r].length) { data[index] = dcdata[r][i]; index += 1; } } } for (var i = 0; i < maxEcCount; i += 1) { for (var r = 0; r < rsBlocks.length; r += 1) { if (i < ecdata[r].length) { data[index] = ecdata[r][i]; index += 1; } } } return data; }; var createData = function(typeNumber, errorCorrectLevel, dataList) { var rsBlocks = QRRSBlock.getRSBlocks(typeNumber, errorCorrectLevel); var buffer = qrBitBuffer(); for (var i = 0; i < dataList.length; i += 1) { var data = dataList[i]; buffer.put(data.getMode(), 4); buffer.put(data.getLength(), QRUtil.getLengthInBits(data.getMode(), typeNumber) ); data.write(buffer); } // calc num max data. var totalDataCount = 0; for (var i = 0; i < rsBlocks.length; i += 1) { totalDataCount += rsBlocks[i].dataCount; } if (buffer.getLengthInBits() > totalDataCount * 8) { throw new Error('code length overflow. (' + buffer.getLengthInBits() + '>' + totalDataCount * 8 + ')'); } // end code if (buffer.getLengthInBits() + 4 <= totalDataCount * 8) { buffer.put(0, 4); } // padding while (buffer.getLengthInBits() % 8 != 0) { buffer.putBit(false); } // padding while (true) { if (buffer.getLengthInBits() >= totalDataCount * 8) { break; } buffer.put(PAD0, 8); if (buffer.getLengthInBits() >= totalDataCount * 8) { break; } buffer.put(PAD1, 8); } return createBytes(buffer, rsBlocks); }; _this.addData = function(data) { var newData = qr8BitByte(data); _dataList.push(newData); _dataCache = null; }; _this.isDark = function(row, col) { if (row < 0 || _moduleCount <= row || col < 0 || _moduleCount <= col) { throw new Error(row + ',' + col); } return _modules[row][col]; }; _this.getModuleCount = function() { return _moduleCount; }; _this.make = function() { makeImpl(false, getBestMaskPattern() ); }; _this.createTableTag = function(cellSize, margin) { cellSize = cellSize || 2; margin = (typeof margin == 'undefined')? cellSize * 4 : margin; var qrHtml = ''; qrHtml += '<table style="'; qrHtml += ' border-width: 0px; border-style: none;'; qrHtml += ' border-collapse: collapse;'; qrHtml += ' padding: 0px; margin: ' + margin + 'px;'; qrHtml += '">'; qrHtml += '<tbody>'; for (var r = 0; r < _this.getModuleCount(); r += 1) { qrHtml += '<tr>'; for (var c = 0; c < _this.getModuleCount(); c += 1) { qrHtml += '<td style="'; qrHtml += ' border-width: 0px; border-style: none;'; qrHtml += ' border-collapse: collapse;'; qrHtml += ' padding: 0px; margin: 0px;'; qrHtml += ' width: ' + cellSize + 'px;'; qrHtml += ' height: ' + cellSize + 'px;'; qrHtml += ' background-color: '; qrHtml += _this.isDark(r, c)? '#000000' : '#ffffff'; qrHtml += ';'; qrHtml += '"/>'; } qrHtml += '</tr>'; } qrHtml += '</tbody>'; qrHtml += '</table>'; return qrHtml; }; _this.createImgTag = function(cellSize, margin, size) { cellSize = cellSize || 2; margin = (typeof margin == 'undefined')? cellSize * 4 : margin; var min = margin; var max = _this.getModuleCount() * cellSize + margin; return createImgTag(size, size, function(x, y) { if (min <= x && x < max && min <= y && y < max) { var c = Math.floor( (x - min) / cellSize); var r = Math.floor( (y - min) / cellSize); return _this.isDark(r, c)? 0 : 1; } else { return 1; } } ); }; return _this; }; //--------------------------------------------------------------------- // qrcode.stringToBytes //--------------------------------------------------------------------- qrcode.stringToBytes = function(s) { var bytes = new Array(); for (var i = 0; i < s.length; i += 1) { var c = s.charCodeAt(i); bytes.push(c & 0xff); } return bytes; }; //--------------------------------------------------------------------- // qrcode.createStringToBytes //--------------------------------------------------------------------- /** * @param unicodeData base64 string of byte array. * [16bit Unicode],[16bit Bytes], ... * @param numChars */ qrcode.createStringToBytes = function(unicodeData, numChars) { // create conversion map. var unicodeMap = function() { var bin = base64DecodeInputStream(unicodeData); var read = function() { var b = bin.read(); if (b == -1) throw new Error(); return b; }; var count = 0; var unicodeMap = {}; while (true) { var b0 = bin.read(); if (b0 == -1) break; var b1 = read(); var b2 = read(); var b3 = read(); var k = String.fromCharCode( (b0 << 8) | b1); var v = (b2 << 8) | b3; unicodeMap[k] = v; count += 1; } if (count != numChars) { throw new Error(count + ' != ' + numChars); } return unicodeMap; }(); var unknownChar = '?'.charCodeAt(0); return function(s) { var bytes = new Array(); for (var i = 0; i < s.length; i += 1) { var c = s.charCodeAt(i); if (c < 128) { bytes.push(c); } else { var b = unicodeMap[s.charAt(i)]; if (typeof b == 'number') { if ( (b & 0xff) == b) { // 1byte bytes.push(b); } else { // 2bytes bytes.push(b >>> 8); bytes.push(b & 0xff); } } else { bytes.push(unknownChar); } } } return bytes; }; }; //--------------------------------------------------------------------- // QRMode //--------------------------------------------------------------------- var QRMode = { MODE_NUMBER : 1 << 0, MODE_ALPHA_NUM : 1 << 1, MODE_8BIT_BYTE : 1 << 2, MODE_KANJI : 1 << 3 }; //--------------------------------------------------------------------- // QRErrorCorrectLevel //--------------------------------------------------------------------- var QRErrorCorrectLevel = { L : 1, M : 0, Q : 3, H : 2 }; //--------------------------------------------------------------------- // QRMaskPattern //--------------------------------------------------------------------- var QRMaskPattern = { PATTERN000 : 0, PATTERN001 : 1, PATTERN010 : 2, PATTERN011 : 3, PATTERN100 : 4, PATTERN101 : 5, PATTERN110 : 6, PATTERN111 : 7 }; //--------------------------------------------------------------------- // QRUtil //--------------------------------------------------------------------- var QRUtil = function() { var PATTERN_POSITION_TABLE = [ [], [6, 18], [6, 22], [6, 26], [6, 30], [6, 34], [6, 22, 38], [6, 24, 42], [6, 26, 46], [6, 28, 50], [6, 30, 54], [6, 32, 58], [6, 34, 62], [6, 26, 46, 66], [6, 26, 48, 70], [6, 26, 50, 74], [6, 30, 54, 78], [6, 30, 56, 82], [6, 30, 58, 86], [6, 34, 62, 90], [6, 28, 50, 72, 94], [6, 26, 50, 74, 98], [6, 30, 54, 78, 102], [6, 28, 54, 80, 106], [6, 32, 58, 84, 110], [6, 30, 58, 86, 114], [6, 34, 62, 90, 118], [6, 26, 50, 74, 98, 122], [6, 30, 54, 78, 102, 126], [6, 26, 52, 78, 104, 130], [6, 30, 56, 82, 108, 134], [6, 34, 60, 86, 112, 138], [6, 30, 58, 86, 114, 142], [6, 34, 62, 90, 118, 146], [6, 30, 54, 78, 102, 126, 150], [6, 24, 50, 76, 102, 128, 154], [6, 28, 54, 80, 106, 132, 158], [6, 32, 58, 84, 110, 136, 162], [6, 26, 54, 82, 110, 138, 166], [6, 30, 58, 86, 114, 142, 170] ]; var G15 = (1 << 10) | (1 << 8) | (1 << 5) | (1 << 4) | (1 << 2) | (1 << 1) | (1 << 0); var G18 = (1 << 12) | (1 << 11) | (1 << 10) | (1 << 9) | (1 << 8) | (1 << 5) | (1 << 2) | (1 << 0); var G15_MASK = (1 << 14) | (1 << 12) | (1 << 10) | (1 << 4) | (1 << 1); var _this = {}; var getBCHDigit = function(data) { var digit = 0; while (data != 0) { digit += 1; data >>>= 1; } return digit; }; _this.getBCHTypeInfo = function(data) { var d = data << 10; while (getBCHDigit(d) - getBCHDigit(G15) >= 0) { d ^= (G15 << (getBCHDigit(d) - getBCHDigit(G15) ) ); } return ( (data << 10) | d) ^ G15_MASK; }; _this.getBCHTypeNumber = function(data) { var d = data << 12; while (getBCHDigit(d) - getBCHDigit(G18) >= 0) { d ^= (G18 << (getBCHDigit(d) - getBCHDigit(G18) ) ); } return (data << 12) | d; }; _this.getPatternPosition = function(typeNumber) { return PATTERN_POSITION_TABLE[typeNumber - 1]; }; _this.getMaskFunction = function(maskPattern) { switch (maskPattern) { case QRMaskPattern.PATTERN000 : return function(i, j) { return (i + j) % 2 == 0; }; case QRMaskPattern.PATTERN001 : return function(i, j) { return i % 2 == 0; }; case QRMaskPattern.PATTERN010 : return function(i, j) { return j % 3 == 0; }; case QRMaskPattern.PATTERN011 : return function(i, j) { return (i + j) % 3 == 0; }; case QRMaskPattern.PATTERN100 : return function(i, j) { return (Math.floor(i / 2) + Math.floor(j / 3) ) % 2 == 0; }; case QRMaskPattern.PATTERN101 : return function(i, j) { return (i * j) % 2 + (i * j) % 3 == 0; }; case QRMaskPattern.PATTERN110 : return function(i, j) { return ( (i * j) % 2 + (i * j) % 3) % 2 == 0; }; case QRMaskPattern.PATTERN111 : return function(i, j) { return ( (i * j) % 3 + (i + j) % 2) % 2 == 0; }; default : throw new Error('bad maskPattern:' + maskPattern); } }; _this.getErrorCorrectPolynomial = function(errorCorrectLength) { var a = qrPolynomial([1], 0); for (var i = 0; i < errorCorrectLength; i += 1) { a = a.multiply(qrPolynomial([1, QRMath.gexp(i)], 0) ); } return a; }; _this.getLengthInBits = function(mode, type) { if (1 <= type && type < 10) { // 1 - 9 switch(mode) { case QRMode.MODE_NUMBER : return 10; case QRMode.MODE_ALPHA_NUM : return 9; case QRMode.MODE_8BIT_BYTE : return 8; case QRMode.MODE_KANJI : return 8; default : throw new Error('mode:' + mode); } } else if (type < 27) { // 10 - 26 switch(mode) { case QRMode.MODE_NUMBER : return 12; case QRMode.MODE_ALPHA_NUM : return 11; case QRMode.MODE_8BIT_BYTE : return 16; case QRMode.MODE_KANJI : return 10; default : throw new Error('mode:' + mode); } } else if (type < 41) { // 27 - 40 switch(mode) { case QRMode.MODE_NUMBER : return 14; case QRMode.MODE_ALPHA_NUM : return 13; case QRMode.MODE_8BIT_BYTE : return 16; case QRMode.MODE_KANJI : return 12; default : throw new Error('mode:' + mode); } } else { throw new Error('type:' + type); } }; _this.getLostPoint = function(qrcode) { var moduleCount = qrcode.getModuleCount(); var lostPoint = 0; // LEVEL1 for (var row = 0; row < moduleCount; row += 1) { for (var col = 0; col < moduleCount; col += 1) { var sameCount = 0; var dark = qrcode.isDark(row, col); for (var r = -1; r <= 1; r += 1) { if (row + r < 0 || moduleCount <= row + r) { continue; } for (var c = -1; c <= 1; c += 1) { if (col + c < 0 || moduleCount <= col + c) { continue; } if (r == 0 && c == 0) { continue; } if (dark == qrcode.isDark(row + r, col + c) ) { sameCount += 1; } } } if (sameCount > 5) { lostPoint += (3 + sameCount - 5); } } }; // LEVEL2 for (var row = 0; row < moduleCount - 1; row += 1) { for (var col = 0; col < moduleCount - 1; col += 1) { var count = 0; if (qrcode.isDark(row, col) ) count += 1; if (qrcode.isDark(row + 1, col) ) count += 1; if (qrcode.isDark(row, col + 1) ) count += 1; if (qrcode.isDark(row + 1, col + 1) ) count += 1; if (count == 0 || count == 4) { lostPoint += 3; } } } // LEVEL3 for (var row = 0; row < moduleCount; row += 1) { for (var col = 0; col < moduleCount - 6; col += 1) { if (qrcode.isDark(row, col) && !qrcode.isDark(row, col + 1) && qrcode.isDark(row, col + 2) && qrcode.isDark(row, col + 3) && qrcode.isDark(row, col + 4) && !qrcode.isDark(row, col + 5) && qrcode.isDark(row, col + 6) ) { lostPoint += 40; } } } for (var col = 0; col < moduleCount; col += 1) { for (var row = 0; row < moduleCount - 6; row += 1) { if (qrcode.isDark(row, col) && !qrcode.isDark(row + 1, col) && qrcode.isDark(row + 2, col) && qrcode.isDark(row + 3, col) && qrcode.isDark(row + 4, col) && !qrcode.isDark(row + 5, col) && qrcode.isDark(row + 6, col) ) { lostPoint += 40; } } } // LEVEL4 var darkCount = 0; for (var col = 0; col < moduleCount; col += 1) { for (var row = 0; row < moduleCount; row += 1) { if (qrcode.isDark(row, col) ) { darkCount += 1; } } } var ratio = Math.abs(100 * darkCount / moduleCount / moduleCount - 50) / 5; lostPoint += ratio * 10; return lostPoint; }; return _this; }(); //--------------------------------------------------------------------- // QRMath //--------------------------------------------------------------------- var QRMath = function() { var EXP_TABLE = new Array(256); var LOG_TABLE = new Array(256); // initialize tables for (var i = 0; i < 8; i += 1) { EXP_TABLE[i] = 1 << i; } for (var i = 8; i < 256; i += 1) { EXP_TABLE[i] = EXP_TABLE[i - 4] ^ EXP_TABLE[i - 5] ^ EXP_TABLE[i - 6] ^ EXP_TABLE[i - 8]; } for (var i = 0; i < 255; i += 1) { LOG_TABLE[EXP_TABLE[i] ] = i; } var _this = {}; _this.glog = function(n) { if (n < 1) { throw new Error('glog(' + n + ')'); } return LOG_TABLE[n]; }; _this.gexp = function(n) { while (n < 0) { n += 255; } while (n >= 256) { n -= 255; } return EXP_TABLE[n]; }; return _this; }(); //--------------------------------------------------------------------- // qrPolynomial //--------------------------------------------------------------------- function qrPolynomial(num, shift) { if (typeof num.length == 'undefined') { throw new Error(num.length + '/' + shift); } var _num = function() { var offset = 0; while (offset < num.length && num[offset] == 0) { offset += 1; } var _num = new Array(num.length - offset + shift); for (var i = 0; i < num.length - offset; i += 1) { _num[i] = num[i + offset]; } return _num; }(); var _this = {}; _this.getAt = function(index) { return _num[index]; }; _this.getLength = function() { return _num.length; }; _this.multiply = function(e) { var num = new Array(_this.getLength() + e.getLength() - 1); for (var i = 0; i < _this.getLength(); i += 1) { for (var j = 0; j < e.getLength(); j += 1) { num[i + j] ^= QRMath.gexp(QRMath.glog(_this.getAt(i) ) + QRMath.glog(e.getAt(j) ) ); } } return qrPolynomial(num, 0); }; _this.mod = function(e) { if (_this.getLength() - e.getLength() < 0) { return _this; } var ratio = QRMath.glog(_this.getAt(0) ) - QRMath.glog(e.getAt(0) ); var num = new Array(_this.getLength() ); for (var i = 0; i < _this.getLength(); i += 1) { num[i] = _this.getAt(i); } for (var i = 0; i < e.getLength(); i += 1) { num[i] ^= QRMath.gexp(QRMath.glog(e.getAt(i) ) + ratio); } // recursive call return qrPolynomial(num, 0).mod(e); }; return _this; }; //--------------------------------------------------------------------- // QRRSBlock //--------------------------------------------------------------------- var QRRSBlock = function() { // [1: [L, M, Q, H], ..] var RS_BLOCK_TABLE=[[1,26,19],[1,26,16],[1,26,13],[1,26,9],[1,44,34],[1,44,28],[1,44,22],[1,44,16],[1,70,55],[1,70,44],[2,35,17],[2,35,13],[1,100,80],[2,50,32],[2,50,24],[4,25,9],[1,134,108],[2,67,43],[2,33,15,2,34,16],[2,33,11,2,34,12],[2,86,68],[4,43,27],[4,43,19],[4,43,15],[2,98,78],[4,49,31],[2,32,14,4,33,15],[4,39,13,1,40,14],[2,121,97],[2,60,38,2,61,39],[4,40,18,2,41,19],[4,40,14,2,41,15],[2,146,116],[3,58,36,2,59,37],[4,36,16,4,37,17],[4,36,12,4,37,13],[2,86,68,2,87,69],[4,69,43,1,70,44],[6,43,19,2,44,20],[6,43,15,2,44,16],[4,101,81],[1,80,50,4,81,51],[4,50,22,4,51,23],[3,36,12,8,37,13],[2,116,92,2,117,93],[6,58,36,2,59,37],[4,46,20,6,47,21],[7,42,14,4,43,15],[4,133,107],[8,59,37,1,60,38],[8,44,20,4,45,21],[12,33,11,4,34,12],[3,145,115,1,146,116],[4,64,40,5,65,41],[11,36,16,5,37,17],[11,36,12,5,37,13],[5,109,87,1,110,88],[5,65,41,5,66,42],[5,54,24,7,55,25],[11,36,12],[5,122,98,1,123,99],[7,73,45,3,74,46],[15,43,19,2,44,20],[3,45,15,13,46,16],[1,135,107,5,136,108],[10,74,46,1,75,47],[1,50,22,15,51,23],[2,42,14,17,43,15],[5,150,120,1,151,121],[9,69,43,4,70,44],[17,50,22,1,51,23],[2,42,14,19,43,15],[3,141,113,4,142,114],[3,70,44,11,71,45],[17,47,21,4,48,22],[9,39,13,16,40,14],[3,135,107,5,136,108],[3,67,41,13,68,42],[15,54,24,5,55,25],[15,43,15,10,44,16],[4,144,116,4,145,117],[17,68,42],[17,50,22,6,51,23],[19,46,16,6,47,17],[2,139,111,7,140,112],[17,74,46],[7,54,24,16,55,25],[34,37,13],[4,151,121,5,152,122],[4,75,47,14,76,48],[11,54,24,14,55,25],[16,45,15,14,46,16],[6,147,117,4,148,118],[6,73,45,14,74,46],[11,54,24,16,55,25],[30,46,16,2,47,17],[8,132,106,4,133,107],[8,75,47,13,76,48],[7,54,24,22,55,25],[22,45,15,13,46,16],[10,142,114,2,143,115],[19,74,46,4,75,47],[28,50,22,6,51,23],[33,46,16,4,47,17],[8,152,122,4,153,123],[22,73,45,3,74,46],[8,53,23,26,54,24],[12,45,15,28,46,16],[3,147,117,10,148,118],[3,73,45,23,74,46],[4,54,24,31,55,25],[11,45,15,31,46,16],[7,146,116,7,147,117],[21,73,45,7,74,46],[1,53,23,37,54,24],[19,45,15,26,46,16],[5,145,115,10,146,116],[19,75,47,10,76,48],[15,54,24,25,55,25],[23,45,15,25,46,16],[13,145,115,3,146,116],[2,74,46,29,75,47],[42,54,24,1,55,25],[23,45,15,28,46,16],[17,145,115],[10,74,46,23,75,47],[10,54,24,35,55,25],[19,45,15,35,46,16],[17,145,115,1,146,116],[14,74,46,21,75,47],[29,54,24,19,55,25],[11,45,15,46,46,16],[13,145,115,6,146,116],[14,74,46,23,75,47],[44,54,24,7,55,25],[59,46,16,1,47,17],[12,151,121,7,152,122],[12,75,47,26,76,48],[39,54,24,14,55,25],[22,45,15,41,46,16],[6,151,121,14,152,122],[6,75,47,34,76,48],[46,54,24,10,55,25],[2,45,15,64,46,16],[17,152,122,4,153,123],[29,74,46,14,75,47],[49,54,24,10,55,25],[24,45,15,46,46,16],[4,152,122,18,153,123],[13,74,46,32,75,47],[48,54,24,14,55,25],[42,45,15,32,46,16],[20,147,117,4,148,118],[40,75,47,7,76,48],[43,54,24,22,55,25],[10,45,15,67,46,16],[19,148,118,6,149,119],[18,75,47,31,76,48],[34,54,24,34,55,25],[20,45,15,61,46,16]]; var qrRSBlock = function(totalCount, dataCount) { var _this = {}; _this.totalCount = totalCount; _this.dataCount = dataCount; return _this; }; var _this = {}; var getRsBlockTable = function(typeNumber, errorCorrectLevel) { switch(errorCorrectLevel) { case QRErrorCorrectLevel.L : return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 0]; case QRErrorCorrectLevel.M : return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 1]; case QRErrorCorrectLevel.Q : return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 2]; case QRErrorCorrectLevel.H : return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 3]; default : return undefined; } }; _this.getRSBlocks = function(typeNumber, errorCorrectLevel) { var rsBlock = getRsBlockTable(typeNumber, errorCorrectLevel); if (typeof rsBlock == 'undefined') { throw new Error('bad rs block @ typeNumber:' + typeNumber + '/errorCorrectLevel:' + errorCorrectLevel); } var length = rsBlock.length / 3; var list = new Array(); for (var i = 0; i < length; i += 1) { var count = rsBlock[i * 3 + 0]; var totalCount = rsBlock[i * 3 + 1]; var dataCount = rsBlock[i * 3 + 2]; for (var j = 0; j < count; j += 1) { list.push(qrRSBlock(totalCount, dataCount) ); } } return list; }; return _this; }(); //--------------------------------------------------------------------- // qrBitBuffer //--------------------------------------------------------------------- var qrBitBuffer = function() { var _buffer = new Array(); var _length = 0; var _this = {}; _this.getBuffer = function() { return _buffer; }; _this.getAt = function(index) { var bufIndex = Math.floor(index / 8); return ( (_buffer[bufIndex] >>> (7 - index % 8) ) & 1) == 1; }; _this.put = function(num, length) { for (var i = 0; i < length; i += 1) { _this.putBit( ( (num >>> (length - i - 1) ) & 1) == 1); } }; _this.getLengthInBits = function() { return _length; }; _this.putBit = function(bit) { var bufIndex = Math.floor(_length / 8); if (_buffer.length <= bufIndex) { _buffer.push(0); } if (bit) { _buffer[bufIndex] |= (0x80 >>> (_length % 8) ); } _length += 1; }; return _this; }; //--------------------------------------------------------------------- // qr8BitByte //--------------------------------------------------------------------- var qr8BitByte = function(data) { var _mode = QRMode.MODE_8BIT_BYTE; var _data = data; var _parsedData = []; var _this = {}; // Added to support UTF-8 Characters for (var i = 0, l = _data.length; i < l; i++) { var byteArray = []; var code = _data.charCodeAt(i); if (code > 0x10000) { byteArray[0] = 0xF0 | ((code & 0x1C0000) >>> 18); byteArray[1] = 0x80 | ((code & 0x3F000) >>> 12); byteArray[2] = 0x80 | ((code & 0xFC0) >>> 6); byteArray[3] = 0x80 | (code & 0x3F); } else if (code > 0x800) { byteArray[0] = 0xE0 | ((code & 0xF000) >>> 12); byteArray[1] = 0x80 | ((code & 0xFC0) >>> 6); byteArray[2] = 0x80 | (code & 0x3F); } else if (code > 0x80) { byteArray[0] = 0xC0 | ((code & 0x7C0) >>> 6); byteArray[1] = 0x80 | (code & 0x3F); } else { byteArray[0] = code; } // Fix Unicode corruption bug _parsedData.push(byteArray); } _parsedData = Array.prototype.concat.apply([], _parsedData); if (_parsedData.length != _data.length) { _parsedData.unshift(191); _parsedData.unshift(187); _parsedData.unshift(239); } var _bytes = _parsedData; _this.getMode = function() { return _mode; }; _this.getLength = function(buffer) { return _bytes.length; }; _this.write = function(buffer) { for (var i = 0; i < _bytes.length; i += 1) { buffer.put(_bytes[i], 8); } }; return _this; }; //===================================================================== // GIF Support etc. // //--------------------------------------------------------------------- // byteArrayOutputStream //--------------------------------------------------------------------- var byteArrayOutputStream = function() { var _bytes = new Array(); var _this = {}; _this.writeByte = function(b) { _bytes.push(b & 0xff); }; _this.writeShort = function(i) { _this.writeByte(i); _this.writeByte(i >>> 8); }; _this.writeBytes = function(b, off, len) { off = off || 0; len = len || b.length; for (var i = 0; i < len; i += 1) { _this.writeByte(b[i + off]); } }; _this.writeString = function(s) { for (var i = 0; i < s.length; i += 1) { _this.writeByte(s.charCodeAt(i) ); } }; _this.toByteArray = function() { return _bytes; }; _this.toString = function() { var s = ''; s += '['; for (var i = 0; i < _bytes.length; i += 1) { if (i > 0) { s += ','; } s += _bytes[i]; } s += ']'; return s; }; return _this; }; //--------------------------------------------------------------------- // base64EncodeOutputStream //--------------------------------------------------------------------- var base64EncodeOutputStream = function() { var _buffer = 0; var _buflen = 0; var _length = 0; var _base64 = ''; var _this = {}; var writeEncoded = function(b) { _base64 += String.fromCharCode(encode(b & 0x3f) ); }; var encode = function(n) { if (n < 0) { // error. } else if (n < 26) { return 0x41 + n; } else if (n < 52) { return 0x61 + (n - 26); } else if (n < 62) { return 0x30 + (n - 52); } else if (n == 62) { return 0x2b; } else if (n == 63) { return 0x2f; } throw new Error('n:' + n); }; _this.writeByte = function(n) { _buffer = (_buffer << 8) | (n & 0xff); _buflen += 8; _length += 1; while (_buflen >= 6) { writeEncoded(_buffer >>> (_buflen - 6) ); _buflen -= 6; } }; _this.flush = function() { if (_buflen > 0) { writeEncoded(_buffer << (6 - _buflen) ); _buffer = 0; _buflen = 0; } if (_length % 3 != 0) { // padding var padlen = 3 - _length % 3; for (var i = 0; i < padlen; i += 1) { _base64 += '='; } } }; _this.toString = function() { return _base64; }; return _this; }; //--------------------------------------------------------------------- // base64DecodeInputStream //--------------------------------------------------------------------- var base64DecodeInputStream = function(str) { var _str = str; var _pos = 0; var _buffer = 0; var _buflen = 0; var _this = {}; _this.read = function() { while (_buflen < 8) { if (_pos >= _str.length) { if (_buflen == 0) { return -1; } throw new Error('unexpected end of file./' + _buflen); } var c = _str.charAt(_pos); _pos += 1; if (c == '=') { _buflen = 0; return -1; } else if (c.match(/^\s$/) ) { // ignore if whitespace. continue; } _buffer = (_buffer << 6) | decode(c.charCodeAt(0) ); _buflen += 6; } var n = (_buffer >>> (_buflen - 8) ) & 0xff; _buflen -= 8; return n; }; var decode = function(c) { if (0x41 <= c && c <= 0x5a) { return c - 0x41; } else if (0x61 <= c && c <= 0x7a) { return c - 0x61 + 26; } else if (0x30 <= c && c <= 0x39) { return c - 0x30 + 52; } else if (c == 0x2b) { return 62; } else if (c == 0x2f) { return 63; } else { throw new Error('c:' + c); } }; return _this; }; //--------------------------------------------------------------------- // gifImage (B/W) //--------------------------------------------------------------------- var gifImage = function(width, height) { var _width = width; var _height = height; var _data = new Array(width * height); var _this = {}; _this.setPixel = function(x, y, pixel) { _data[y * _width + x] = pixel; }; _this.write = function(out) { //--------------------------------- // GIF Signature out.writeString('GIF87a'); //--------------------------------- // Screen Descriptor out.writeShort(_width); out.writeShort(_height); out.writeByte(0x80); // 2bit out.writeByte(0); out.writeByte(0); //--------------------------------- // Global Color Map // black out.writeByte(0x00); out.writeByte(0x00); out.writeByte(0x00); // white out.writeByte(0xff); out.writeByte(0xff); out.writeByte(0xff); //--------------------------------- // Image Descriptor out.writeString(','); out.writeShort(0); out.writeShort(0); out.writeShort(_width); out.writeShort(_height); out.writeByte(0); //--------------------------------- // Local Color Map //--------------------------------- // Raster Data var lzwMinCodeSize = 2; var raster = getLZWRaster(lzwMinCodeSize); out.writeByte(lzwMinCodeSize); var offset = 0; while (raster.length - offset > 255) { out.writeByte(255); out.writeBytes(raster, offset, 255); offset += 255; } out.writeByte(raster.length - offset); out.writeBytes(raster, offset, raster.length - offset); out.writeByte(0x00); //--------------------------------- // GIF Terminator out.writeString(';'); }; var bitOutputStream = function(out) { var _out = out; var _bitLength = 0; var _bitBuffer = 0; var _this = {}; _this.write = function(data, length) { if ( (data >>> length) != 0) { throw new Error('length over'); } while (_bitLength + length >= 8) { _out.writeByte(0xff & ( (data << _bitLength) | _bitBuffer) ); length -= (8 - _bitLength); data >>>= (8 - _bitLength); _bitBuffer = 0; _bitLength = 0; } _bitBuffer = (data << _bitLength) | _bitBuffer; _bitLength = _bitLength + length; }; _this.flush = function() { if (_bitLength > 0) { _out.writeByte(_bitBuffer); } }; return _this; }; var getLZWRaster = function(lzwMinCodeSize) { var clearCode = 1 << lzwMinCodeSize; var endCode = (1 << lzwMinCodeSize) + 1; var bitLength = lzwMinCodeSize + 1; // Setup LZWTable var table = lzwTable(); for (var i = 0; i < clearCode; i += 1) { table.add(String.fromCharCode(i) ); } table.add(String.fromCharCode(clearCode) ); table.add(String.fromCharCode(endCode) ); var byteOut = byteArrayOutputStream(); var bitOut = bitOutputStream(byteOut); // clear code bitOut.write(clearCode, bitLength); var dataIndex = 0; var s = String.fromCharCode(_data[dataIndex]); dataIndex += 1; while (dataIndex < _data.length) { var c = String.fromCharCode(_data[dataIndex]); dataIndex += 1; if (table.contains(s + c) ) { s = s + c; } else { bitOut.write(table.indexOf(s), bitLength); if (table.size() < 0xfff) { if (table.size() == (1 << bitLength) ) { bitLength += 1; } table.add(s + c); } s = c; } } bitOut.write(table.indexOf(s), bitLength); // end code bitOut.write(endCode, bitLength); bitOut.flush(); return byteOut.toByteArray(); }; var lzwTable = function() { var _map = {}; var _size = 0; var _this = {}; _this.add = function(key) { if (_this.contains(key) ) { throw new Error('dup key:' + key); } _map[key] = _size; _size += 1; }; _this.size = function() { return _size; }; _this.indexOf = function(key) { return _map[key]; }; _this.contains = function(key) { return typeof _map[key] != 'undefined'; }; return _this; }; return _this; }; var createImgTag = function(width, height, getPixel, alt) { var gif = gifImage(width, height); for (var y = 0; y < height; y += 1) { for (var x = 0; x < width; x += 1) { gif.setPixel(x, y, getPixel(x, y) ); } } var b = byteArrayOutputStream(); gif.write(b); var base64 = base64EncodeOutputStream(); var bytes = b.toByteArray(); for (var i = 0; i < bytes.length; i += 1) { base64.writeByte(bytes[i]); } base64.flush(); var img = ''; img += 'data:image/gif;base64,'; img += base64; return img; }; //--------------------------------------------------------------------- // returns qrcode function. var drawImg = function(text, options) { options = options || {}; var typeNumber = options.typeNumber || 4; var errorCorrectLevel = options.errorCorrectLevel || 'M'; var size = options.size || 500; var qr; try { qr = qrcode(typeNumber, errorCorrectLevel || 'M'); qr.addData(text); qr.make(); } catch (e) { if(typeNumber >= 40) { throw new Error('Text too long to encode'); } else { return drawImg(text, { size: size, errorCorrectLevel: errorCorrectLevel, typeNumber: typeNumber + 1 }); } } // calc cellsize and margin var cellsize = parseInt(size / qr.getModuleCount()); var margin = parseInt((size - qr.getModuleCount() * cellsize) / 2); return qr.createImgTag(cellsize, margin, size); }; module.exports = { drawImg: drawImg };
来自github地址:https://github.com/Pudon/weapp-qrcode-base64
