uniapp 小程序生成二维码 (兼容H5、微信小程序)

背景:
在购买电影票时，生成的取票码
普通文本生成二维码，识别到的值也是普通文本，例如：条形码，电影取票码内容实质都为普通文本；

平台区别：
1、jquery.qrcode,js （H5使用）
是一个用于生成二维码的 JavaScript 库，主要是通过获取 DOM 的标签,再通过 HTML5 Canvas 绘制而成,不依赖任何库。
小程序没有DOM概念，所以不能通用；
2、weapp-qrcode-canvas-2d
https://developers.weixin.qq.com/community/develop/article/doc/000e88e73a415835ed9b46d7956013

主要介绍一下小程序生成二维码插件：

介绍：
weapp-qrcode-canvas-2d是使用新版canvas-2d接口在微信小程序中生成二维码（外部二维码）的js包。canvas 2d 接口支持同层渲染且性能更佳，建议切换使用，可大幅提升速度；
仓库地址：

weapp-qrcode-canvas-2d【码云gitee】
weapp-qrcode-canvas-2d【github】

使用：
1、<canvas type="2d" style="width: 127px; height: 127px;position: fixed;top: -1000px;" id="myQrcode"></canvas>
注意：不能再v-if内，否则会导致找不到该节点
2、import drawQrcode from '@/common/qrcodeJs/qrcode.js';
注意：也可以npm安装 npm install weapp-qrcode-canvas-2d --save
3、这个是项目中实践使用的，没有使用叠加图片的

/**
* 生成二维码（没有使用叠加图片）
* text - 码值
* */
handleMakeQrcode(text) {return new Promise((resolve, reject) => {const query = uni.createSelectorQuery()query.select('#myQrcode').fields({node: true,size: true}).exec((res) => {// 获取node节点实例，目前仅微信，快手，京东小程序支持；// #ifdef MP-WEIXIN || MP-KUAISHOUlet canvas = res[0].node// #endif// 调用方法drawQrcode生成二维码drawQrcode({// #ifdef MP-WEIXIN || MP-KUAISHOUcanvas: canvas,// #endifcanvasId: 'myQrcode',width: 127,padding: 0,background: '#ffffff',foreground: '#000000',text: text,})// 获取临时路径uni.canvasToTempFilePath({canvasId: 'myQrcode',// #ifdef MP-WEIXIN || MP-KUAISHOUcanvas: canvas,// #endifx: 0,y: 0,width: 127,height: 127,destWidth: 127,destHeight: 127,success(res) {resolve(res.tempFilePath); // 临时路径},fail(res) {console.error(res);reject();}})});})
}

/*
* 文档中示例 - 有叠加图片的（在二维码中加logo）
*/
const query = wx.createSelectorQuery()query.select('#myQrcode').fields({node: true,size: true}).exec(async (res) => {var canvas = res[0].nodevar img = canvas.createImage();img.src = "/image/logo.png"img.onload = function () {// img.onload完成后才能调用 drawQrcode方法var options = {canvas: canvas,canvasId: 'myQrcode',width: 260,padding: 30,paddingColor: '#fff',background: '#fff',foreground: '#000000',text: 'https://gitee.com/WeiDoctor/weapp-qrcode-canvas-2d',image: {imageResource: img,width: 80, // 建议不要设置过大，以免影响扫码height: 80 // 建议不要设置过大，以免影响扫码round: true // Logo图片是否为圆形}}drawQrcode(options)// 获取临时路径（得到之后，想干嘛就干嘛了）wx.canvasToTempFilePath({x: 0,y: 0,width: 260,height: 260,destWidth: 600,destHeight: 600,canvasId: 'myQrcode',canvas: canvas,success(res) {console.log('二维码临时路径为：', res.tempFilePath)},fail(res) {console.error(res)}})};})

注意事项：
1. 因上面仓库的为微信端的Api，后续自己修改为uniapp跨平台的Api，已经测试过得支持微信端，H5端；
2. uni.createSelectorQuery() NodesRef 用于获取节点信息的对象
获取 Node 节点实例。目前支持 canvas 的获取，并且仅支持微信小程序，快手，京东小程序；
所以在不支持的地方不传canvas实例，
// 拿不到实例时，创建canvas,返回canvasContext
ctx = options._this ? uni.createCanvasContext && uni.createCanvasContext(options.canvasId, options._this) : uni.createCanvasContext &&uni.createCanvasContext(options.canvasId);

生成二维码需要用到的qrcode；

/*** weapp.qrcode.js v1.1.2 https://developers.weixin.qq.com/community/develop/article/doc/000e88e73a415835ed9b46d7956013*/(function(global, factory) {typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :typeof define === 'function' && define.amd ? define(factory) :(global.drawQrcode = factory());
}(this, (function() {'use strict';var hasOwn = Object.prototype.hasOwnProperty;var toStr = Object.prototype.toString;var defineProperty = Object.defineProperty;var gOPD = Object.getOwnPropertyDescriptor;var isArray = function isArray(arr) {if (typeof Array.isArray === 'function') {return Array.isArray(arr);}return toStr.call(arr) === '[object Array]';};var isPlainObject = function isPlainObject(obj) {if (!obj || toStr.call(obj) !== '[object Object]') {return false;}var hasOwnConstructor = hasOwn.call(obj, 'constructor');var hasIsPrototypeOf = obj.constructor && obj.constructor.prototype && hasOwn.call(obj.constructor.prototype, 'isPrototypeOf');// Not own constructor property must be Objectif (obj.constructor && !hasOwnConstructor && !hasIsPrototypeOf) {return false;}// Own properties are enumerated firstly, so to speed up,// if last one is own, then all properties are own.var key;for (key in obj) {/**/ }return typeof key === 'undefined' || hasOwn.call(obj, key);};// If name is '__proto__', and Object.defineProperty is available, define __proto__ as an own property on targetvar setProperty = function setProperty(target, options) {if (defineProperty && options.name === '__proto__') {defineProperty(target, options.name, {enumerable: true,configurable: true,value: options.newValue,writable: true});} else {target[options.name] = options.newValue;}};// Return undefined instead of __proto__ if '__proto__' is not an own propertyvar getProperty = function getProperty(obj, name) {if (name === '__proto__') {if (!hasOwn.call(obj, name)) {return void 0;} else if (gOPD) {// In early versions of node, obj['__proto__'] is buggy when obj has// __proto__ as an own property. Object.getOwnPropertyDescriptor() works.return gOPD(obj, name).value;}}return obj[name];};var extend = function extend() {var options, name, src, copy, copyIsArray, clone;var target = arguments[0];var i = 1;var length = arguments.length;var deep = false;// Handle a deep copy situationif (typeof target === 'boolean') {deep = target;target = arguments[1] || {};// skip the boolean and the targeti = 2;}if (target == null || (typeof target !== 'object' && typeof target !== 'function')) {target = {};}for (; i < length; ++i) {options = arguments[i];// Only deal with non-null/undefined valuesif (options != null) {// Extend the base objectfor (name in options) {src = getProperty(target, name);copy = getProperty(options, name);// Prevent never-ending loopif (target !== copy) {// Recurse if we're merging plain objects or arraysif (deep && copy && (isPlainObject(copy) || (copyIsArray = isArray(copy)))) {if (copyIsArray) {copyIsArray = false;clone = src && isArray(src) ? src : [];} else {clone = src && isPlainObject(src) ? src : {};}// Never move original objects, clone themsetProperty(target, {name: name,newValue: extend(deep, clone, copy)});// Don't bring in undefined values} else if (typeof copy !== 'undefined') {setProperty(target, {name: name,newValue: copy});}}}}}// Return the modified objectreturn target;};//---------------------------------------------------------------------// QRCode 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////---------------------------------------------------------------------//---------------------------------------------------------------------// QR8bitByte//---------------------------------------------------------------------function QR8bitByte(data) {this.mode = QRMode.MODE_8BIT_BYTE;this.data = data;}QR8bitByte.prototype = {getLength: function(buffer) {return this.data.length;},write: function(buffer) {for (var i = 0; i < this.data.length; i++) {// not JIS ...buffer.put(this.data.charCodeAt(i), 8);}}};//---------------------------------------------------------------------// QRCode//---------------------------------------------------------------------function QRCode(typeNumber, errorCorrectLevel) {this.typeNumber = typeNumber;this.errorCorrectLevel = errorCorrectLevel;this.modules = null;this.moduleCount = 0;this.dataCache = null;this.dataList = new Array();}QRCode.prototype = {addData: function(data) {var newData = new QR8bitByte(data);this.dataList.push(newData);this.dataCache = null;},isDark: function(row, col) {if (row < 0 || this.moduleCount <= row || col < 0 || this.moduleCount <= col) {throw new Error(row + "," + col);}return this.modules[row][col];},getModuleCount: function() {return this.moduleCount;},make: function() {// Calculate automatically typeNumber if provided is < 1if (this.typeNumber < 1) {var typeNumber = 1;for (typeNumber = 1; typeNumber < 40; typeNumber++) {var rsBlocks = QRRSBlock.getRSBlocks(typeNumber, this.errorCorrectLevel);var buffer = new QRBitBuffer();var totalDataCount = 0;for (var i = 0; i < rsBlocks.length; i++) {totalDataCount += rsBlocks[i].dataCount;}for (var i = 0; i < this.dataList.length; i++) {var data = this.dataList[i];buffer.put(data.mode, 4);buffer.put(data.getLength(), QRUtil.getLengthInBits(data.mode, typeNumber));data.write(buffer);}if (buffer.getLengthInBits() <= totalDataCount * 8) break;}this.typeNumber = typeNumber;}this.makeImpl(false, this.getBestMaskPattern());},makeImpl: function(test, maskPattern) {this.moduleCount = this.typeNumber * 4 + 17;this.modules = new Array(this.moduleCount);for (var row = 0; row < this.moduleCount; row++) {this.modules[row] = new Array(this.moduleCount);for (var col = 0; col < this.moduleCount; col++) {this.modules[row][col] = null; //(col + row) % 3;}}this.setupPositionProbePattern(0, 0);this.setupPositionProbePattern(this.moduleCount - 7, 0);this.setupPositionProbePattern(0, this.moduleCount - 7);this.setupPositionAdjustPattern();this.setupTimingPattern();this.setupTypeInfo(test, maskPattern);if (this.typeNumber >= 7) {this.setupTypeNumber(test);}if (this.dataCache == null) {this.dataCache = QRCode.createData(this.typeNumber, this.errorCorrectLevel, this.dataList);}this.mapData(this.dataCache, maskPattern);},setupPositionProbePattern: function(row, col) {for (var r = -1; r <= 7; r++) {if (row + r <= -1 || this.moduleCount <= row + r) continue;for (var c = -1; c <= 7; c++) {if (col + c <= -1 || this.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) {this.modules[row + r][col + c] = true;} else {this.modules[row + r][col + c] = false;}}}},getBestMaskPattern: function() {var minLostPoint = 0;var pattern = 0;for (var i = 0; i < 8; i++) {this.makeImpl(true, i);var lostPoint = QRUtil.getLostPoint(this);if (i == 0 || minLostPoint > lostPoint) {minLostPoint = lostPoint;pattern = i;}}return pattern;},createMovieClip: function(target_mc, instance_name, depth) {var qr_mc = target_mc.createEmptyMovieClip(instance_name, depth);var cs = 1;this.make();for (var row = 0; row < this.modules.length; row++) {var y = row * cs;for (var col = 0; col < this.modules[row].length; col++) {var x = col * cs;var dark = this.modules[row][col];if (dark) {qr_mc.beginFill(0, 100);qr_mc.moveTo(x, y);qr_mc.lineTo(x + cs, y);qr_mc.lineTo(x + cs, y + cs);qr_mc.lineTo(x, y + cs);qr_mc.endFill();}}}return qr_mc;},setupTimingPattern: function() {for (var r = 8; r < this.moduleCount - 8; r++) {if (this.modules[r][6] != null) {continue;}this.modules[r][6] = r % 2 == 0;}for (var c = 8; c < this.moduleCount - 8; c++) {if (this.modules[6][c] != null) {continue;}this.modules[6][c] = c % 2 == 0;}},setupPositionAdjustPattern: function() {var pos = QRUtil.getPatternPosition(this.typeNumber);for (var i = 0; i < pos.length; i++) {for (var j = 0; j < pos.length; j++) {var row = pos[i];var col = pos[j];if (this.modules[row][col] != null) {continue;}for (var r = -2; r <= 2; r++) {for (var c = -2; c <= 2; c++) {if (r == -2 || r == 2 || c == -2 || c == 2 || r == 0 && c == 0) {this.modules[row + r][col + c] = true;} else {this.modules[row + r][col + c] = false;}}}}}},setupTypeNumber: function(test) {var bits = QRUtil.getBCHTypeNumber(this.typeNumber);for (var i = 0; i < 18; i++) {var mod = !test && (bits >> i & 1) == 1;this.modules[Math.floor(i / 3)][i % 3 + this.moduleCount - 8 - 3] = mod;}for (var i = 0; i < 18; i++) {var mod = !test && (bits >> i & 1) == 1;this.modules[i % 3 + this.moduleCount - 8 - 3][Math.floor(i / 3)] = mod;}},setupTypeInfo: function(test, maskPattern) {var data = this.errorCorrectLevel << 3 | maskPattern;var bits = QRUtil.getBCHTypeInfo(data);// vertical   for (var i = 0; i < 15; i++) {var mod = !test && (bits >> i & 1) == 1;if (i < 6) {this.modules[i][8] = mod;} else if (i < 8) {this.modules[i + 1][8] = mod;} else {this.modules[this.moduleCount - 15 + i][8] = mod;}}// horizontalfor (var i = 0; i < 15; i++) {var mod = !test && (bits >> i & 1) == 1;if (i < 8) {this.modules[8][this.moduleCount - i - 1] = mod;} else if (i < 9) {this.modules[8][15 - i - 1 + 1] = mod;} else {this.modules[8][15 - i - 1] = mod;}}// fixed modulethis.modules[this.moduleCount - 8][8] = !test;},mapData: function(data, maskPattern) {var inc = -1;var row = this.moduleCount - 1;var bitIndex = 7;var byteIndex = 0;for (var col = this.moduleCount - 1; col > 0; col -= 2) {if (col == 6) col--;while (true) {for (var c = 0; c < 2; c++) {if (this.modules[row][col - c] == null) {var dark = false;if (byteIndex < data.length) {dark = (data[byteIndex] >>> bitIndex & 1) == 1;}var mask = QRUtil.getMask(maskPattern, row, col - c);if (mask) {dark = !dark;}this.modules[row][col - c] = dark;bitIndex--;if (bitIndex == -1) {byteIndex++;bitIndex = 7;}}}row += inc;if (row < 0 || this.moduleCount <= row) {row -= inc;inc = -inc;break;}}}}};QRCode.PAD0 = 0xEC;QRCode.PAD1 = 0x11;QRCode.createData = function(typeNumber, errorCorrectLevel, dataList) {var rsBlocks = QRRSBlock.getRSBlocks(typeNumber, errorCorrectLevel);var buffer = new QRBitBuffer();for (var i = 0; i < dataList.length; i++) {var data = dataList[i];buffer.put(data.mode, 4);buffer.put(data.getLength(), QRUtil.getLengthInBits(data.mode, typeNumber));data.write(buffer);}// calc num max data.var totalDataCount = 0;for (var i = 0; i < rsBlocks.length; i++) {totalDataCount += rsBlocks[i].dataCount;}if (buffer.getLengthInBits() > totalDataCount * 8) {throw new Error("code length overflow. (" + buffer.getLengthInBits() + ">" +totalDataCount * 8 + ")");}// end codeif (buffer.getLengthInBits() + 4 <= totalDataCount * 8) {buffer.put(0, 4);}// paddingwhile (buffer.getLengthInBits() % 8 != 0) {buffer.putBit(false);}// paddingwhile (true) {if (buffer.getLengthInBits() >= totalDataCount * 8) {break;}buffer.put(QRCode.PAD0, 8);if (buffer.getLengthInBits() >= totalDataCount * 8) {break;}buffer.put(QRCode.PAD1, 8);}return QRCode.createBytes(buffer, rsBlocks);};QRCode.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++) {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++) {dcdata[r][i] = 0xff & buffer.buffer[i + offset];}offset += dcCount;var rsPoly = QRUtil.getErrorCorrectPolynomial(ecCount);var rawPoly = new 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++) {var modIndex = i + modPoly.getLength() - ecdata[r].length;ecdata[r][i] = modIndex >= 0 ? modPoly.get(modIndex) : 0;}}var totalCodeCount = 0;for (var i = 0; i < rsBlocks.length; i++) {totalCodeCount += rsBlocks[i].totalCount;}var data = new Array(totalCodeCount);var index = 0;for (var i = 0; i < maxDcCount; i++) {for (var r = 0; r < rsBlocks.length; r++) {if (i < dcdata[r].length) {data[index++] = dcdata[r][i];}}}for (var i = 0; i < maxEcCount; i++) {for (var r = 0; r < rsBlocks.length; r++) {if (i < ecdata[r].length) {data[index++] = ecdata[r][i];}}}return data;};//---------------------------------------------------------------------// 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 = {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]],G15: 1 << 10 | 1 << 8 | 1 << 5 | 1 << 4 | 1 << 2 | 1 << 1 | 1 << 0,G18: 1 << 12 | 1 << 11 | 1 << 10 | 1 << 9 | 1 << 8 | 1 << 5 | 1 << 2 | 1 << 0,G15_MASK: 1 << 14 | 1 << 12 | 1 << 10 | 1 << 4 | 1 << 1,getBCHTypeInfo: function(data) {var d = data << 10;while (QRUtil.getBCHDigit(d) - QRUtil.getBCHDigit(QRUtil.G15) >= 0) {d ^= QRUtil.G15 << QRUtil.getBCHDigit(d) - QRUtil.getBCHDigit(QRUtil.G15);}return (data << 10 | d) ^ QRUtil.G15_MASK;},getBCHTypeNumber: function(data) {var d = data << 12;while (QRUtil.getBCHDigit(d) - QRUtil.getBCHDigit(QRUtil.G18) >= 0) {d ^= QRUtil.G18 << QRUtil.getBCHDigit(d) - QRUtil.getBCHDigit(QRUtil.G18);}return data << 12 | d;},getBCHDigit: function(data) {var digit = 0;while (data != 0) {digit++;data >>>= 1;}return digit;},getPatternPosition: function(typeNumber) {return QRUtil.PATTERN_POSITION_TABLE[typeNumber - 1];},getMask: function(maskPattern, i, j) {switch (maskPattern) {case QRMaskPattern.PATTERN000:return (i + j) % 2 == 0;case QRMaskPattern.PATTERN001:return i % 2 == 0;case QRMaskPattern.PATTERN010:return j % 3 == 0;case QRMaskPattern.PATTERN011:return (i + j) % 3 == 0;case QRMaskPattern.PATTERN100:return (Math.floor(i / 2) + Math.floor(j / 3)) % 2 == 0;case QRMaskPattern.PATTERN101:return i * j % 2 + i * j % 3 == 0;case QRMaskPattern.PATTERN110:return (i * j % 2 + i * j % 3) % 2 == 0;case QRMaskPattern.PATTERN111:return (i * j % 3 + (i + j) % 2) % 2 == 0;default:throw new Error("bad maskPattern:" + maskPattern);}},getErrorCorrectPolynomial: function(errorCorrectLength) {var a = new QRPolynomial([1], 0);for (var i = 0; i < errorCorrectLength; i++) {a = a.multiply(new QRPolynomial([1, QRMath.gexp(i)], 0));}return a;},getLengthInBits: function(mode, type) {if (1 <= type && type < 10) {// 1 - 9switch (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 - 26switch (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 - 40switch (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);}},getLostPoint: function(qrCode) {var moduleCount = qrCode.getModuleCount();var lostPoint = 0;// LEVEL1for (var row = 0; row < moduleCount; row++) {for (var col = 0; col < moduleCount; col++) {var sameCount = 0;var dark = qrCode.isDark(row, col);for (var r = -1; r <= 1; r++) {if (row + r < 0 || moduleCount <= row + r) {continue;}for (var c = -1; c <= 1; c++) {if (col + c < 0 || moduleCount <= col + c) {continue;}if (r == 0 && c == 0) {continue;}if (dark == qrCode.isDark(row + r, col + c)) {sameCount++;}}}if (sameCount > 5) {lostPoint += 3 + sameCount - 5;}}}// LEVEL2for (var row = 0; row < moduleCount - 1; row++) {for (var col = 0; col < moduleCount - 1; col++) {var count = 0;if (qrCode.isDark(row, col)) count++;if (qrCode.isDark(row + 1, col)) count++;if (qrCode.isDark(row, col + 1)) count++;if (qrCode.isDark(row + 1, col + 1)) count++;if (count == 0 || count == 4) {lostPoint += 3;}}}// LEVEL3for (var row = 0; row < moduleCount; row++) {for (var col = 0; col < moduleCount - 6; col++) {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++) {for (var row = 0; row < moduleCount - 6; row++) {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;}}}// LEVEL4var darkCount = 0;for (var col = 0; col < moduleCount; col++) {for (var row = 0; row < moduleCount; row++) {if (qrCode.isDark(row, col)) {darkCount++;}}}var ratio = Math.abs(100 * darkCount / moduleCount / moduleCount - 50) / 5;lostPoint += ratio * 10;return lostPoint;}};//---------------------------------------------------------------------// QRMath//---------------------------------------------------------------------var QRMath = {glog: function(n) {if (n < 1) {throw new Error("glog(" + n + ")");}return QRMath.LOG_TABLE[n];},gexp: function(n) {while (n < 0) {n += 255;}while (n >= 256) {n -= 255;}return QRMath.EXP_TABLE[n];},EXP_TABLE: new Array(256),LOG_TABLE: new Array(256)};for (var i = 0; i < 8; i++) {QRMath.EXP_TABLE[i] = 1 << i;}for (var i = 8; i < 256; i++) {QRMath.EXP_TABLE[i] = QRMath.EXP_TABLE[i - 4] ^ QRMath.EXP_TABLE[i - 5] ^ QRMath.EXP_TABLE[i - 6] ^QRMath.EXP_TABLE[i - 8];}for (var i = 0; i < 255; i++) {QRMath.LOG_TABLE[QRMath.EXP_TABLE[i]] = i;}//---------------------------------------------------------------------// QRPolynomial//---------------------------------------------------------------------function QRPolynomial(num, shift) {if (num.length == undefined) {throw new Error(num.length + "/" + shift);}var offset = 0;while (offset < num.length && num[offset] == 0) {offset++;}this.num = new Array(num.length - offset + shift);for (var i = 0; i < num.length - offset; i++) {this.num[i] = num[i + offset];}}QRPolynomial.prototype = {get: function(index) {return this.num[index];},getLength: function() {return this.num.length;},multiply: function(e) {var num = new Array(this.getLength() + e.getLength() - 1);for (var i = 0; i < this.getLength(); i++) {for (var j = 0; j < e.getLength(); j++) {num[i + j] ^= QRMath.gexp(QRMath.glog(this.get(i)) + QRMath.glog(e.get(j)));}}return new QRPolynomial(num, 0);},mod: function(e) {if (this.getLength() - e.getLength() < 0) {return this;}var ratio = QRMath.glog(this.get(0)) - QRMath.glog(e.get(0));var num = new Array(this.getLength());for (var i = 0; i < this.getLength(); i++) {num[i] = this.get(i);}for (var i = 0; i < e.getLength(); i++) {num[i] ^= QRMath.gexp(QRMath.glog(e.get(i)) + ratio);}// recursive callreturn new QRPolynomial(num, 0).mod(e);}};//---------------------------------------------------------------------// QRRSBlock//---------------------------------------------------------------------function QRRSBlock(totalCount, dataCount) {this.totalCount = totalCount;this.dataCount = dataCount;}QRRSBlock.RS_BLOCK_TABLE = [// L// M// Q// H// 1[1, 26, 19],[1, 26, 16],[1, 26, 13],[1, 26, 9],// 2[1, 44, 34],[1, 44, 28],[1, 44, 22],[1, 44, 16],// 3[1, 70, 55],[1, 70, 44],[2, 35, 17],[2, 35, 13],// 4    [1, 100, 80],[2, 50, 32],[2, 50, 24],[4, 25, 9],// 5[1, 134, 108],[2, 67, 43],[2, 33, 15, 2, 34, 16],[2, 33, 11, 2, 34, 12],// 6[2, 86, 68],[4, 43, 27],[4, 43, 19],[4, 43, 15],// 7    [2, 98, 78],[4, 49, 31],[2, 32, 14, 4, 33, 15],[4, 39, 13, 1, 40, 14],// 8[2, 121, 97],[2, 60, 38, 2, 61, 39],[4, 40, 18, 2, 41, 19],[4, 40, 14, 2, 41, 15],// 9[2, 146, 116],[3, 58, 36, 2, 59, 37],[4, 36, 16, 4, 37, 17],[4, 36, 12, 4, 37, 13],// 10   [2, 86, 68, 2, 87, 69],[4, 69, 43, 1, 70, 44],[6, 43, 19, 2, 44, 20],[6, 43, 15, 2, 44, 16],// 11[4, 101, 81],[1, 80, 50, 4, 81, 51],[4, 50, 22, 4, 51, 23],[3, 36, 12, 8, 37, 13],// 12[2, 116, 92, 2, 117, 93],[6, 58, 36, 2, 59, 37],[4, 46, 20, 6, 47, 21],[7, 42, 14, 4, 43, 15],// 13[4, 133, 107],[8, 59, 37, 1, 60, 38],[8, 44, 20, 4, 45, 21],[12, 33, 11, 4, 34, 12],// 14[3, 145, 115, 1, 146, 116],[4, 64, 40, 5, 65, 41],[11, 36, 16, 5, 37, 17],[11, 36, 12, 5, 37, 13],// 15[5, 109, 87, 1, 110, 88],[5, 65, 41, 5, 66, 42],[5, 54, 24, 7, 55, 25],[11, 36, 12],// 16[5, 122, 98, 1, 123, 99],[7, 73, 45, 3, 74, 46],[15, 43, 19, 2, 44, 20],[3, 45, 15, 13, 46, 16],// 17[1, 135, 107, 5, 136, 108],[10, 74, 46, 1, 75, 47],[1, 50, 22, 15, 51, 23],[2, 42, 14, 17, 43, 15],// 18[5, 150, 120, 1, 151, 121],[9, 69, 43, 4, 70, 44],[17, 50, 22, 1, 51, 23],[2, 42, 14, 19, 43, 15],// 19[3, 141, 113, 4, 142, 114],[3, 70, 44, 11, 71, 45],[17, 47, 21, 4, 48, 22],[9, 39, 13, 16, 40, 14],// 20[3, 135, 107, 5, 136, 108],[3, 67, 41, 13, 68, 42],[15, 54, 24, 5, 55, 25],[15, 43, 15, 10, 44, 16],// 21[4, 144, 116, 4, 145, 117],[17, 68, 42],[17, 50, 22, 6, 51, 23],[19, 46, 16, 6, 47, 17],// 22[2, 139, 111, 7, 140, 112],[17, 74, 46],[7, 54, 24, 16, 55, 25],[34, 37, 13],// 23[4, 151, 121, 5, 152, 122],[4, 75, 47, 14, 76, 48],[11, 54, 24, 14, 55, 25],[16, 45, 15, 14, 46, 16],// 24[6, 147, 117, 4, 148, 118],[6, 73, 45, 14, 74, 46],[11, 54, 24, 16, 55, 25],[30, 46, 16, 2, 47, 17],// 25[8, 132, 106, 4, 133, 107],[8, 75, 47, 13, 76, 48],[7, 54, 24, 22, 55, 25],[22, 45, 15, 13, 46, 16],// 26[10, 142, 114, 2, 143, 115],[19, 74, 46, 4, 75, 47],[28, 50, 22, 6, 51, 23],[33, 46, 16, 4, 47, 17],// 27[8, 152, 122, 4, 153, 123],[22, 73, 45, 3, 74, 46],[8, 53, 23, 26, 54, 24],[12, 45, 15, 28, 46, 16],// 28[3, 147, 117, 10, 148, 118],[3, 73, 45, 23, 74, 46],[4, 54, 24, 31, 55, 25],[11, 45, 15, 31, 46, 16],// 29[7, 146, 116, 7, 147, 117],[21, 73, 45, 7, 74, 46],[1, 53, 23, 37, 54, 24],[19, 45, 15, 26, 46, 16],// 30[5, 145, 115, 10, 146, 116],[19, 75, 47, 10, 76, 48],[15, 54, 24, 25, 55, 25],[23, 45, 15, 25, 46, 16],// 31[13, 145, 115, 3, 146, 116],[2, 74, 46, 29, 75, 47],[42, 54, 24, 1, 55, 25],[23, 45, 15, 28, 46, 16],// 32[17, 145, 115],[10, 74, 46, 23, 75, 47],[10, 54, 24, 35, 55, 25],[19, 45, 15, 35, 46, 16],// 33[17, 145, 115, 1, 146, 116],[14, 74, 46, 21, 75, 47],[29, 54, 24, 19, 55, 25],[11, 45, 15, 46, 46, 16],// 34[13, 145, 115, 6, 146, 116],[14, 74, 46, 23, 75, 47],[44, 54, 24, 7, 55, 25],[59, 46, 16, 1, 47, 17],// 35[12, 151, 121, 7, 152, 122],[12, 75, 47, 26, 76, 48],[39, 54, 24, 14, 55, 25],[22, 45, 15, 41, 46, 16],// 36[6, 151, 121, 14, 152, 122],[6, 75, 47, 34, 76, 48],[46, 54, 24, 10, 55, 25],[2, 45, 15, 64, 46, 16],// 37[17, 152, 122, 4, 153, 123],[29, 74, 46, 14, 75, 47],[49, 54, 24, 10, 55, 25],[24, 45, 15, 46, 46, 16],// 38[4, 152, 122, 18, 153, 123],[13, 74, 46, 32, 75, 47],[48, 54, 24, 14, 55, 25],[42, 45, 15, 32, 46, 16],// 39[20, 147, 117, 4, 148, 118],[40, 75, 47, 7, 76, 48],[43, 54, 24, 22, 55, 25],[10, 45, 15, 67, 46, 16],// 40[19, 148, 118, 6, 149, 119],[18, 75, 47, 31, 76, 48],[34, 54, 24, 34, 55, 25],[20, 45, 15, 61, 46, 16]];QRRSBlock.getRSBlocks = function(typeNumber, errorCorrectLevel) {var rsBlock = QRRSBlock.getRsBlockTable(typeNumber, errorCorrectLevel);if (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++) {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++) {list.push(new QRRSBlock(totalCount, dataCount));}}return list;};QRRSBlock.getRsBlockTable = function(typeNumber, errorCorrectLevel) {switch (errorCorrectLevel) {case QRErrorCorrectLevel.L:return QRRSBlock.RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 0];case QRErrorCorrectLevel.M:return QRRSBlock.RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 1];case QRErrorCorrectLevel.Q:return QRRSBlock.RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 2];case QRErrorCorrectLevel.H:return QRRSBlock.RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 3];default:return undefined;}};//---------------------------------------------------------------------// QRBitBuffer//---------------------------------------------------------------------function QRBitBuffer() {this.buffer = new Array();this.length = 0;}QRBitBuffer.prototype = {get: function(index) {var bufIndex = Math.floor(index / 8);return (this.buffer[bufIndex] >>> 7 - index % 8 & 1) == 1;},put: function(num, length) {for (var i = 0; i < length; i++) {this.putBit((num >>> length - i - 1 & 1) == 1);}},getLengthInBits: function() {return this.length;},putBit: function(bit) {var bufIndex = Math.floor(this.length / 8);if (this.buffer.length <= bufIndex) {this.buffer.push(0);}if (bit) {this.buffer[bufIndex] |= 0x80 >>> this.length % 8;}this.length++;}};// support Chinesefunction utf16to8(str) {var out, i, len, c;out = '';len = str.length;for (i = 0; i < len; i++) {c = str.charCodeAt(i);if (c >= 0x0001 && c <= 0x007F) {out += str.charAt(i);} else if (c > 0x07FF) {out += String.fromCharCode(0xE0 | c >> 12 & 0x0F);out += String.fromCharCode(0x80 | c >> 6 & 0x3F);out += String.fromCharCode(0x80 | c >> 0 & 0x3F);} else {out += String.fromCharCode(0xC0 | c >> 6 & 0x1F);out += String.fromCharCode(0x80 | c >> 0 & 0x3F);}}return out;}function drawQrcode(options, debug) {options = options || {};options = extend(true, {canvasId: 'myQrcode',// canvas: canvas,text: '爱一个人就要勇敢说出来',x: 0,y: 0,width: 260,height: 260,padding: 20,// paddingColor: '#ffffff', // 默认与background一致typeNumber: -1,correctLevel: QRErrorCorrectLevel.H,background: '#ffffff',foreground: '#000000',image: {imageResource: '',width: 80,height: 80,round: true}}, options);if (!options.canvasId && !options.canvas) {console.warn('please set canvasId or canvas!');return;}if (!options.paddingColor) options.paddingColor = options.background;if (debug) {var qrcode = new QRCode(options.typeNumber, options.correctLevel);qrcode.addData(utf16to8(options.text));qrcode.make();return new Promise(function(resolve, reject) {resolve(qrcode);});} else {return new Promise(function(resolve, reject) {return resolve(createCanvas());});}function createCanvas() {// create the qrcode itselfvar qrcode = new QRCode(options.typeNumber, options.correctLevel);qrcode.addData(utf16to8(options.text));qrcode.make();const dpr = uni.getSystemInfoSync().pixelRatio;// 获取canvas实例 兼容拿不到canvas实例的情况；var ctx;var width;var canvas = options.canvas;if (canvas) {ctx = canvas.getContext('2d');canvas.width = options.width * dpr;canvas.height = options.width * dpr;width = options.width * dpr;// 背景色ctx.fillStyle = options.paddingColor;ctx.fillRect(0, 0, width + options.padding * 2, width + options.padding * 2);var tileW = (width - options.padding * 2) / qrcode.getModuleCount();var tileH = (width - options.padding * 2) / qrcode.getModuleCount();// 开始画二维码for (var row = 0; row < qrcode.getModuleCount(); row++) {for (var col = 0; col < qrcode.getModuleCount(); col++) {ctx.fillStyle = qrcode.isDark(row, col) ? options.foreground : options.background;var w = Math.ceil((col + 1) * tileW) - Math.floor(col * tileW);var h = Math.ceil((row + 1) * tileW) - Math.floor(row * tileW);ctx.fillRect(Math.round(col * tileW) + options.padding, Math.round(row * tileH) +options.padding, w, h);}}if (options.image.imageResource) {const imgW = options.image.width * dpr;const imgH = options.image.height * dpr;const dx = (width - imgW) / 2;const dy = (width - imgH) / 2;if (options.image.round) {// Logo边框const imgW2 = options.image.width * dpr + 30;const dx2 = (width - imgW2) / 2;const r2 = imgW2 / 2;const cx2 = dx2 + r2;ctx.beginPath();ctx.arc(cx2, cx2, r2, 0, 2 * Math.PI);ctx.fillStyle = '#ffffff';ctx.fill();ctx.restore();// 画Logoconst r = imgW / 2;const cx = dx + r;const cy = dy + r;ctx.beginPath();ctx.arc(cx, cy, r, 0, 2 * Math.PI);ctx.clip();ctx.drawImage(options.image.imageResource, dx, dy, imgW, imgW);ctx.restore();} else {ctx.drawImage(options.image.imageResource, dx, dy, imgW, imgH);ctx.restore();}}return ctx;} else {// 拿不到实例时，创建canvas,返回canvasContextctx = options._this ? uni.createCanvasContext && uni.createCanvasContext(options.canvasId,options._this) : uni.createCanvasContext && uni.createCanvasContext(options.canvasId);width = options.width;var tileW = (width - options.padding * 2) / qrcode.getModuleCount();var tileH = (width - options.padding * 2) / qrcode.getModuleCount();// draw in the canvasfor (var row = 0; row < qrcode.getModuleCount(); row++) {for (var col = 0; col < qrcode.getModuleCount(); col++) {ctx.fillStyle = qrcode.isDark(row, col) ? options.foreground : options.background;var w = Math.ceil((col + 1) * tileW) - Math.floor(col * tileW);var h = Math.ceil((row + 1) * tileW) - Math.floor(row * tileW);ctx.fillRect(Math.round(col * tileW) + options.padding, Math.round(row * tileH) +options.padding, w, h);}}if (options.image.imageResource) {ctx.drawImage(options.image.imageResource, options.image.dx, options.image.dy, options.image.dWidth, options.image.dHeight);}ctx.draw(false, function(e) {options.callback && options.callback(e);});}}}return drawQrcode;})));

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