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微信小程序生成二维码

本文主要是介绍微信小程序生成二维码,对大家解决编程问题具有一定的参考价值,需要的程序猿们随着小编来一起学习吧!

1、需求:项目需求是获取一个通行码get链接,需要转化成二维码,用户扫码之后发起请求进行远程开门。

2、思路:在微信小程序中生成二维码比较好用的是weapp-qrcode,去到官网https://github.com/yingye/weapp-qrcode,复制dist 目录下,weapp.qrcode.esm.js文件,粘贴到小程序项目,就可以用了。

3、实现:

wxml

 <canvas class="myQrcode" style="width: 250rpx; height: 250rpx;" canvas-id="myQrcode"></canvas>

js

//引用
const qrcode= require('../../../utils/weapp.qrcode.esm.js')
//方法
  setQrcode(){
    qrcode({
      width: 125,
      height: 125,
      canvasId: 'myQrcode',
      text: '需要转化的链接',
    })
  },

 

4、效果:

 5、以下是方便使用

/**
 * weapp.qrcode.js v1.0.0 (https://github.com/yingye/weapp-qrcode#readme)
 */

(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 Object
    if (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 target
  var 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 property
  var 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 situation
    if (typeof target === 'boolean') {
      deep = target;
      target = arguments[1] || {};
      // skip the boolean and the target
      i = 2;
    }
    if (target == null || (typeof target !== 'object' && typeof target !== 'function')) {
      target = {};
    }

    for (; i < length; ++i) {
      options = arguments[i];
      // Only deal with non-null/undefined values
      if (options != null) {
        // Extend the base object
        for (name in options) {
          src = getProperty(target, name);
          copy = getProperty(options, name);

          // Prevent never-ending loop
          if (target !== copy) {
            // Recurse if we're merging plain objects or arrays
            if (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 them
              setProperty(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 object
    return 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 < 1
      if (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;
        }
      }

      // horizontal
      for (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 module
      this.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 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(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 - 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);
      }
    },

    getLostPoint: function (qrCode) {

      var moduleCount = qrCode.getModuleCount();

      var lostPoint = 0;

      // LEVEL1

      for (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;
          }
        }
      }

      // LEVEL2

      for (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;
          }
        }
      }

      // LEVEL3

      for (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;
          }
        }
      }

      // LEVEL4

      var 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 call
      return 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 Chinese
  function 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) {
    options = options || {};
    options = extend(true, {
      width: 256,
      height: 256,
      x: 0,
      y: 0,
      typeNumber: -1,
      correctLevel: QRErrorCorrectLevel.H,
      background: '#ffffff',
      foreground: '#000000',
      image: {
        imageResource: '',
        dx: 0,
        dy: 0,
        dWidth: 100,
        dHeight: 100
      }
    }, options);

    if (!options.canvasId && !options.ctx) {
      console.warn('please set canvasId or ctx!');
      return;
    }

    createCanvas();

    function createCanvas() {
      // create the qrcode itself
      var qrcode = new QRCode(options.typeNumber, options.correctLevel);
      qrcode.addData(utf16to8(options.text));
      qrcode.make();

      // get canvas context
      var ctx;
      if (options.ctx) {
        ctx = options.ctx;
      } else {
        ctx = options._this ? wx.createCanvasContext && wx.createCanvasContext(options.canvasId, options._this) : wx.createCanvasContext && wx.createCanvasContext(options.canvasId);
      }

      // compute tileW/tileH based on options.width/options.height
      var tileW = options.width / qrcode.getModuleCount();
      var tileH = options.height / qrcode.getModuleCount();

      // draw in the canvas
      for (var row = 0; row < qrcode.getModuleCount(); row++) {
        for (var col = 0; col < qrcode.getModuleCount(); col++) {
          var style = qrcode.isDark(row, col) ? options.foreground : options.background;
          ctx.setFillStyle(style);
          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.x, Math.round(row * tileH) + options.y, 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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