14--微信小程序 二维码（组件）canvas

页面：

<view class="container">
  <view class="header">
    <text class="code-tit">班级编号:</text>
    <text class="code-num">{{classid}}</text>
  </view>
  <view class="qrcode-box">
    <canvas class="canvas" style="width:{{qrcode_w}}px; height:{{qrcode_w}}px;" canvas-id="couponQrcode"></canvas>
  </view>
  <view class="btn">
    <button bindtap="save" class="save" type="submit" size="mini">保存</button>
  </view>
  <tui-icon class="close" name="shut" size="30" bindtap="close"></tui-icon>
</view>

js：

const qrCode = require('../../../utils/weapp-qrcode')

Component({
  properties: {
    classid: {
      type: String,
      value: ""
    }
  },

  data: {
    qrcode_w: 150
  },
  lifetimes: {
    attached: function() {
      let qrcode = this.couponQrcode(this.data.classid, 'couponQrcode')

      this.setData({
        qrcode
      })
      // Console.log(qrcode)
    }
  },

  methods: {
    couponQrcode(text, canvasId) {
      let qrcode = new qrCode(canvasId, {
        text: text,
        width: this.data.qrcode_w,
        height: this.data.qrcode_w,
        colorDark: "#333333",
        colorLight: "#ffffff",
        correctLevel: qrCode.CorrectLevel.H,
        usingIn: this
      });
      return qrcode
    },
    //关闭
    close: function() {
      this.triggerEvent('close', {})
    },
    //保存
    save:function() {
      this.data.qrcode.exportImage(function(res) {
        console.log(res)
        if (res.tempFilePath) {
          wx.saveImageToPhotosAlbum({
            filePath: res.tempFilePath,
            success: res => {

            }
          })
        } else {
          wx.showToast({
            title: res.errMsg,
            icon: "none"
          })
        }

      })
    } //save方法

  }, //methods 结束


})

样式：

.container {
  border: 1px solid #eaeaea;
  padding: 7px 59px;
  margin-top: 10px;
}

.header {
  text-align: center;
  margin-top: 6px;
}

.close {
  position: relative;
  bottom: 227px;
  left: 171px;
}
.qrcode-box{
  margin-top: 4px;
}
.canvas {
  margin: 0 auto;
  position: relative;
  top: 9px;
}

.btn {
  position: relative;
  left: 41px;
  top:23px;
}

.save {
  color: #fff;
  background-color: #298ef7;
  border: 1px solid #eaeaea;
}

json:

{
  "component": true,
  "usingComponents": {
    "tui-button": "/static/thorui/components/button/button",
    "tui-icon": "/static/thorui/components/icon/icon"
  }
}

引入
引用组件必须加上这句。。！！！ this._htOption.usingIn
下面代码已有。

回调

weapp-qrcode.js

//Core code comes from https://github.com/davidshimjs/qrcodejs

var QRCode;

(function() {
  /**
   * Get the type by string length
   * 
   * @private
   * @param {String} sText
   * @param {Number} nCorrectLevel
   * @return {Number} type
   */
  function _getTypeNumber(sText, nCorrectLevel) {
    var nType = 1;
    var length = _getUTF8Length(sText);

    for (var i = 0, len = QRCodeLimitLength.length; i <= len; i++) {
      var nLimit = 0;

      switch (nCorrectLevel) {
        case QRErrorCorrectLevel.L:
          nLimit = QRCodeLimitLength[i][0];
          break;
        case QRErrorCorrectLevel.M:
          nLimit = QRCodeLimitLength[i][1];
          break;
        case QRErrorCorrectLevel.Q:
          nLimit = QRCodeLimitLength[i][2];
          break;
        case QRErrorCorrectLevel.H:
          nLimit = QRCodeLimitLength[i][3];
          break;
      }

      if (length <= nLimit) {
        break;
      } else {
        nType++;
      }
    }

    if (nType > QRCodeLimitLength.length) {
      throw new Error("Too long data");
    }

    return nType;
  }

  function _getUTF8Length(sText) {
    var replacedText = encodeURI(sText).toString().replace(/\%[0-9a-fA-F]{2}/g, 'a');
    return replacedText.length + (replacedText.length != sText ? 3 : 0);
  }

  function QR8bitByte(data) {
    this.mode = QRMode.MODE_8BIT_BYTE;
    this.data = data;
    this.parsedData = [];

    // Added to support UTF-8 Characters
    for (var i = 0, l = this.data.length; i < l; i++) {
      var byteArray = [];
      var code = this.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;
      }

      this.parsedData.push(byteArray);
    }

    this.parsedData = Array.prototype.concat.apply([], this.parsedData);

    if (this.parsedData.length != this.data.length) {
      this.parsedData.unshift(191);
      this.parsedData.unshift(187);
      this.parsedData.unshift(239);
    }
  }

  QR8bitByte.prototype = {
    getLength: function(buffer) {
      return this.parsedData.length;
    },
    write: function(buffer) {
      for (var i = 0, l = this.parsedData.length; i < l; i++) {
        buffer.put(this.parsedData[i], 8);
      }
    }
  };


  // QRCodeModel
  function QRCodeModel(typeNumber, errorCorrectLevel) {
    this.typeNumber = typeNumber;
    this.errorCorrectLevel = errorCorrectLevel;
    this.modules = null;
    this.moduleCount = 0;
    this.dataCache = null;
    this.dataList = [];
  }
  QRCodeModel.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() {
      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;
        }
      }
      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 = QRCodeModel.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);
      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;
        }
      }
      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;
        }
      }
      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;
          }
        }
      }
    }
  };
  QRCodeModel.PAD0 = 0xEC;
  QRCodeModel.PAD1 = 0x11;
  QRCodeModel.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);
    }
    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 +
        ")");
    }
    if (buffer.getLengthInBits() + 4 <= totalDataCount * 8) {
      buffer.put(0, 4);
    }
    while (buffer.getLengthInBits() % 8 != 0) {
      buffer.putBit(false);
    }
    while (true) {
      if (buffer.getLengthInBits() >= totalDataCount * 8) {
        break;
      }
      buffer.put(QRCodeModel.PAD0, 8);
      if (buffer.getLengthInBits() >= totalDataCount * 8) {
        break;
      }
      buffer.put(QRCodeModel.PAD1, 8);
    }
    return QRCodeModel.createBytes(buffer, rsBlocks);
  };
  QRCodeModel.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;
  };
  var QRMode = {
    MODE_NUMBER: 1 << 0,
    MODE_ALPHA_NUM: 1 << 1,
    MODE_8BIT_BYTE: 1 << 2,
    MODE_KANJI: 1 << 3
  };
  var QRErrorCorrectLevel = {
    L: 1,
    M: 0,
    Q: 3,
    H: 2
  };
  var QRMaskPattern = {
    PATTERN000: 0,
    PATTERN001: 1,
    PATTERN010: 2,
    PATTERN011: 3,
    PATTERN100: 4,
    PATTERN101: 5,
    PATTERN110: 6,
    PATTERN111: 7
  };
  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) {
        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) {
        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) {
        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;
      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);
          }
        }
      }
      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;
          }
        }
      }
      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;
          }
        }
      }
      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;
    }
  };
  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;
  }

  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);
      }
      return new QRPolynomial(num, 0).mod(e);
    }
  };

  function QRRSBlock(totalCount, dataCount) {
    this.totalCount = totalCount;
    this.dataCount = dataCount;
  }
  QRRSBlock.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]
  ];
  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 = [];
    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;
    }
  };

  function QRBitBuffer() {
    this.buffer = [];
    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++;
    }
  };
  var QRCodeLimitLength = [
    [17, 14, 11, 7],
    [32, 26, 20, 14],
    [53, 42, 32, 24],
    [78, 62, 46, 34],
    [106, 84, 60, 44],
    [134, 106, 74, 58],
    [154, 122, 86, 64],
    [192, 152, 108, 84],
    [230, 180, 130, 98],
    [271, 213, 151, 119],
    [321, 251, 177, 137],
    [367, 287, 203, 155],
    [425, 331, 241, 177],
    [458, 362, 258, 194],
    [520, 412, 292, 220],
    [586, 450, 322, 250],
    [644, 504, 364, 280],
    [718, 560, 394, 310],
    [792, 624, 442, 338],
    [858, 666, 482, 382],
    [929, 711, 509, 403],
    [1003, 779, 565, 439],
    [1091, 857, 611, 461],
    [1171, 911, 661, 511],
    [1273, 997, 715, 535],
    [1367, 1059, 751, 593],
    [1465, 1125, 805, 625],
    [1528, 1190, 868, 658],
    [1628, 1264, 908, 698],
    [1732, 1370, 982, 742],
    [1840, 1452, 1030, 790],
    [1952, 1538, 1112, 842],
    [2068, 1628, 1168, 898],
    [2188, 1722, 1228, 958],
    [2303, 1809, 1283, 983],
    [2431, 1911, 1351, 1051],
    [2563, 1989, 1423, 1093],
    [2699, 2099, 1499, 1139],
    [2809, 2213, 1579, 1219],
    [2953, 2331, 1663, 1273]
  ];

  // QRCode object
  QRCode = function(canvasId, vOption) {
    this._htOption = {
      width: 256,
      height: 256,
      typeNumber: 4,
      colorDark: "#000000",
      colorLight: "#ffffff",
      correctLevel: QRErrorCorrectLevel.H
    };

    if (typeof vOption === 'string') {
      vOption = {
        text: vOption
      };
    }

    // Overwrites options
    if (vOption) {
      for (var i in vOption) {
        this._htOption[i] = vOption[i];
      }
    }

    this._oQRCode = null;
    this.canvasId = canvasId

    if (this._htOption.text && this.canvasId) {
      this.makeCode(this._htOption.text);
    }
  };

  QRCode.prototype.makeCode = function(sText) {
    this._oQRCode = new QRCodeModel(_getTypeNumber(sText, this._htOption.correctLevel), this._htOption.correctLevel);
    this._oQRCode.addData(sText);
    this._oQRCode.make();
    this.makeImage();
  };

  QRCode.prototype.makeImage = function() {
    var _oContext
    if (this._htOption.usingIn) {
      _oContext = wx.createCanvasContext(this.canvasId, this._htOption.usingIn)
    } else {
      _oContext = wx.createCanvasContext(this.canvasId)
    }
    var _htOption = this._htOption;
    var oQRCode = this._oQRCode

    var nCount = oQRCode.getModuleCount();
    var nWidth = _htOption.width / nCount;
    var nHeight = _htOption.height / nCount;
    var nRoundedWidth = Math.round(nWidth);
    var nRoundedHeight = Math.round(nHeight);

    if (_htOption.image && _htOption.image != '') {
      _oContext.drawImage(_htOption.image, 0, 0, _htOption.width, _htOption.height)
    }

    for (var row = 0; row < nCount; row++) {
      for (var col = 0; col < nCount; col++) {
        var bIsDark = oQRCode.isDark(row, col);
        var nLeft = col * nWidth;
        var nTop = row * nHeight;
        _oContext.setStrokeStyle(bIsDark ? _htOption.colorDark : _htOption.colorLight)
        // _oContext.setStrokeStyle('yellow')
        _oContext.setLineWidth(1)
        _oContext.setFillStyle(bIsDark ? _htOption.colorDark : _htOption.colorLight)
        // _oContext.setFillStyle('red')
        // if (bIsDark) {
        _oContext.fillRect(nLeft, nTop, nWidth, nHeight);
        // }

        // 안티 앨리어싱 방지 처리
        // if (bIsDark) {
        _oContext.strokeRect(
          Math.floor(nLeft) + 0.5,
          Math.floor(nTop) + 0.5,
          nRoundedWidth,
          nRoundedHeight
        );

        _oContext.strokeRect(
          Math.ceil(nLeft) - 0.5,
          Math.ceil(nTop) - 0.5,
          nRoundedWidth,
          nRoundedHeight
        );
        // }
        // _oContext.fillRect(
        //     Math.floor(nLeft) + 0.5,
        //     Math.floor(nTop) + 0.5,
        //     nRoundedWidth,
        //     nRoundedHeight
        // );
        // _oContext.fillRect(
        //     Math.ceil(nLeft) - 0.5,
        //     Math.ceil(nTop) - 0.5,
        //     nRoundedWidth,
        //     nRoundedHeight
        // );
        // _oContext.clearRect(
        //     Math.floor(nLeft) + 0.5,
        //     Math.floor(nTop) + 0.5,
        //     nRoundedWidth,
        //     nRoundedHeight
        // );
        // _oContext.clearRect(
        //     Math.ceil(nLeft) - 0.5,
        //     Math.ceil(nTop) - 0.5,
        //     nRoundedWidth,
        //     nRoundedHeight
        // );
      }
    }

    _oContext.draw()
  };

  // 保存为图片，将临时路径传给回调
  QRCode.prototype.exportImage = function(callback) {
    if (!callback) {
      return
    }
    wx.canvasToTempFilePath({
      x: 0,
      y: 0,
      width: this._htOption.width,
      height: this._htOption.height,
      destWidth: this._htOption.width,
      destHeight: this._htOption.height,
      canvasId: this.canvasId,
      success: function(res) {
        // console.log(res.tempFilePath)
        // callback(res.tempFilePath)
        callback(res)
      },
      fail: function(res) {
        callback(res)
      }
    }, this._htOption.usingIn)
  }

  QRCode.CorrectLevel = QRErrorCorrectLevel;
})();

module.exports = QRCode