微信小程序之动态生成二维码并处理成本地图片

一.封装二维码生成器js

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//---------------------------------------------------------------------
//
// QR Code Generator for JavaScript
//
// Copyright (c) 2009 Kazuhiko Arase
//
// URL: [url=http://www.d-project.com/]http://www.d-project.com/[/url]
//
// Licensed under the MIT license:
//        [url=http://www.opensource.org/licenses/mit-license.php]http://www.opensource.org/licenses/mit-license.php[/url]
//
// The word 'QR Code' is registered trademark of
// DENSO WAVE INCORPORATED
//        [url=http://www.denso-wave.com/qrcode/faqpatent-e.html]http://www.denso-wave.com/qrcode/faqpatent-e.html[/url]
//
//---------------------------------------------------------------------
 
//---------------------------------------------------------------------
// qrcode
//代码第1588行为补充代码
//修改人：chenxing
//2017-02-27 16:21:32
//---------------------------------------------------------------------
 
/**
 * qrcode
 * @param typeNumber 1 to 40
 * @param errorCorrectLevel 'L','M','Q','H'
 */
var qrcode = function(typeNumber, errorCorrectLevel) {
 
    var PAD0 = 0xEC;
    var PAD1 = 0x11;
 
    var _typeNumber = typeNumber;
    var _errorCorrectLevel = QRErrorCorrectLevel[errorCorrectLevel];
    var _modules = null;
    var _moduleCount = 0;
    var _dataCache = null;
    var _dataList = new Array();
 
    var _this = {};
 
    var makeImpl = function(test, maskPattern) {
 
        _moduleCount = _typeNumber * 4 + 17;
        _modules = function(moduleCount) {
            var modules = new Array(moduleCount);
            for (var row = 0; row < moduleCount; row += 1) {
                modules[row] = new Array(moduleCount);
                for (var col = 0; col < moduleCount; col += 1) {
                    modules[row][col] = null;
                }
            }
            return modules;
        }(_moduleCount);
 
        setupPositionProbePattern(0, 0);
        setupPositionProbePattern(_moduleCount - 7, 0);
        setupPositionProbePattern(0, _moduleCount - 7);
        setupPositionAdjustPattern();
        setupTimingPattern();
        setupTypeInfo(test, maskPattern);
 
        if (_typeNumber >= 7) {
            setupTypeNumber(test);
        }
 
        if (_dataCache == null) {
            _dataCache = createData(_typeNumber, _errorCorrectLevel, _dataList);
        }
 
        mapData(_dataCache, maskPattern);
    };
 
    var setupPositionProbePattern = function(row, col) {
 
        for (var r = -1; r <= 7; r += 1) {
 
            if (row + r <= -1 || _moduleCount <= row + r) continue;
 
            for (var c = -1; c <= 7; c += 1) {
 
                if (col + c <= -1 || _moduleCount <= col + c) continue;
 
                if ( (0 <= r && r <= 6 && (c == 0 || c == 6) )
                     || (0 <= c && c <= 6 && (r == 0 || r == 6) )
                     || (2 <= r && r <= 4 && 2 <= c && c <= 4) ) {
                    _modules[row + r][col + c] = true;
                } else {
                    _modules[row + r][col + c] = false;
                }
            }
        }
    };
 
    var getBestMaskPattern = function() {
 
        var minLostPoint = 0;
        var pattern = 0;
 
        for (var i = 0; i < 8; i += 1) {
 
            makeImpl(true, i);
 
            var lostPoint = QRUtil.getLostPoint(_this);
 
            if (i == 0 || minLostPoint > lostPoint) {
                minLostPoint = lostPoint;
                pattern = i;
            }
        }
 
        return pattern;
    };
 
    var setupTimingPattern = function() {
 
        for (var r = 8; r < _moduleCount - 8; r += 1) {
            if (_modules[r][6] != null) {
                continue;
            }
            _modules[r][6] = (r % 2 == 0);
        }
 
        for (var c = 8; c < _moduleCount - 8; c += 1) {
            if (_modules[6][c] != null) {
                continue;
            }
            _modules[6][c] = (c % 2 == 0);
        }
    };
 
    var setupPositionAdjustPattern = function() {
 
        var pos = QRUtil.getPatternPosition(_typeNumber);
 
        for (var i = 0; i < pos.length; i += 1) {
 
            for (var j = 0; j < pos.length; j += 1) {
 
                var row = pos[i];
                var col = pos[j];
 
                if (_modules[row][col] != null) {
                    continue;
                }
 
                for (var r = -2; r <= 2; r += 1) {
 
                    for (var c = -2; c <= 2; c += 1) {
 
                        if (r == -2 || r == 2 || c == -2 || c == 2
                            || (r == 0 && c == 0) ) {
                            _modules[row + r][col + c] = true;
                        } else {
                            _modules[row + r][col + c] = false;
                        }
                    }
                }
            }
        }
    };
 
    var setupTypeNumber = function(test) {
 
        var bits = QRUtil.getBCHTypeNumber(_typeNumber);
 
        for (var i = 0; i < 18; i += 1) {
            var mod = (!test && ( (bits >> i) & 1) == 1);
            _modules[Math.floor(i / 3)][i % 3 + _moduleCount - 8 - 3] = mod;
        }
 
        for (var i = 0; i < 18; i += 1) {
            var mod = (!test && ( (bits >> i) & 1) == 1);
            _modules[i % 3 + _moduleCount - 8 - 3][Math.floor(i / 3)] = mod;
        }
    };
 
    var setupTypeInfo = function(test, maskPattern) {
 
        var data = (_errorCorrectLevel << 3) | maskPattern;
        var bits = QRUtil.getBCHTypeInfo(data);
 
        // vertical
        for (var i = 0; i < 15; i += 1) {
 
            var mod = (!test && ( (bits >> i) & 1) == 1);
 
            if (i < 6) {
                _modules[i][8] = mod;
            } else if (i < 8) {
                _modules[i + 1][8] = mod;
            } else {
                _modules[_moduleCount - 15 + i][8] = mod;
            }
        }
 
        // horizontal
        for (var i = 0; i < 15; i += 1) {
 
            var mod = (!test && ( (bits >> i) & 1) == 1);
 
            if (i < 8) {
                _modules[8][_moduleCount - i - 1] = mod;
            } else if (i < 9) {
                _modules[8][15 - i - 1 + 1] = mod;
            } else {
                _modules[8][15 - i - 1] = mod;
            }
        }
 
        // fixed module
        _modules[_moduleCount - 8][8] = (!test);
    };
 
    var mapData = function(data, maskPattern) {
 
        var inc = -1;
        var row = _moduleCount - 1;
        var bitIndex = 7;
        var byteIndex = 0;
        var maskFunc = QRUtil.getMaskFunction(maskPattern);
 
        for (var col = _moduleCount - 1; col > 0; col -= 2) {
 
            if (col == 6) col -= 1;
 
            while (true) {
 
                for (var c = 0; c < 2; c += 1) {
 
                    if (_modules[row][col - c] == null) {
 
                        var dark = false;
 
                        if (byteIndex < data.length) {
                            dark = ( ( (data[byteIndex] >>> bitIndex) & 1) == 1);
                        }
 
                        var mask = maskFunc(row, col - c);
 
                        if (mask) {
                            dark = !dark;
                        }
 
                        _modules[row][col - c] = dark;
                        bitIndex -= 1;
 
                        if (bitIndex == -1) {
                            byteIndex += 1;
                            bitIndex = 7;
                        }
                    }
                }
 
                row += inc;
 
                if (row < 0 || _moduleCount <= row) {
                    row -= inc;
                    inc = -inc;
                    break;
                }
            }
        }
    };
 
    var createBytes = function(buffer, rsBlocks) {
 
        var offset = 0;
 
        var maxDcCount = 0;
        var maxEcCount = 0;
 
        var dcdata = new Array(rsBlocks.length);
        var ecdata = new Array(rsBlocks.length);
 
        for (var r = 0; r < rsBlocks.length; r += 1) {
 
            var dcCount = rsBlocks[r].dataCount;
            var ecCount = rsBlocks[r].totalCount - dcCount;
 
            maxDcCount = Math.max(maxDcCount, dcCount);
            maxEcCount = Math.max(maxEcCount, ecCount);
 
            dcdata[r] = new Array(dcCount);
 
            for (var i = 0; i < dcdata[r].length; i += 1) {
                dcdata[r][i] = 0xff & buffer.getBuffer()[i + offset];
            }
            offset += dcCount;
 
            var rsPoly = QRUtil.getErrorCorrectPolynomial(ecCount);
            var rawPoly = qrPolynomial(dcdata[r], rsPoly.getLength() - 1);
 
            var modPoly = rawPoly.mod(rsPoly);
            ecdata[r] = new Array(rsPoly.getLength() - 1);
            for (var i = 0; i < ecdata[r].length; i += 1) {
                var modIndex = i + modPoly.getLength() - ecdata[r].length;
                ecdata[r][i] = (modIndex >= 0)? modPoly.getAt(modIndex) : 0;
            }
        }
 
        var totalCodeCount = 0;
        for (var i = 0; i < rsBlocks.length; i += 1) {
            totalCodeCount += rsBlocks[i].totalCount;
        }
 
        var data = new Array(totalCodeCount);
        var index = 0;
 
        for (var i = 0; i < maxDcCount; i += 1) {
            for (var r = 0; r < rsBlocks.length; r += 1) {
                if (i < dcdata[r].length) {
                    data[index] = dcdata[r][i];
                    index += 1;
                }
            }
        }
 
        for (var i = 0; i < maxEcCount; i += 1) {
            for (var r = 0; r < rsBlocks.length; r += 1) {
                if (i < ecdata[r].length) {
                    data[index] = ecdata[r][i];
                    index += 1;
                }
            }
        }
 
        return data;
    };
 
    var createData = function(typeNumber, errorCorrectLevel, dataList) {
 
        var rsBlocks = QRRSBlock.getRSBlocks(typeNumber, errorCorrectLevel);
 
        var buffer = qrBitBuffer();
 
        for (var i = 0; i < dataList.length; i += 1) {
            var data = dataList[i];
            buffer.put(data.getMode(), 4);
            buffer.put(data.getLength(), QRUtil.getLengthInBits(data.getMode(), typeNumber) );
            data.write(buffer);
        }
 
        // calc num max data.
        var totalDataCount = 0;
        for (var i = 0; i < rsBlocks.length; i += 1) {
            totalDataCount += rsBlocks[i].dataCount;
        }
 
        if (buffer.getLengthInBits() > totalDataCount * 8) {
            throw new Error('code length overflow. ('
                            + buffer.getLengthInBits()
                            + '>'
                            + totalDataCount * 8
                            + ')');
        }
 
        // end code
        if (buffer.getLengthInBits() + 4 <= totalDataCount * 8) {
            buffer.put(0, 4);
        }
 
        // padding
        while (buffer.getLengthInBits() % 8 != 0) {
            buffer.putBit(false);
        }
 
        // padding
        while (true) {
 
            if (buffer.getLengthInBits() >= totalDataCount * 8) {
                break;
            }
            buffer.put(PAD0, 8);
 
            if (buffer.getLengthInBits() >= totalDataCount * 8) {
                break;
            }
            buffer.put(PAD1, 8);
        }
 
        return createBytes(buffer, rsBlocks);
    };
 
    _this.addData = function(data) {
        var newData = qr8BitByte(data);
        _dataList.push(newData);
        _dataCache = null;
    };
 
    _this.isDark = function(row, col) {
        if (row < 0 || _moduleCount <= row || col < 0 || _moduleCount <= col) {
            throw new Error(row + ',' + col);
        }
        return _modules[row][col];
    };
 
    _this.getModuleCount = function() {
        return _moduleCount;
    };
 
    _this.make = function() {
        makeImpl(false, getBestMaskPattern() );
    };
 
    _this.createTableTag = function(cellSize, margin) {
 
        cellSize = cellSize || 2;
        margin = (typeof margin == 'undefined')? cellSize * 4 : margin;
 
        var qrHtml = '';
 
        qrHtml += '<table style="';
        qrHtml += ' border- 0px; border-style: none;';
        qrHtml += ' border-collapse: collapse;';
        qrHtml += ' padding: 0px; margin: ' + margin + 'px;';
        qrHtml += '">';
        qrHtml += '<tbody>';
 
        for (var r = 0; r < _this.getModuleCount(); r += 1) {
 
            qrHtml += '<tr>';
 
            for (var c = 0; c < _this.getModuleCount(); c += 1) {
                qrHtml += '<td style="';
                qrHtml += ' border- 0px; border-style: none;';
                qrHtml += ' border-collapse: collapse;';
                qrHtml += ' padding: 0px; margin: 0px;';
                qrHtml += '  ' + cellSize + 'px;';
                qrHtml += ' height: ' + cellSize + 'px;';
                qrHtml += ' background-color: ';
                qrHtml += _this.isDark(r, c)? '#000000' : '#ffffff';
                qrHtml += ';';
                qrHtml += '"/>';
            }
 
            qrHtml += '</tr>';
        }
 
        qrHtml += '</tbody>';
        qrHtml += '</table>';
 
        return qrHtml;
    };
 
    _this.createImgTag = function(cellSize, margin, size) {
 
        cellSize = cellSize || 2;
        margin = (typeof margin == 'undefined')? cellSize * 4 : margin;
 
        var min = margin;
        var max = _this.getModuleCount() * cellSize + margin;
 
        return createImgTag(size, size, function(x, y) {
            if (min <= x && x < max && min <= y && y < max) {
                var c = Math.floor( (x - min) / cellSize);
                var r = Math.floor( (y - min) / cellSize);
                return _this.isDark(r, c)? 0 : 1;
            } else {
                return 1;
            }
        } );
    };
 
    return _this;
};
 
//---------------------------------------------------------------------
// qrcode.stringToBytes
//---------------------------------------------------------------------
 
qrcode.stringToBytes = function(s) {
    var bytes = new Array();
    for (var i = 0; i < s.length; i += 1) {
        var c = s.charCodeAt(i);
        bytes.push(c & 0xff);
    }
    return bytes;
};
 
//---------------------------------------------------------------------
// qrcode.createStringToBytes
//---------------------------------------------------------------------
 
/**
 * @param unicodeData base64 string of byte array.
 * [16bit Unicode],[16bit Bytes], ...
 * @param numChars
 */
qrcode.createStringToBytes = function(unicodeData, numChars) {
 
    // create conversion map.
 
    var unicodeMap = function() {
 
        var bin = base64DecodeInputStream(unicodeData);
        var read = function() {
            var b = bin.read();
            if (b == -1) throw new Error();
            return b;
        };
 
        var count = 0;
        var unicodeMap = {};
        while (true) {
            var b0 = bin.read();
            if (b0 == -1) break;
            var b1 = read();
            var b2 = read();
            var b3 = read();
            var k = String.fromCharCode( (b0 << 8) | b1);
            var v = (b2 << 8) | b3;
            unicodeMap[k] = v;
            count += 1;
        }
        if (count != numChars) {
            throw new Error(count + ' != ' + numChars);
        }
 
        return unicodeMap;
    }();
 
    var unknownChar = '?'.charCodeAt(0);
 
    return function(s) {
        var bytes = new Array();
        for (var i = 0; i < s.length; i += 1) {
            var c = s.charCodeAt(i);
            if (c < 128) {
                bytes.push(c);
            } else {
                var b = unicodeMap[s.charAt(i)];
                if (typeof b == 'number') {
                    if ( (b & 0xff) == b) {
                        // 1byte
                        bytes.push(b);
                    } else {
                        // 2bytes
                        bytes.push(b >>> 8);
                        bytes.push(b & 0xff);
                    }
                } else {
                    bytes.push(unknownChar);
                }
            }
        }
        return bytes;
    };
};
 
//---------------------------------------------------------------------
// QRMode
//---------------------------------------------------------------------
 
var QRMode = {
    MODE_NUMBER :                1 << 0,
    MODE_ALPHA_NUM :         1 << 1,
    MODE_8BIT_BYTE :         1 << 2,
    MODE_KANJI :                1 << 3
};
 
//---------------------------------------------------------------------
// QRErrorCorrectLevel
//---------------------------------------------------------------------
 
var QRErrorCorrectLevel = {
    L : 1,
    M : 0,
    Q : 3,
    H : 2
};
 
//---------------------------------------------------------------------
// QRMaskPattern
//---------------------------------------------------------------------
 
var QRMaskPattern = {
    PATTERN000 : 0,
    PATTERN001 : 1,
    PATTERN010 : 2,
    PATTERN011 : 3,
    PATTERN100 : 4,
    PATTERN101 : 5,
    PATTERN110 : 6,
    PATTERN111 : 7
};
 
//---------------------------------------------------------------------
// QRUtil
//---------------------------------------------------------------------
 
var QRUtil = function() {
 
    var PATTERN_POSITION_TABLE = [
        [],
        [6, 18],
        [6, 22],
        [6, 26],
        [6, 30],
        [6, 34],
        [6, 22, 38],
        [6, 24, 42],
        [6, 26, 46],
        [6, 28, 50],
        [6, 30, 54],
        [6, 32, 58],
        [6, 34, 62],
        [6, 26, 46, 66],
        [6, 26, 48, 70],
        [6, 26, 50, 74],
        [6, 30, 54, 78],
        [6, 30, 56, 82],
        [6, 30, 58, 86],
        [6, 34, 62, 90],
        [6, 28, 50, 72, 94],
        [6, 26, 50, 74, 98],
        [6, 30, 54, 78, 102],
        [6, 28, 54, 80, 106],
        [6, 32, 58, 84, 110],
        [6, 30, 58, 86, 114],
        [6, 34, 62, 90, 118],
        [6, 26, 50, 74, 98, 122],
        [6, 30, 54, 78, 102, 126],
        [6, 26, 52, 78, 104, 130],
        [6, 30, 56, 82, 108, 134],
        [6, 34, 60, 86, 112, 138],
        [6, 30, 58, 86, 114, 142],
        [6, 34, 62, 90, 118, 146],
        [6, 30, 54, 78, 102, 126, 150],
        [6, 24, 50, 76, 102, 128, 154],
        [6, 28, 54, 80, 106, 132, 158],
        [6, 32, 58, 84, 110, 136, 162],
        [6, 26, 54, 82, 110, 138, 166],
        [6, 30, 58, 86, 114, 142, 170]
    ];
    var G15 = (1 << 10) | (1 << 8) | (1 << 5) | (1 << 4) | (1 << 2) | (1 << 1) | (1 << 0);
    var G18 = (1 << 12) | (1 << 11) | (1 << 10) | (1 << 9) | (1 << 8) | (1 << 5) | (1 << 2) | (1 << 0);
    var G15_MASK = (1 << 14) | (1 << 12) | (1 << 10) | (1 << 4) | (1 << 1);
 
    var _this = {};
 
    var getBCHDigit = function(data) {
        var digit = 0;
        while (data != 0) {
            digit += 1;
            data >>>= 1;
        }
        return digit;
    };
 
    _this.getBCHTypeInfo = function(data) {
        var d = data << 10;
        while (getBCHDigit(d) - getBCHDigit(G15) >= 0) {
            d ^= (G15 << (getBCHDigit(d) - getBCHDigit(G15) ) );
        }
        return ( (data << 10) | d) ^ G15_MASK;
    };
 
    _this.getBCHTypeNumber = function(data) {
        var d = data << 12;
        while (getBCHDigit(d) - getBCHDigit(G18) >= 0) {
            d ^= (G18 << (getBCHDigit(d) - getBCHDigit(G18) ) );
        }
        return (data << 12) | d;
    };
 
    _this.getPatternPosition = function(typeNumber) {
        return PATTERN_POSITION_TABLE[typeNumber - 1];
    };
 
    _this.getMaskFunction = function(maskPattern) {
 
        switch (maskPattern) {
 
            case QRMaskPattern.PATTERN000 :
                return function(i, j) { return (i + j) % 2 == 0; };
            case QRMaskPattern.PATTERN001 :
                return function(i, j) { return i % 2 == 0; };
            case QRMaskPattern.PATTERN010 :
                return function(i, j) { return j % 3 == 0; };
            case QRMaskPattern.PATTERN011 :
                return function(i, j) { return (i + j) % 3 == 0; };
            case QRMaskPattern.PATTERN100 :
                return function(i, j) { return (Math.floor(i / 2) + Math.floor(j / 3) ) % 2 == 0; };
            case QRMaskPattern.PATTERN101 :
                return function(i, j) { return (i * j) % 2 + (i * j) % 3 == 0; };
            case QRMaskPattern.PATTERN110 :
                return function(i, j) { return ( (i * j) % 2 + (i * j) % 3) % 2 == 0; };
            case QRMaskPattern.PATTERN111 :
                return function(i, j) { return ( (i * j) % 3 + (i + j) % 2) % 2 == 0; };
 
                default :
                throw new Error('bad maskPattern:' + maskPattern);
        }
    };
 
    _this.getErrorCorrectPolynomial = function(errorCorrectLength) {
        var a = qrPolynomial([1], 0);
        for (var i = 0; i < errorCorrectLength; i += 1) {
            a = a.multiply(qrPolynomial([1, QRMath.gexp(i)], 0) );
        }
        return a;
    };
 
    _this.getLengthInBits = function(mode, type) {
 
        if (1 <= type && type < 10) {
 
            // 1 - 9
 
            switch(mode) {
                case QRMode.MODE_NUMBER         : return 10;
                case QRMode.MODE_ALPHA_NUM         : return 9;
                case QRMode.MODE_8BIT_BYTE        : return 8;
                case QRMode.MODE_KANJI                : return 8;
                    default :
                    throw new Error('mode:' + mode);
            }
 
        } else if (type < 27) {
 
            // 10 - 26
 
            switch(mode) {
                case QRMode.MODE_NUMBER         : return 12;
                case QRMode.MODE_ALPHA_NUM         : return 11;
                case QRMode.MODE_8BIT_BYTE        : return 16;
                case QRMode.MODE_KANJI                : return 10;
                    default :
                    throw new Error('mode:' + mode);
            }
 
        } else if (type < 41) {
 
            // 27 - 40
 
            switch(mode) {
                case QRMode.MODE_NUMBER         : return 14;
                case QRMode.MODE_ALPHA_NUM        : return 13;
                case QRMode.MODE_8BIT_BYTE        : return 16;
                case QRMode.MODE_KANJI                : return 12;
                    default :
                    throw new Error('mode:' + mode);
            }
 
        } else {
            throw new Error('type:' + type);
        }
    };
 
    _this.getLostPoint = function(qrcode) {
 
        var moduleCount = qrcode.getModuleCount();
 
        var lostPoint = 0;
 
        // LEVEL1
 
        for (var row = 0; row < moduleCount; row += 1) {
            for (var col = 0; col < moduleCount; col += 1) {
 
                var sameCount = 0;
                var dark = qrcode.isDark(row, col);
 
                for (var r = -1; r <= 1; r += 1) {
 
                    if (row + r < 0 || moduleCount <= row + r) {
                        continue;
                    }
 
                    for (var c = -1; c <= 1; c += 1) {
 
                        if (col + c < 0 || moduleCount <= col + c) {
                            continue;
                        }
 
                        if (r == 0 && c == 0) {
                            continue;
                        }
 
                        if (dark == qrcode.isDark(row + r, col + c) ) {
                            sameCount += 1;
                        }
                    }
                }
 
                if (sameCount > 5) {
                    lostPoint += (3 + sameCount - 5);
                }
            }
        };
 
        // LEVEL2
 
        for (var row = 0; row < moduleCount - 1; row += 1) {
            for (var col = 0; col < moduleCount - 1; col += 1) {
                var count = 0;
                if (qrcode.isDark(row, col) ) count += 1;
                if (qrcode.isDark(row + 1, col) ) count += 1;
                if (qrcode.isDark(row, col + 1) ) count += 1;
                if (qrcode.isDark(row + 1, col + 1) ) count += 1;
                if (count == 0 || count == 4) {
                    lostPoint += 3;
                }
            }
        }
 
        // LEVEL3
 
        for (var row = 0; row < moduleCount; row += 1) {
            for (var col = 0; col < moduleCount - 6; col += 1) {
                if (qrcode.isDark(row, col)
                    && !qrcode.isDark(row, col + 1)
                    &&  qrcode.isDark(row, col + 2)
                    &&  qrcode.isDark(row, col + 3)
                    &&  qrcode.isDark(row, col + 4)
                    && !qrcode.isDark(row, col + 5)
                    &&  qrcode.isDark(row, col + 6) ) {
                    lostPoint += 40;
                }
            }
        }
 
        for (var col = 0; col < moduleCount; col += 1) {
            for (var row = 0; row < moduleCount - 6; row += 1) {
                if (qrcode.isDark(row, col)
                    && !qrcode.isDark(row + 1, col)
                    &&  qrcode.isDark(row + 2, col)
                    &&  qrcode.isDark(row + 3, col)
                    &&  qrcode.isDark(row + 4, col)
                    && !qrcode.isDark(row + 5, col)
                    &&  qrcode.isDark(row + 6, col) ) {
                    lostPoint += 40;
                }
            }
        }
 
        // LEVEL4
 
        var darkCount = 0;
 
        for (var col = 0; col < moduleCount; col += 1) {
            for (var row = 0; row < moduleCount; row += 1) {
                if (qrcode.isDark(row, col) ) {
                    darkCount += 1;
                }
            }
        }
 
        var ratio = Math.abs(100 * darkCount / moduleCount / moduleCount - 50) / 5;
        lostPoint += ratio * 10;
 
        return lostPoint;
    };
 
    return _this;
}();
 
//---------------------------------------------------------------------
// QRMath
//---------------------------------------------------------------------
 
var QRMath = function() {
 
    var EXP_TABLE = new Array(256);
    var LOG_TABLE = new Array(256);
 
    // initialize tables
    for (var i = 0; i < 8; i += 1) {
        EXP_TABLE[i] = 1 << i;
    }
    for (var i = 8; i < 256; i += 1) {
        EXP_TABLE[i] = EXP_TABLE[i - 4]
            ^ EXP_TABLE[i - 5]
            ^ EXP_TABLE[i - 6]
            ^ EXP_TABLE[i - 8];
    }
    for (var i = 0; i < 255; i += 1) {
        LOG_TABLE[EXP_TABLE[i] ] = i;
    }
 
    var _this = {};
 
    _this.glog = function(n) {
 
        if (n < 1) {
            throw new Error('glog(' + n + ')');
        }
 
        return LOG_TABLE[n];
    };
 
    _this.gexp = function(n) {
 
        while (n < 0) {
            n += 255;
        }
 
        while (n >= 256) {
            n -= 255;
        }
 
        return EXP_TABLE[n];
    };
 
    return _this;
}();
 
//---------------------------------------------------------------------
// qrPolynomial
//---------------------------------------------------------------------
 
function qrPolynomial(num, shift) {
 
    if (typeof num.length == 'undefined') {
        throw new Error(num.length + '/' + shift);
    }
 
    var _num = function() {
        var offset = 0;
        while (offset < num.length && num[offset] == 0) {
            offset += 1;
        }
        var _num = new Array(num.length - offset + shift);
        for (var i = 0; i < num.length - offset; i += 1) {
            _num[i] = num[i + offset];
        }
        return _num;
    }();
 
    var _this = {};
 
    _this.getAt = function(index) {
        return _num[index];
    };
 
    _this.getLength = function() {
        return _num.length;
    };
 
    _this.multiply = function(e) {
 
        var num = new Array(_this.getLength() + e.getLength() - 1);
 
        for (var i = 0; i < _this.getLength(); i += 1) {
            for (var j = 0; j < e.getLength(); j += 1) {
                num[i + j] ^= QRMath.gexp(QRMath.glog(_this.getAt(i) ) + QRMath.glog(e.getAt(j) ) );
            }
        }
 
        return qrPolynomial(num, 0);
    };
 
    _this.mod = function(e) {
 
        if (_this.getLength() - e.getLength() < 0) {
            return _this;
        }
 
        var ratio = QRMath.glog(_this.getAt(0) ) - QRMath.glog(e.getAt(0) );
 
        var num = new Array(_this.getLength() );
        for (var i = 0; i < _this.getLength(); i += 1) {
            num[i] = _this.getAt(i);
        }
 
        for (var i = 0; i < e.getLength(); i += 1) {
            num[i] ^= QRMath.gexp(QRMath.glog(e.getAt(i) ) + ratio);
        }
 
        // recursive call
        return qrPolynomial(num, 0).mod(e);
    };
 
    return _this;
};
 
//---------------------------------------------------------------------
// QRRSBlock
//---------------------------------------------------------------------
 
var QRRSBlock = function() {
 
 
    // [1: [L, M, Q, H], ..]
    var RS_BLOCK_TABLE=[[1,26,19],[1,26,16],[1,26,13],[1,26,9],[1,44,34],[1,44,28],[1,44,22],[1,44,16],[1,70,55],[1,70,44],[2,35,17],[2,35,13],[1,100,80],[2,50,32],[2,50,24],[4,25,9],[1,134,108],[2,67,43],[2,33,15,2,34,16],[2,33,11,2,34,12],[2,86,68],[4,43,27],[4,43,19],[4,43,15],[2,98,78],[4,49,31],[2,32,14,4,33,15],[4,39,13,1,40,14],[2,121,97],[2,60,38,2,61,39],[4,40,18,2,41,19],[4,40,14,2,41,15],[2,146,116],[3,58,36,2,59,37],[4,36,16,4,37,17],[4,36,12,4,37,13],[2,86,68,2,87,69],[4,69,43,1,70,44],[6,43,19,2,44,20],[6,43,15,2,44,16],[4,101,81],[1,80,50,4,81,51],[4,50,22,4,51,23],[3,36,12,8,37,13],[2,116,92,2,117,93],[6,58,36,2,59,37],[4,46,20,6,47,21],[7,42,14,4,43,15],[4,133,107],[8,59,37,1,60,38],[8,44,20,4,45,21],[12,33,11,4,34,12],[3,145,115,1,146,116],[4,64,40,5,65,41],[11,36,16,5,37,17],[11,36,12,5,37,13],[5,109,87,1,110,88],[5,65,41,5,66,42],[5,54,24,7,55,25],[11,36,12],[5,122,98,1,123,99],[7,73,45,3,74,46],[15,43,19,2,44,20],[3,45,15,13,46,16],[1,135,107,5,136,108],[10,74,46,1,75,47],[1,50,22,15,51,23],[2,42,14,17,43,15],[5,150,120,1,151,121],[9,69,43,4,70,44],[17,50,22,1,51,23],[2,42,14,19,43,15],[3,141,113,4,142,114],[3,70,44,11,71,45],[17,47,21,4,48,22],[9,39,13,16,40,14],[3,135,107,5,136,108],[3,67,41,13,68,42],[15,54,24,5,55,25],[15,43,15,10,44,16],[4,144,116,4,145,117],[17,68,42],[17,50,22,6,51,23],[19,46,16,6,47,17],[2,139,111,7,140,112],[17,74,46],[7,54,24,16,55,25],[34,37,13],[4,151,121,5,152,122],[4,75,47,14,76,48],[11,54,24,14,55,25],[16,45,15,14,46,16],[6,147,117,4,148,118],[6,73,45,14,74,46],[11,54,24,16,55,25],[30,46,16,2,47,17],[8,132,106,4,133,107],[8,75,47,13,76,48],[7,54,24,22,55,25],[22,45,15,13,46,16],[10,142,114,2,143,115],[19,74,46,4,75,47],[28,50,22,6,51,23],[33,46,16,4,47,17],[8,152,122,4,153,123],[22,73,45,3,74,46],[8,53,23,26,54,24],[12,45,15,28,46,16],[3,147,117,10,148,118],[3,73,45,23,74,46],[4,54,24,31,55,25],[11,45,15,31,46,16],[7,146,116,7,147,117],[21,73,45,7,74,46],[1,53,23,37,54,24],[19,45,15,26,46,16],[5,145,115,10,146,116],[19,75,47,10,76,48],[15,54,24,25,55,25],[23,45,15,25,46,16],[13,145,115,3,146,116],[2,74,46,29,75,47],[42,54,24,1,55,25],[23,45,15,28,46,16],[17,145,115],[10,74,46,23,75,47],[10,54,24,35,55,25],[19,45,15,35,46,16],[17,145,115,1,146,116],[14,74,46,21,75,47],[29,54,24,19,55,25],[11,45,15,46,46,16],[13,145,115,6,146,116],[14,74,46,23,75,47],[44,54,24,7,55,25],[59,46,16,1,47,17],[12,151,121,7,152,122],[12,75,47,26,76,48],[39,54,24,14,55,25],[22,45,15,41,46,16],[6,151,121,14,152,122],[6,75,47,34,76,48],[46,54,24,10,55,25],[2,45,15,64,46,16],[17,152,122,4,153,123],[29,74,46,14,75,47],[49,54,24,10,55,25],[24,45,15,46,46,16],[4,152,122,18,153,123],[13,74,46,32,75,47],[48,54,24,14,55,25],[42,45,15,32,46,16],[20,147,117,4,148,118],[40,75,47,7,76,48],[43,54,24,22,55,25],[10,45,15,67,46,16],[19,148,118,6,149,119],[18,75,47,31,76,48],[34,54,24,34,55,25],[20,45,15,61,46,16]];
 
    var qrRSBlock = function(totalCount, dataCount) {
        var _this = {};
        _this.totalCount = totalCount;
        _this.dataCount = dataCount;
        return _this;
    };
 
    var _this = {};
 
    var getRsBlockTable = function(typeNumber, errorCorrectLevel) {
 
        switch(errorCorrectLevel) {
            case QRErrorCorrectLevel.L :
                return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 0];
            case QRErrorCorrectLevel.M :
                return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 1];
            case QRErrorCorrectLevel.Q :
                return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 2];
            case QRErrorCorrectLevel.H :
                return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 3];
                default :
                return undefined;
        }
    };
 
    _this.getRSBlocks = function(typeNumber, errorCorrectLevel) {
 
        var rsBlock = getRsBlockTable(typeNumber, errorCorrectLevel);
 
        if (typeof rsBlock == 'undefined') {
            throw new Error('bad rs block [url=home.php?mod=space&uid=5302]@[/url] typeNumber:' + typeNumber +
                            '/errorCorrectLevel:' + errorCorrectLevel);
        }
 
        var length = rsBlock.length / 3;
 
        var list = new Array();
 
        for (var i = 0; i < length; i += 1) {
 
            var count = rsBlock[i * 3 + 0];
            var totalCount = rsBlock[i * 3 + 1];
            var dataCount = rsBlock[i * 3 + 2];
 
            for (var j = 0; j < count; j += 1) {
                list.push(qrRSBlock(totalCount, dataCount) );
            }
        }
 
        return list;
    };
 
    return _this;
}();
 
//---------------------------------------------------------------------
// qrBitBuffer
//---------------------------------------------------------------------
 
var qrBitBuffer = function() {
 
    var _buffer = new Array();
    var _length = 0;
 
    var _this = {};
 
    _this.getBuffer = function() {
        return _buffer;
    };
 
    _this.getAt = function(index) {
        var bufIndex = Math.floor(index / 8);
        return ( (_buffer[bufIndex] >>> (7 - index % 8) ) & 1) == 1;
    };
 
    _this.put = function(num, length) {
        for (var i = 0; i < length; i += 1) {
            _this.putBit( ( (num >>> (length - i - 1) ) & 1) == 1);
        }
    };
 
    _this.getLengthInBits = function() {
        return _length;
    };
 
    _this.putBit = function(bit) {
 
        var bufIndex = Math.floor(_length / 8);
        if (_buffer.length <= bufIndex) {
            _buffer.push(0);
        }
 
        if (bit) {
            _buffer[bufIndex] |= (0x80 >>> (_length % 8) );
        }
 
        _length += 1;
    };
 
    return _this;
};
 
//---------------------------------------------------------------------
// qr8BitByte
//---------------------------------------------------------------------
 
var qr8BitByte = function(data) {
 
    var _mode = QRMode.MODE_8BIT_BYTE;
    var _data = data;
    var _parsedData = [];
 
    var _this = {};
 
 
    // Added to support UTF-8 Characters
    for (var i = 0, l = _data.length; i < l; i++) {
        var byteArray = [];
        var code = _data.charCodeAt(i);
 
        if (code > 0x10000) {
            byteArray[0] = 0xF0 | ((code & 0x1C0000) >>> 18);
            byteArray[1] = 0x80 | ((code & 0x3F000) >>> 12);
            byteArray[2] = 0x80 | ((code & 0xFC0) >>> 6);
            byteArray[3] = 0x80 | (code & 0x3F);
        } else if (code > 0x800) {
            byteArray[0] = 0xE0 | ((code & 0xF000) >>> 12);
            byteArray[1] = 0x80 | ((code & 0xFC0) >>> 6);
            byteArray[2] = 0x80 | (code & 0x3F);
        } else if (code > 0x80) {
            byteArray[0] = 0xC0 | ((code & 0x7C0) >>> 6);
            byteArray[1] = 0x80 | (code & 0x3F);
        } else {
            byteArray[0] = code;
        }
 
        // Fix Unicode corruption bug
        _parsedData.push(byteArray);
    }
 
    _parsedData = Array.prototype.concat.apply([], _parsedData);
 
    if (_parsedData.length != _data.length) {
        _parsedData.unshift(191);
        _parsedData.unshift(187);
        _parsedData.unshift(239);
    }
 
    var _bytes = _parsedData;
 
    _this.getMode = function() {
        return _mode;
    };
 
    _this.getLength = function(buffer) {
        return _bytes.length;
    };
 
    _this.write = function(buffer) {
        for (var i = 0; i < _bytes.length; i += 1) {
            buffer.put(_bytes[i], 8);
        }
    };
 
    return _this;
};
 
//=====================================================================
// GIF Support etc.
//
 
//---------------------------------------------------------------------
// byteArrayOutputStream
//---------------------------------------------------------------------
 
var byteArrayOutputStream = function() {
 
    var _bytes = new Array();
 
    var _this = {};
 
    _this.writeByte = function(b) {
        _bytes.push(b & 0xff);
    };
 
    _this.writeShort = function(i) {
        _this.writeByte(i);
        _this.writeByte(i >>> 8);
    };
 
    _this.writeBytes = function(b, off, len) {
        off = off || 0;
        len = len || b.length;
        for (var i = 0; i < len; i += 1) {
            _this.writeByte(b[i + off]);
        }
    };
 
    _this.writeString = function(s) {
        for (var i = 0; i < s.length; i += 1) {
            _this.writeByte(s.charCodeAt(i) );
        }
    };
 
    _this.toByteArray = function() {
        return _bytes;
    };
 
    _this.toString = function() {
        var s = '';
        s += '[';
        for (var i = 0; i < _bytes.length; i += 1) {
            if (i > 0) {
                s += ',';
            }
            s += _bytes[i];
        }
        s += ']';
        return s;
    };
 
    return _this;
};
 
//---------------------------------------------------------------------
// base64EncodeOutputStream
//---------------------------------------------------------------------
 
var base64EncodeOutputStream = function() {
 
    var _buffer = 0;
    var _buflen = 0;
    var _length = 0;
    var _base64 = '';
 
    var _this = {};
 
    var writeEncoded = function(b) {
        _base64 += String.fromCharCode(encode(b & 0x3f) );
    };
 
    var encode = function(n) {
        if (n < 0) {
            // error.
        } else if (n < 26) {
            return 0x41 + n;
        } else if (n < 52) {
            return 0x61 + (n - 26);
        } else if (n < 62) {
            return 0x30 + (n - 52);
        } else if (n == 62) {
            return 0x2b;
        } else if (n == 63) {
            return 0x2f;
        }
        throw new Error('n:' + n);
    };
 
    _this.writeByte = function(n) {
 
        _buffer = (_buffer << 8) | (n & 0xff);
        _buflen += 8;
        _length += 1;
 
        while (_buflen >= 6) {
            writeEncoded(_buffer >>> (_buflen - 6) );
            _buflen -= 6;
        }
    };
 
    _this.flush = function() {
 
        if (_buflen > 0) {
            writeEncoded(_buffer << (6 - _buflen) );
            _buffer = 0;
            _buflen = 0;
        }
 
        if (_length % 3 != 0) {
            // padding
            var padlen = 3 - _length % 3;
            for (var i = 0; i < padlen; i += 1) {
                _base64 += '=';
            }
        }
    };
 
    _this.toString = function() {
        return _base64;
    };
 
    return _this;
};
 
//---------------------------------------------------------------------
// base64DecodeInputStream
//---------------------------------------------------------------------
 
var base64DecodeInputStream = function(str) {
 
    var _str = str;
    var _pos = 0;
    var _buffer = 0;
    var _buflen = 0;
 
    var _this = {};
 
    _this.read = function() {
 
        while (_buflen < 8) {
 
            if (_pos >= _str.length) {
                if (_buflen == 0) {
                    return -1;
                }
                throw new Error('unexpected end of file./' + _buflen);
            }
 
            var c = _str.charAt(_pos);
            _pos += 1;
 
            if (c == '=') {
                _buflen = 0;
                return -1;
            } else if (c.match(/^s$/) ) {
                // ignore if whitespace.
                continue;
            }
 
            _buffer = (_buffer << 6) | decode(c.charCodeAt(0) );
            _buflen += 6;
        }
 
        var n = (_buffer >>> (_buflen - 8) ) & 0xff;
        _buflen -= 8;
        return n;
    };
 
    var decode = function(c) {
        if (0x41 <= c && c <= 0x5a) {
            return c - 0x41;
        } else if (0x61 <= c && c <= 0x7a) {
            return c - 0x61 + 26;
        } else if (0x30 <= c && c <= 0x39) {
            return c - 0x30 + 52;
        } else if (c == 0x2b) {
            return 62;
        } else if (c == 0x2f) {
            return 63;
        } else {
            throw new Error('c:' + c);
        }
    };
 
    return _this;
};
 
//---------------------------------------------------------------------
// gifImage (B/W)
//---------------------------------------------------------------------
 
var gifImage = function(width, height) {
 
    var _width = width;
    var _height = height;
    var _data = new Array(width * height);
 
    var _this = {};
 
    _this.setPixel = function(x, y, pixel) {
        _data[y * _width + x] = pixel;
    };
 
    _this.write = function(out) {
 
        //---------------------------------
        // GIF Signature
 
        out.writeString('GIF87a');
 
        //---------------------------------
        // Screen Descriptor
 
        out.writeShort(_width);
        out.writeShort(_height);
 
        out.writeByte(0x80); // 2bit
        out.writeByte(0);
        out.writeByte(0);
 
        //---------------------------------
        // Global Color Map
 
        // black
        out.writeByte(0x00);
        out.writeByte(0x00);
        out.writeByte(0x00);
 
        // white
        out.writeByte(0xff);
        out.writeByte(0xff);
        out.writeByte(0xff);
 
        //---------------------------------
        // Image Descriptor
 
        out.writeString(',');
        out.writeShort(0);
        out.writeShort(0);
        out.writeShort(_width);
        out.writeShort(_height);
        out.writeByte(0);
 
        //---------------------------------
        // Local Color Map
 
        //---------------------------------
        // Raster Data
 
        var lzwMinCodeSize = 2;
        var raster = getLZWRaster(lzwMinCodeSize);
 
        out.writeByte(lzwMinCodeSize);
 
        var offset = 0;
 
        while (raster.length - offset > 255) {
            out.writeByte(255);
            out.writeBytes(raster, offset, 255);
            offset += 255;
        }
 
        out.writeByte(raster.length - offset);
        out.writeBytes(raster, offset, raster.length - offset);
        out.writeByte(0x00);
 
        //---------------------------------
        // GIF Terminator
        out.writeString(';');
    };
 
    var bitOutputStream = function(out) {
 
        var _out = out;
        var _bitLength = 0;
        var _bitBuffer = 0;
 
        var _this = {};
 
        _this.write = function(data, length) {
 
            if ( (data >>> length) != 0) {
                throw new Error('length over');
            }
 
            while (_bitLength + length >= 8) {
                _out.writeByte(0xff & ( (data << _bitLength) | _bitBuffer) );
                length -= (8 - _bitLength);
                data >>>= (8 - _bitLength);
                _bitBuffer = 0;
                _bitLength = 0;
            }
 
            _bitBuffer = (data << _bitLength) | _bitBuffer;
            _bitLength = _bitLength + length;
        };
 
        _this.flush = function() {
            if (_bitLength > 0) {
                _out.writeByte(_bitBuffer);
            }
        };
 
        return _this;
    };
 
    var getLZWRaster = function(lzwMinCodeSize) {
 
        var clearCode = 1 << lzwMinCodeSize;
        var endCode = (1 << lzwMinCodeSize) + 1;
        var bitLength = lzwMinCodeSize + 1;
 
        // Setup LZWTable
        var table = lzwTable();
 
        for (var i = 0; i < clearCode; i += 1) {
            table.add(String.fromCharCode(i) );
        }
        table.add(String.fromCharCode(clearCode) );
        table.add(String.fromCharCode(endCode) );
 
        var byteOut = byteArrayOutputStream();
        var bitOut = bitOutputStream(byteOut);
 
        // clear code
        bitOut.write(clearCode, bitLength);
 
        var dataIndex = 0;
 
        var s = String.fromCharCode(_data[dataIndex]);
        dataIndex += 1;
 
        while (dataIndex < _data.length) {
 
            var c = String.fromCharCode(_data[dataIndex]);
            dataIndex += 1;
 
            if (table.contains(s + c) ) {
 
                s = s + c;
 
            } else {
 
                bitOut.write(table.indexOf(s), bitLength);
 
                if (table.size() < 0xfff) {
 
                    if (table.size() == (1 << bitLength) ) {
                        bitLength += 1;
                    }
 
                    table.add(s + c);
                }
 
                s = c;
            }
        }
 
        bitOut.write(table.indexOf(s), bitLength);
 
        // end code
        bitOut.write(endCode, bitLength);
 
        bitOut.flush();
 
        return byteOut.toByteArray();
    };
 
    var lzwTable = function() {
 
        var _map = {};
        var _size = 0;
 
        var _this = {};
 
        _this.add = function(key) {
            if (_this.contains(key) ) {
                throw new Error('dup key:' + key);
            }
            _map[key] = _size;
            _size += 1;
        };
 
        _this.size = function() {
            return _size;
        };
 
        _this.indexOf = function(key) {
            return _map[key];
        };
 
        _this.contains = function(key) {
            return typeof _map[key] != 'undefined';
        };
 
        return _this;
    };
 
    return _this;
};
 
var createImgTag = function(width, height, getPixel, alt) {
 
    var gif = gifImage(width, height);
    for (var y = 0; y < height; y += 1) {
        for (var x = 0; x < width; x += 1) {
            gif.setPixel(x, y, getPixel(x, y) );
        }
    }
 
    var b = byteArrayOutputStream();
    gif.write(b);
 
    var base64 = base64EncodeOutputStream();
    var bytes = b.toByteArray();
    for (var i = 0; i < bytes.length; i += 1) {
        base64.writeByte(bytes[i]);
    }
    base64.flush();
 
    var img = '';
    img += 'data:image/gif;base64,';
    img += base64;
 
    return img;
};
 
//---------------------------------------------------------------------
// returns qrcode function.
 
var createQrCodeImg = function(text, options) {
    options = options || {};
    var typeNumber = options.typeNumber || 4;
    var errorCorrectLevel = options.errorCorrectLevel || 'M';
    var size = options.size || 500;
 
    var qr;
 
    try {
        qr = qrcode(typeNumber, errorCorrectLevel || 'M');
        qr.addData(text);
        qr.make();
    } catch (e) {
        if(typeNumber >= 40) {
            throw new Error('Text too long to encode');
        } else {
            return gen(text, {
                size: size,
                errorCorrectLevel: errorCorrectLevel,
                typeNumber: typeNumber + 1
            });
        }
    }
 
    // calc cellsize and margin
    var cellsize = parseInt(size / qr.getModuleCount());
    var margin = parseInt((size - qr.getModuleCount() * cellsize) / 2);
 
    return qr.createImgTag(cellsize, margin, size);
};
// var module = {}; 需要注释这一行，否则微信小程序无法使用
module.exports = {
        createQrCodeImg : createQrCodeImg
};

封装base64转为本地图片js

// 小程序分享二维码是base64格式，在制作分享图时，需要转换为图片格式
const fsm = wx.getFileSystemManager();
const FILE_BASE_NAME = 'tmp_base64src'; //自定义文件名

function base64src(base64data, cb) {
  const [, format, bodyData] = /data:image/(w+);base64,(.*)/.exec(base64data) || [];
  if (!format) {
    return (new Error('ERROR_BASE64SRC_PARSE'));
  }
  const filePath = `${wx.env.USER_DATA_PATH}/${FILE_BASE_NAME}.${format}`;
  const buffer = wx.base64ToArrayBuffer(bodyData);
  fsm.writeFile({
    filePath,
    data: buffer,
    encoding: 'binary',
    success() {
      cb(filePath);
    },
    fail() {
      return (new Error('ERROR_BASE64SRC_WRITE'));
    },
  });
};
export { base64src };

在页面引入封装好的js

onload

绘制二维码转成本地图片

 createQRCode: function(text, size) {
    //调用插件中的draw方法，绘制二维码图片

    let that = this

    // console.log('QRcode: ', text, size)
    let _img = QR.createQrCodeImg(text, {
      size: parseInt(size)
    })
    // let qucode = that.data.qucode;
    // qucode=_img
    that.setData({
      'qrcode': _img
    })
    console.log('商品二维码----->', that.data.qrcode,that.data.qrcode.length)    
    
    // 处理二维码成本地图片
   
    base64src(that.data.qrcode, res => {
      console.log(res) // 返回图片地址，直接赋值到image标签即可
      that.setData({
        'qrcode': res
      })
    });
   
  },