微信小程序实用Demo: 小程序内生成image格式qrcode（二维码）
wxqrcode.js 不依赖任何类库，可以生成二维码图片base64编码（data:image/gif;base64,xxx…）
可以用于小程序页内生成二维码。文章后有代码下地址。
小程序页面wxml代码：
<!--pages/wxqrcode/demo1.wxml-->
<view class='container'>
<hr/>
<view style='font-size:24rpx; text-align: center; '>Demo for create QR code Image with wxqrcode.js </view>
<hr/>
<textarea bindinput='bind_text' value='{{text}}' style='background:#f4f4f4;margin:30rpx auto; padding:20rpx; width:650rpx;' />
<hr/>
<button bindtap='bind_sumbit'>提交</button>
<hr/>
<image src="{{qrcode}}" class="qrcode"></image>
</view>
小程序页面wxss代码：
/* pages/wxqrcode/demo1.wxss */
page{
height:100%
}
text {
text-align: center;
}
.qrcode {
width: 278rpx;
height: 278rpx;
display: block;
margin: 0 auto;
}
hr{ clear: both; height: 0; display: block; border-top:1rpx solid #eee; margin: 20rpx 0;}
小程序页面js代码：
// pages/wxqrcode/demo1.js
const QR = require('./wxqrcode.js');
Page({
data: {
// qrcode
text: 'http://www.lrxin.com',
qrcode: ''
},
onLoad: function (options) {
var that = this;
let qrcodeSize = that.getQRCodeSize()
that.createQRCode(that.data.text, qrcodeSize)
},
//适配不同屏幕大小的canvas
getQRCodeSize: function () {
var size = 0;
try {
var res = wx.getSystemInfoSync();
var scale = res.windowWidth / 750; //不同屏幕下QRcode的适配比例；设计稿是750宽
var width = 300 * scale;
size = width;
} catch (e) {
// Do something when catch error
console.log("获取设备信息失败" + e);
size = 150;
}
return size;
},
createQRCode: function (text, size) {
//调用插件中的draw方法，绘制二维码图片
let that = this
try {
// console.log('QRcode: ', text, size)
let _img = QR.createQrCodeImg(text, {
size: parseInt(size)
})
that.setData({
'qrcode': _img
})
} catch (e) {
console.log(e)
}
},
bind_text(e) {
let text = e.detail.value;
this.setData({
text: text
});
},
bind_sumbit(e) {
this.onLoad();
}
});
小程序js代码 引用生成二维码js文件 wxqrcode.js ：
//---------------------------------------------------------------------
//
// 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-width: 0px; border-style: none;';
qrHtml += ' border-collapse: collapse;';
qrHtml += ' padding: 0px; margin: ' + margin + 'px;';
qrHtml += '">';
qrHtml += '<tbody>';
for (var r = 0; r < _this.getModuleCount(); r += 1) {
qrHtml += '<tr>';
for (var c = 0; c < _this.getModuleCount(); c += 1) {
qrHtml += '<td style="';
qrHtml += ' border-width: 0px; border-style: none;';
qrHtml += ' border-collapse: collapse;';
qrHtml += ' padding: 0px; margin: 0px;';
qrHtml += ' width: ' + cellSize + 'px;';
qrHtml += ' height: ' + cellSize + 'px;';
qrHtml += ' background-color: ';
qrHtml += _this.isDark(r, c)? '#000000' : '#ffffff';
qrHtml += ';';
qrHtml += '"/>';
}
qrHtml += '</tr>';
}
qrHtml += '</tbody>';
qrHtml += '</table>';
return qrHtml;
};
_this.createImgTag = function(cellSize, margin, size) {
cellSize = cellSize || 2;
margin = (typeof margin == 'undefined')? cellSize * 4 : margin;
var min = margin;
var max = _this.getModuleCount() * cellSize + margin;
return createImgTag(size, size, function(x, y) {
if (min <= x && x < max && min <= y && y < max) {
var c = Math.floor( (x - min) / cellSize);
var r = Math.floor( (y - min) / cellSize);
return _this.isDark(r, c)? 0 : 1;
} else {
return 1;
}
} );
};
return _this;
};
//---------------------------------------------------------------------
// qrcode.stringToBytes
//---------------------------------------------------------------------
qrcode.stringToBytes = function(s) {
var bytes = new Array();
for (var i = 0; i < s.length; i += 1) {
var c = s.charCodeAt(i);
bytes.push(c & 0xff);
}
return bytes;
};
//---------------------------------------------------------------------
// qrcode.createStringToBytes
//---------------------------------------------------------------------
/**
* @param unicodeData base64 string of byte array.
* [16bit Unicode],[16bit Bytes], ...
* @param numChars
*/
qrcode.createStringToBytes = function(unicodeData, numChars) {
// create conversion map.
var unicodeMap = function() {
var bin = base64DecodeInputStream(unicodeData);
var read = function() {
var b = bin.read();
if (b == -1) throw new Error();
return b;
};
var count = 0;
var unicodeMap = {};
while (true) {
var b0 = bin.read();
if (b0 == -1) break;
var b1 = read();
var b2 = read();
var b3 = read();
var k = String.fromCharCode( (b0 << 8) | b1);
var v = (b2 << 8) | b3;
unicodeMap[k] = v;
count += 1;
}
if (count != numChars) {
throw new Error(count + ' != ' + numChars);
}
return unicodeMap;
}();
var unknownChar = '?'.charCodeAt(0);
return function(s) {
var bytes = new Array();
for (var i = 0; i < s.length; i += 1) {
var c = s.charCodeAt(i);
if (c < 128) {
bytes.push(c);
} else {
var b = unicodeMap[s.charAt(i)];
if (typeof b == 'number') {
if ( (b & 0xff) == b) {
// 1byte
bytes.push(b);
} else {
// 2bytes
bytes.push(b >>> 8);
bytes.push(b & 0xff);
}
} else {
bytes.push(unknownChar);
}
}
}
return bytes;
};
};
//---------------------------------------------------------------------
// QRMode
//---------------------------------------------------------------------
var QRMode = {
MODE_NUMBER : 1 << 0,
MODE_ALPHA_NUM : 1 << 1,
MODE_8BIT_BYTE : 1 << 2,
MODE_KANJI : 1 << 3
};
//---------------------------------------------------------------------
// QRErrorCorrectLevel
//---------------------------------------------------------------------
var QRErrorCorrectLevel = {
L : 1,
M : 0,
Q : 3,
H : 2
};
//---------------------------------------------------------------------
// QRMaskPattern
//---------------------------------------------------------------------
var QRMaskPattern = {
PATTERN000 : 0,
PATTERN001 : 1,
PATTERN010 : 2,
PATTERN011 : 3,
PATTERN100 : 4,
PATTERN101 : 5,
PATTERN110 : 6,
PATTERN111 : 7
};
//---------------------------------------------------------------------
// QRUtil
//---------------------------------------------------------------------
var QRUtil = function() {
var PATTERN_POSITION_TABLE = [
[],
[6, 18],
[6, 22],
[6, 26],
[6, 30],
[6, 34],
[6, 22, 38],
[6, 24, 42],
[6, 26, 46],
[6, 28, 50],
[6, 30, 54],
[6, 32, 58],
[6, 34, 62],
[6, 26, 46, 66],
[6, 26, 48, 70],
[6, 26, 50, 74],
[6, 30, 54, 78],
[6, 30, 56, 82],
[6, 30, 58, 86],
[6, 34, 62, 90],
[6, 28, 50, 72, 94],
[6, 26, 50, 74, 98],
[6, 30, 54, 78, 102],
[6, 28, 54, 80, 106],
[6, 32, 58, 84, 110],
[6, 30, 58, 86, 114],
[6, 34, 62, 90, 118],
[6, 26, 50, 74, 98, 122],
[6, 30, 54, 78, 102, 126],
[6, 26, 52, 78, 104, 130],
[6, 30, 56, 82, 108, 134],
[6, 34, 60, 86, 112, 138],
[6, 30, 58, 86, 114, 142],
[6, 34, 62, 90, 118, 146],
[6, 30, 54, 78, 102, 126, 150],
[6, 24, 50, 76, 102, 128, 154],
[6, 28, 54, 80, 106, 132, 158],
[6, 32, 58, 84, 110, 136, 162],
[6, 26, 54, 82, 110, 138, 166],
[6, 30, 58, 86, 114, 142, 170]
];
var G15 = (1 << 10) | (1 << 8) | (1 << 5) | (1 << 4) | (1 << 2) | (1 << 1) | (1 << 0);
var G18 = (1 << 12) | (1 << 11) | (1 << 10) | (1 << 9) | (1 << 8) | (1 << 5) | (1 << 2) | (1 << 0);
var G15_MASK = (1 << 14) | (1 << 12) | (1 << 10) | (1 << 4) | (1 << 1);
var _this = {};
var getBCHDigit = function(data) {
var digit = 0;
while (data != 0) {
digit += 1;
data >>>= 1;
}
return digit;
};
_this.getBCHTypeInfo = function(data) {
var d = data << 10;
while (getBCHDigit(d) - getBCHDigit(G15) >= 0) {
d ^= (G15 << (getBCHDigit(d) - getBCHDigit(G15) ) );
}
return ( (data << 10) | d) ^ G15_MASK;
};
_this.getBCHTypeNumber = function(data) {
var d = data << 12;
while (getBCHDigit(d) - getBCHDigit(G18) >= 0) {
d ^= (G18 << (getBCHDigit(d) - getBCHDigit(G18) ) );
}
return (data << 12) | d;
};
_this.getPatternPosition = function(typeNumber) {
return PATTERN_POSITION_TABLE[typeNumber - 1];
};
_this.getMaskFunction = function(maskPattern) {
switch (maskPattern) {
case QRMaskPattern.PATTERN000 :
return function(i, j) { return (i + j) % 2 == 0; };
case QRMaskPattern.PATTERN001 :
return function(i, j) { return i % 2 == 0; };
case QRMaskPattern.PATTERN010 :
return function(i, j) { return j % 3 == 0; };
case QRMaskPattern.PATTERN011 :
return function(i, j) { return (i + j) % 3 == 0; };
case QRMaskPattern.PATTERN100 :
return function(i, j) { return (Math.floor(i / 2) + Math.floor(j / 3) ) % 2 == 0; };
case QRMaskPattern.PATTERN101 :
return function(i, j) { return (i * j) % 2 + (i * j) % 3 == 0; };
case QRMaskPattern.PATTERN110 :
return function(i, j) { return ( (i * j) % 2 + (i * j) % 3) % 2 == 0; };
case QRMaskPattern.PATTERN111 :
return function(i, j) { return ( (i * j) % 3 + (i + j) % 2) % 2 == 0; };
default :
throw new Error('bad maskPattern:' + maskPattern);
}
};
_this.getErrorCorrectPolynomial = function(errorCorrectLength) {
var a = qrPolynomial([1], 0);
for (var i = 0; i < errorCorrectLength; i += 1) {
a = a.multiply(qrPolynomial([1, QRMath.gexp(i)], 0) );
}
return a;
};
_this.getLengthInBits = function(mode, type) {
if (1 <= type && type < 10) {
// 1 - 9
switch(mode) {
case QRMode.MODE_NUMBER : return 10;
case QRMode.MODE_ALPHA_NUM : return 9;
case QRMode.MODE_8BIT_BYTE : return 8;
case QRMode.MODE_KANJI : return 8;
default :
throw new Error('mode:' + mode);
}
} else if (type < 27) {
// 10 - 26
switch(mode) {
case QRMode.MODE_NUMBER : return 12;
case QRMode.MODE_ALPHA_NUM : return 11;
case QRMode.MODE_8BIT_BYTE : return 16;
case QRMode.MODE_KANJI : return 10;
default :
throw new Error('mode:' + mode);
}
} else if (type < 41) {
// 27 - 40
switch(mode) {
case QRMode.MODE_NUMBER : return 14;
case QRMode.MODE_ALPHA_NUM : return 13;
case QRMode.MODE_8BIT_BYTE : return 16;
case QRMode.MODE_KANJI : return 12;
default :
throw new Error('mode:' + mode);
}
} else {
throw new Error('type:' + type);
}
};
_this.getLostPoint = function(qrcode) {
var moduleCount = qrcode.getModuleCount();
var lostPoint = 0;
// LEVEL1
for (var row = 0; row < moduleCount; row += 1) {
for (var col = 0; col < moduleCount; col += 1) {
var sameCount = 0;
var dark = qrcode.isDark(row, col);
for (var r = -1; r <= 1; r += 1) {
if (row + r < 0 || moduleCount <= row + r) {
continue;
}
for (var c = -1; c <= 1; c += 1) {
if (col + c < 0 || moduleCount <= col + c) {
continue;
}
if (r == 0 && c == 0) {
continue;
}
if (dark == qrcode.isDark(row + r, col + c) ) {
sameCount += 1;
}
}
}
if (sameCount > 5) {
lostPoint += (3 + sameCount - 5);
}
}
};
// LEVEL2
for (var row = 0; row < moduleCount - 1; row += 1) {
for (var col = 0; col < moduleCount - 1; col += 1) {
var count = 0;
if (qrcode.isDark(row, col) ) count += 1;
if (qrcode.isDark(row + 1, col) ) count += 1;
if (qrcode.isDark(row, col + 1) ) count += 1;
if (qrcode.isDark(row + 1, col + 1) ) count += 1;
if (count == 0 || count == 4) {
lostPoint += 3;
}
}
}
// LEVEL3
for (var row = 0; row < moduleCount; row += 1) {
for (var col = 0; col < moduleCount - 6; col += 1) {
if (qrcode.isDark(row, col)
&& !qrcode.isDark(row, col + 1)
&& qrcode.isDark(row, col + 2)
&& qrcode.isDark(row, col + 3)
&& qrcode.isDark(row, col + 4)
&& !qrcode.isDark(row, col + 5)
&& qrcode.isDark(row, col + 6) ) {
lostPoint += 40;
}
}
}
for (var col = 0; col < moduleCount; col += 1) {
for (var row = 0; row < moduleCount - 6; row += 1) {
if (qrcode.isDark(row, col)
&& !qrcode.isDark(row + 1, col)
&& qrcode.isDark(row + 2, col)
&& qrcode.isDark(row + 3, col)
&& qrcode.isDark(row + 4, col)
&& !qrcode.isDark(row + 5, col)
&& qrcode.isDark(row + 6, col) ) {
lostPoint += 40;
}
}
}
// LEVEL4
var darkCount = 0;
for (var col = 0; col < moduleCount; col += 1) {
for (var row = 0; row < moduleCount; row += 1) {
if (qrcode.isDark(row, col) ) {
darkCount += 1;
}
}
}
var ratio = Math.abs(100 * darkCount / moduleCount / moduleCount - 50) / 5;
lostPoint += ratio * 10;
return lostPoint;
};
return _this;
}();
//---------------------------------------------------------------------
// QRMath
//---------------------------------------------------------------------
var QRMath = function() {
var EXP_TABLE = new Array(256);
var LOG_TABLE = new Array(256);
// initialize tables
for (var i = 0; i < 8; i += 1) {
EXP_TABLE[i] = 1 << i;
}
for (var i = 8; i < 256; i += 1) {
EXP_TABLE[i] = EXP_TABLE[i - 4]
^ EXP_TABLE[i - 5]
^ EXP_TABLE[i - 6]
^ EXP_TABLE[i - 8];
}
for (var i = 0; i < 255; i += 1) {
LOG_TABLE[EXP_TABLE[i] ] = i;
}
var _this = {};
_this.glog = function(n) {
if (n < 1) {
throw new Error('glog(' + n + ')');
}
return LOG_TABLE[n];
};
_this.gexp = function(n) {
while (n < 0) {
n += 255;
}
while (n >= 256) {
n -= 255;
}
return EXP_TABLE[n];
};
return _this;
}();
//---------------------------------------------------------------------
// qrPolynomial
//---------------------------------------------------------------------
function qrPolynomial(num, shift) {
if (typeof num.length == 'undefined') {
throw new Error(num.length + '/' + shift);
}
var _num = function() {
var offset = 0;
while (offset < num.length && num[offset] == 0) {
offset += 1;
}
var _num = new Array(num.length - offset + shift);
for (var i = 0; i < num.length - offset; i += 1) {
_num[i] = num[i + offset];
}
return _num;
}();
var _this = {};
_this.getAt = function(index) {
return _num[index];
};
_this.getLength = function() {
return _num.length;
};
_this.multiply = function(e) {
var num = new Array(_this.getLength() + e.getLength() - 1);
for (var i = 0; i < _this.getLength(); i += 1) {
for (var j = 0; j < e.getLength(); j += 1) {
num[i + j] ^= QRMath.gexp(QRMath.glog(_this.getAt(i) ) + QRMath.glog(e.getAt(j) ) );
}
}
return qrPolynomial(num, 0);
};
_this.mod = function(e) {
if (_this.getLength() - e.getLength() < 0) {
return _this;
}
var ratio = QRMath.glog(_this.getAt(0) ) - QRMath.glog(e.getAt(0) );
var num = new Array(_this.getLength() );
for (var i = 0; i < _this.getLength(); i += 1) {
num[i] = _this.getAt(i);
}
for (var i = 0; i < e.getLength(); i += 1) {
num[i] ^= QRMath.gexp(QRMath.glog(e.getAt(i) ) + ratio);
}
// recursive call
return qrPolynomial(num, 0).mod(e);
};
return _this;
};
//---------------------------------------------------------------------
// QRRSBlock
//---------------------------------------------------------------------
var QRRSBlock = function() {
// [1: [L, M, Q, H], ..]
var RS_BLOCK_TABLE=[[1,26,19],[1,26,16],[1,26,13],[1,26,9],[1,44,34],[1,44,28],[1,44,22],[1,44,16],[1,70,55],[1,70,44],[2,35,17],[2,35,13],[1,100,80],[2,50,32],[2,50,24],[4,25,9],[1,134,108],[2,67,43],[2,33,15,2,34,16],[2,33,11,2,34,12],[2,86,68],[4,43,27],[4,43,19],[4,43,15],[2,98,78],[4,49,31],[2,32,14,4,33,15],[4,39,13,1,40,14],[2,121,97],[2,60,38,2,61,39],[4,40,18,2,41,19],[4,40,14,2,41,15],[2,146,116],[3,58,36,2,59,37],[4,36,16,4,37,17],[4,36,12,4,37,13],[2,86,68,2,87,69],[4,69,43,1,70,44],[6,43,19,2,44,20],[6,43,15,2,44,16],[4,101,81],[1,80,50,4,81,51],[4,50,22,4,51,23],[3,36,12,8,37,13],[2,116,92,2,117,93],[6,58,36,2,59,37],[4,46,20,6,47,21],[7,42,14,4,43,15],[4,133,107],[8,59,37,1,60,38],[8,44,20,4,45,21],[12,33,11,4,34,12],[3,145,115,1,146,116],[4,64,40,5,65,41],[11,36,16,5,37,17],[11,36,12,5,37,13],[5,109,87,1,110,88],[5,65,41,5,66,42],[5,54,24,7,55,25],[11,36,12],[5,122,98,1,123,99],[7,73,45,3,74,46],[15,43,19,2,44,20],[3,45,15,13,46,16],[1,135,107,5,136,108],[10,74,46,1,75,47],[1,50,22,15,51,23],[2,42,14,17,43,15],[5,150,120,1,151,121],[9,69,43,4,70,44],[17,50,22,1,51,23],[2,42,14,19,43,15],[3,141,113,4,142,114],[3,70,44,11,71,45],[17,47,21,4,48,22],[9,39,13,16,40,14],[3,135,107,5,136,108],[3,67,41,13,68,42],[15,54,24,5,55,25],[15,43,15,10,44,16],[4,144,116,4,145,117],[17,68,42],[17,50,22,6,51,23],[19,46,16,6,47,17],[2,139,111,7,140,112],[17,74,46],[7,54,24,16,55,25],[34,37,13],[4,151,121,5,152,122],[4,75,47,14,76,48],[11,54,24,14,55,25],[16,45,15,14,46,16],[6,147,117,4,148,118],[6,73,45,14,74,46],[11,54,24,16,55,25],[30,46,16,2,47,17],[8,132,106,4,133,107],[8,75,47,13,76,48],[7,54,24,22,55,25],[22,45,15,13,46,16],[10,142,114,2,143,115],[19,74,46,4,75,47],[28,50,22,6,51,23],[33,46,16,4,47,17],[8,152,122,4,153,123],[22,73,45,3,74,46],[8,53,23,26,54,24],[12,45,15,28,46,16],[3,147,117,10,148,118],[3,73,45,23,74,46],[4,54,24,31,55,25],[11,45,15,31,46,16],[7,146,116,7,147,117],[21,73,45,7,74,46],[1,53,23,37,54,24],[19,45,15,26,46,16],[5,145,115,10,146,116],[19,75,47,10,76,48],[15,54,24,25,55,25],[23,45,15,25,46,16],[13,145,115,3,146,116],[2,74,46,29,75,47],[42,54,24,1,55,25],[23,45,15,28,46,16],[17,145,115],[10,74,46,23,75,47],[10,54,24,35,55,25],[19,45,15,35,46,16],[17,145,115,1,146,116],[14,74,46,21,75,47],[29,54,24,19,55,25],[11,45,15,46,46,16],[13,145,115,6,146,116],[14,74,46,23,75,47],[44,54,24,7,55,25],[59,46,16,1,47,17],[12,151,121,7,152,122],[12,75,47,26,76,48],[39,54,24,14,55,25],[22,45,15,41,46,16],[6,151,121,14,152,122],[6,75,47,34,76,48],[46,54,24,10,55,25],[2,45,15,64,46,16],[17,152,122,4,153,123],[29,74,46,14,75,47],[49,54,24,10,55,25],[24,45,15,46,46,16],[4,152,122,18,153,123],[13,74,46,32,75,47],[48,54,24,14,55,25],[42,45,15,32,46,16],[20,147,117,4,148,118],[40,75,47,7,76,48],[43,54,24,22,55,25],[10,45,15,67,46,16],[19,148,118,6,149,119],[18,75,47,31,76,48],[34,54,24,34,55,25],[20,45,15,61,46,16]];
var qrRSBlock = function(totalCount, dataCount) {
var _this = {};
_this.totalCount = totalCount;
_this.dataCount = dataCount;
return _this;
};
var _this = {};
var getRsBlockTable = function(typeNumber, errorCorrectLevel) {
switch(errorCorrectLevel) {
case QRErrorCorrectLevel.L :
return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 0];
case QRErrorCorrectLevel.M :
return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 1];
case QRErrorCorrectLevel.Q :
return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 2];
case QRErrorCorrectLevel.H :
return RS_BLOCK_TABLE[(typeNumber - 1) * 4 + 3];
default :
return undefined;
}
};
_this.getRSBlocks = function(typeNumber, errorCorrectLevel) {
var rsBlock = getRsBlockTable(typeNumber, errorCorrectLevel);
if (typeof rsBlock == 'undefined') {
throw new Error('bad rs block [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
};
小程序页面中生成二维码-wxqrcode
下载地址：链接: https://pan.baidu.com/s/1iEHNl-_F8kGwRDV-enMz5Q 密码: c4hm
项目参考：https://github.com/zenozeng/node-yaqrcode
1.基于canvas绘图制作二维码：https://github.com/demi520/wxapp-qrcode
2.基于img,base64输出二维码：https://git.oschina.net/cxing/wxqrcode.git
3.提供了不同语言的生成二维码： https://github.com/kazuhikoarase/qrcode-generator
4.二维码官网： http://www.qrcode.com/zh/
5.phpqrcode官网：http://phpqrcode.sourceforge.net/