uniapp/小程序实现Url生成二维码图片

更新日期: 2021-06-27阅读: 1.3k标签: uniapp

需求

使用uniapp开发的小程序,app应用,某一页面需要将网页Url生成的二维码进行展示,即将Url生成为base64的二维码图片。


页面js头部引用

var QR = require("../../utils/wxqrcode.js");


定义全局变量 

data: {
ewm: ''
},


使用QR.createQrCodeImg方法生成二维码

let url= "http://www.fly63.com/";
this.ewm= QR.createQrCodeImg(url, { size: 500 });


 页面内image引用

<image style="height: 5000rpx;width: 500rpx;" :src="ewm"></image>


wxqrcode.js源码

直接复制即可,网上下载的wxqrcode.js插件很多如果字符串过长,直接会报错,使用下面的将不会出现该情况。

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 @ 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 createQrCodeImg(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 = {};
module.exports = {
createQrCodeImg: createQrCodeImg
};



链接: https://fly63.com/article/detial/10453

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