在小程序中的使用：
utils文件夹下 barcode.js 粘粘以下代码
var CHAR_TILDE = 126 var CODE_FNC1 = 102 var SET_STARTA = 103 var SET_STARTB = 104 var SET_STARTC = 105 var SET_SHIFT = 98 var SET_CODEA = 101 var SET_CODEB = 100 var SET_STOP = 106 var REPLACE_CODES = { CHAR_TILDE: CODE_FNC1 // ~ corresponds to FNC1 in GS1-128 standard } var CODESET = { ANY: 1, AB: 2, A: 3, B: 4, C: 5 } function getBytes (str) { var bytes = [] for (var i = 0; i < str.length; i++) { bytes.push(str.charCodeAt(i)) } return bytes } exports.code128 = function (ctx, text, width, height) { width = parseInt(width) height = parseInt(height) var codes = stringToCode128(text) var g = new Graphics(ctx, width, height) var barWeight = g.area.width / ((codes.length - 3) * 11 + 35) var x = g.area.left var y = g.area.top for (var i = 0; i < codes.length; i++) { var c = codes[i] // two bars at a time: 1 black and 1 white for (var bar = 0; bar < 8; bar += 2) { var barW = PATTERNS[c][bar] * barWeight // var barH = height - y - this.border; var barH = height - y var spcW = PATTERNS[c][bar + 1] * barWeight // no need to draw if 0 width if (barW > 0) { g.fillFgRect(x, y, barW, barH) } x += barW + spcW } } ctx.draw() } function stringToCode128 (text) { var barc = { currcs: CODESET.C } var bytes = getBytes(text) // decide starting codeset var index = bytes[0] === CHAR_TILDE ? 1 : 0 var csa1 = bytes.length > 0 ? codeSetAllowedFor(bytes[index++]) : CODESET.AB var csa2 = bytes.length > 0 ? codeSetAllowedFor(bytes[index++]) : CODESET.AB barc.currcs = getBestStartSet(csa1, csa2) barc.currcs = perhapsCodeC(bytes, barc.currcs) // if no codeset changes this will end up with bytes.length+3 // start, checksum and stop var codes = [] switch (barc.currcs) { case CODESET.A: codes.push(SET_STARTA) break case CODESET.B: codes.push(SET_STARTB) break default: codes.push(SET_STARTC) break } for (var i = 0; i < bytes.length; i++) { var b1 = bytes[i] // get the first of a pair // should we translate/replace if (b1 in REPLACE_CODES) { codes.push(REPLACE_CODES[b1]) i++ // jump to next b1 = bytes[i] } // get the next in the pair if possible var b2 = bytes.length > (i + 1) ? bytes[i + 1] : -1 codes = codes.concat(codesForChar(b1, b2, barc.currcs)) // code C takes 2 chars each time if (barc.currcs === CODESET.C) i++ } // calculate checksum according to Code 128 standards var checksum = codes[0] for (var weight = 1; weight < codes.length; weight++) { checksum += (weight * codes[weight]) } codes.push(checksum % 103) codes.push(SET_STOP) // encoding should now be complete return codes function getBestStartSet (csa1, csa2) { // tries to figure out the best codeset // to start with to get the most compact code var vote = 0 vote += csa1 === CODESET.A ? 1 : 0 vote += csa1 === CODESET.B ? -1 : 0 vote += csa2 === CODESET.A ? 1 : 0 vote += csa2 === CODESET.B ? -1 : 0 // tie goes to B due to my own predudices return vote > 0 ? CODESET.A : CODESET.B } function perhapsCodeC (bytes, codeset) { for (var i = 0; i < bytes.length; i++) { var b = bytes[i] if ((b < 48 || b > 57) && b !== CHAR_TILDE) { return codeset } } return CODESET.C } // chr1 is current byte // chr2 is the next byte to process. looks ahead. function codesForChar (chr1, chr2, currcs) { var result = [] var shifter = -1 if (charCompatible(chr1, currcs)) { if (currcs === CODESET.C) { if (chr2 === -1) { shifter = SET_CODEB currcs = CODESET.B } else if ((chr2 !== -1) && !charCompatible(chr2, currcs)) { // need to check ahead as well if (charCompatible(chr2, CODESET.A)) { shifter = SET_CODEA currcs = CODESET.A } else { shifter = SET_CODEB currcs = CODESET.B } } } } else { // if there is a next char AND that next char is also not compatible if ((chr2 !== -1) && !charCompatible(chr2, currcs)) { // need to switch code sets switch (currcs) { case CODESET.A: shifter = SET_CODEB currcs = CODESET.B break case CODESET.B: shifter = SET_CODEA currcs = CODESET.A break } } else { // no need to shift code sets, a temporary SHIFT will suffice shifter = SET_SHIFT } } // ok some type of shift is nessecary if (shifter !== -1) { result.push(shifter) result.push(codeValue(chr1)) } else { if (currcs === CODESET.C) { // include next as well result.push(codeValue(chr1, chr2)) } else { result.push(codeValue(chr1)) } } barc.currcs = currcs return result } } // reduce the ascii code to fit into the Code128 char table function codeValue (chr1, chr2) { if (typeof chr2 === 'undefined') { return chr1 >= 32 ? chr1 - 32 : chr1 + 64 } else { return parseInt(String.fromCharCode(chr1) + String.fromCharCode(chr2)) } } function charCompatible (chr, codeset) { var csa = codeSetAllowedFor(chr) if (csa === CODESET.ANY) return true // if we need to change from current if (csa === CODESET.AB) return true if (csa === CODESET.A && codeset === CODESET.A) return true if (csa === CODESET.B && codeset === CODESET.B) return true return false } function codeSetAllowedFor (chr) { if (chr >= 48 && chr <= 57) { // 0-9 return CODESET.ANY } else if (chr >= 32 && chr <= 95) { // 0-9 A-Z return CODESET.AB } else { // if non printable return chr < 32 ? CODESET.A : CODESET.B } } var Graphics = function (ctx, width, height) { this.width = width this.height = height this.quiet = Math.round(this.width / 40) this.border_size = 0 this.padding_width = 0 this.area = { width - this.padding_width * 2 - this.quiet * 2, height: height - this.border_size * 2, top: this.border_size - 4, left: this.padding_width + this.quiet } this.ctx = ctx this.fg = '#000000' this.bg = '#ffffff' // fill background this.fillBgRect(0, 0, width, height) // fill center to create border this.fillBgRect(0, this.border_size, width, height - this.border_size * 2) } // use native color Graphics.prototype._fillRect = function (x, y, width, height, color) { this.ctx.setFillStyle(color) this.ctx.fillRect(x, y, width, height) } Graphics.prototype.fillFgRect = function (x, y, width, height) { this._fillRect(x, y, width, height, this.fg) } Graphics.prototype.fillBgRect = function (x, y, width, height) { this._fillRect(x, y, width, height, this.bg) } var PATTERNS = [ [2, 1, 2, 2, 2, 2, 0, 0], // 0 [2, 2, 2, 1, 2, 2, 0, 0], // 1 [2, 2, 2, 2, 2, 1, 0, 0], // 2 [1, 2, 1, 2, 2, 3, 0, 0], // 3 [1, 2, 1, 3, 2, 2, 0, 0], // 4 [1, 3, 1, 2, 2, 2, 0, 0], // 5 [1, 2, 2, 2, 1, 3, 0, 0], // 6 [1, 2, 2, 3, 1, 2, 0, 0], // 7 [1, 3, 2, 2, 1, 2, 0, 0], // 8 [2, 2, 1, 2, 1, 3, 0, 0], // 9 [2, 2, 1, 3, 1, 2, 0, 0], // 10 [2, 3, 1, 2, 1, 2, 0, 0], // 11 [1, 1, 2, 2, 3, 2, 0, 0], // 12 [1, 2, 2, 1, 3, 2, 0, 0], // 13 [1, 2, 2, 2, 3, 1, 0, 0], // 14 [1, 1, 3, 2, 2, 2, 0, 0], // 15 [1, 2, 3, 1, 2, 2, 0, 0], // 16 [1, 2, 3, 2, 2, 1, 0, 0], // 17 [2, 2, 3, 2, 1, 1, 0, 0], // 18 [2, 2, 1, 1, 3, 2, 0, 0], // 19 [2, 2, 1, 2, 3, 1, 0, 0], // 20 [2, 1, 3, 2, 1, 2, 0, 0], // 21 [2, 2, 3, 1, 1, 2, 0, 0], // 22 [3, 1, 2, 1, 3, 1, 0, 0], // 23 [3, 1, 1, 2, 2, 2, 0, 0], // 24 [3, 2, 1, 1, 2, 2, 0, 0], // 25 [3, 2, 1, 2, 2, 1, 0, 0], // 26 [3, 1, 2, 2, 1, 2, 0, 0], // 27 [3, 2, 2, 1, 1, 2, 0, 0], // 28 [3, 2, 2, 2, 1, 1, 0, 0], // 29 [2, 1, 2, 1, 2, 3, 0, 0], // 30 [2, 1, 2, 3, 2, 1, 0, 0], // 31 [2, 3, 2, 1, 2, 1, 0, 0], // 32 [1, 1, 1, 3, 2, 3, 0, 0], // 33 [1, 3, 1, 1, 2, 3, 0, 0], // 34 [1, 3, 1, 3, 2, 1, 0, 0], // 35 [1, 1, 2, 3, 1, 3, 0, 0], // 36 [1, 3, 2, 1, 1, 3, 0, 0], // 37 [1, 3, 2, 3, 1, 1, 0, 0], // 38 [2, 1, 1, 3, 1, 3, 0, 0], // 39 [2, 3, 1, 1, 1, 3, 0, 0], // 40 [2, 3, 1, 3, 1, 1, 0, 0], // 41 [1, 1, 2, 1, 3, 3, 0, 0], // 42 [1, 1, 2, 3, 3, 1, 0, 0], // 43 [1, 3, 2, 1, 3, 1, 0, 0], // 44 [1, 1, 3, 1, 2, 3, 0, 0], // 45 [1, 1, 3, 3, 2, 1, 0, 0], // 46 [1, 3, 3, 1, 2, 1, 0, 0], // 47 [3, 1, 3, 1, 2, 1, 0, 0], // 48 [2, 1, 1, 3, 3, 1, 0, 0], // 49 [2, 3, 1, 1, 3, 1, 0, 0], // 50 [2, 1, 3, 1, 1, 3, 0, 0], // 51 [2, 1, 3, 3, 1, 1, 0, 0], // 52 [2, 1, 3, 1, 3, 1, 0, 0], // 53 [3, 1, 1, 1, 2, 3, 0, 0], // 54 [3, 1, 1, 3, 2, 1, 0, 0], // 55 [3, 3, 1, 1, 2, 1, 0, 0], // 56 [3, 1, 2, 1, 1, 3, 0, 0], // 57 [3, 1, 2, 3, 1, 1, 0, 0], // 58 [3, 3, 2, 1, 1, 1, 0, 0], // 59 [3, 1, 4, 1, 1, 1, 0, 0], // 60 [2, 2, 1, 4, 1, 1, 0, 0], // 61 [4, 3, 1, 1, 1, 1, 0, 0], // 62 [1, 1, 1, 2, 2, 4, 0, 0], // 63 [1, 1, 1, 4, 2, 2, 0, 0], // 64 [1, 2, 1, 1, 2, 4, 0, 0], // 65 [1, 2, 1, 4, 2, 1, 0, 0], // 66 [1, 4, 1, 1, 2, 2, 0, 0], // 67 [1, 4, 1, 2, 2, 1, 0, 0], // 68 [1, 1, 2, 2, 1, 4, 0, 0], // 69 [1, 1, 2, 4, 1, 2, 0, 0], // 70 [1, 2, 2, 1, 1, 4, 0, 0], // 71 [1, 2, 2, 4, 1, 1, 0, 0], // 72 [1, 4, 2, 1, 1, 2, 0, 0], // 73 [1, 4, 2, 2, 1, 1, 0, 0], // 74 [2, 4, 1, 2, 1, 1, 0, 0], // 75 [2, 2, 1, 1, 1, 4, 0, 0], // 76 [4, 1, 3, 1, 1, 1, 0, 0], // 77 [2, 4, 1, 1, 1, 2, 0, 0], // 78 [1, 3, 4, 1, 1, 1, 0, 0], // 79 [1, 1, 1, 2, 4, 2, 0, 0], // 80 [1, 2, 1, 1, 4, 2, 0, 0], // 81 [1, 2, 1, 2, 4, 1, 0, 0], // 82 [1, 1, 4, 2, 1, 2, 0, 0], // 83 [1, 2, 4, 1, 1, 2, 0, 0], // 84 [1, 2, 4, 2, 1, 1, 0, 0], // 85 [4, 1, 1, 2, 1, 2, 0, 0], // 86 [4, 2, 1, 1, 1, 2, 0, 0], // 87 [4, 2, 1, 2, 1, 1, 0, 0], // 88 [2, 1, 2, 1, 4, 1, 0, 0], // 89 [2, 1, 4, 1, 2, 1, 0, 0], // 90 [4, 1, 2, 1, 2, 1, 0, 0], // 91 [1, 1, 1, 1, 4, 3, 0, 0], // 92 [1, 1, 1, 3, 4, 1, 0, 0], // 93 [1, 3, 1, 1, 4, 1, 0, 0], // 94 [1, 1, 4, 1, 1, 3, 0, 0], // 95 [1, 1, 4, 3, 1, 1, 0, 0], // 96 [4, 1, 1, 1, 1, 3, 0, 0], // 97 [4, 1, 1, 3, 1, 1, 0, 0], // 98 [1, 1, 3, 1, 4, 1, 0, 0], // 99 [1, 1, 4, 1, 3, 1, 0, 0], // 100 [3, 1, 1, 1, 4, 1, 0, 0], // 101 [4, 1, 1, 1, 3, 1, 0, 0], // 102 [2, 1, 1, 4, 1, 2, 0, 0], // 103 [2, 1, 1, 2, 1, 4, 0, 0], // 104 [2, 1, 1, 2, 3, 2, 0, 0], // 105 [2, 3, 3, 1, 1, 1, 2, 0] // 106 ]
utils文件夹下 index.js 放以下代码
var barcode = require('./barcode') function convertlength (length) { return Math.round(wx.getSystemInfoSync().windowWidth * length / 750) } function barc (id, code, width, height) { barcode.code128(wx.createCanvasContext(id), code, convertlength(width), convertlength(height)) } module.exports = { barcode: barc }
然后在小程序或mpvue中
<canvas canvas-id="barcode"></canvas> var barcode = require('@/utils/index') barcode.barcode('barcode', 'JsBarcode', 500, 350)
配置：
JsBarcode("#barcode", "123", {
format: "CODE39",//选择要使用的条形码类型
3,//设置条之间的宽度
height:100,//高度
displayValue:true,//是否在条形码下方显示文字
text:"456",//覆盖显示的文本
fontOptions:"bold italic",//使文字加粗体或变斜体
font:"fantasy",//设置文本的字体
textAlign:"left",//设置文本的水平对齐方式
textPosition:"top",//设置文本的垂直位置
textMargin:5,//设置条形码和文本之间的间距
fontSize:15,//设置文本的大小
background:"#eee",//设置条形码的背景
lineColor:"#2196f3",//设置条和文本的颜色。
margin:15//设置条形码周围的空白边距
});
官方：
https://github.com/lindell/JsBarcode/wiki/Options
参考： https://blog.csdn.net/huangpb123/article/details/82527344
如用到二维码：
下为：qrcode.js
(function () { // alignment pattern var adelta = [ 0, 11, 15, 19, 23, 27, 31, // force 1 pat 16, 18, 20, 22, 24, 26, 28, 20, 22, 24, 24, 26, 28, 28, 22, 24, 24, 26, 26, 28, 28, 24, 24, 26, 26, 26, 28, 28, 24, 26, 26, 26, 28, 28 ] // version block var vpat = [ 0xc94, 0x5bc, 0xa99, 0x4d3, 0xbf6, 0x762, 0x847, 0x60d, 0x928, 0xb78, 0x45d, 0xa17, 0x532, 0x9a6, 0x683, 0x8c9, 0x7ec, 0xec4, 0x1e1, 0xfab, 0x08e, 0xc1a, 0x33f, 0xd75, 0x250, 0x9d5, 0x6f0, 0x8ba, 0x79f, 0xb0b, 0x42e, 0xa64, 0x541, 0xc69 ] // final format bits with mask: level << 3 | mask var fmtword = [ 0x77c4, 0x72f3, 0x7daa, 0x789d, 0x662f, 0x6318, 0x6c41, 0x6976, // L 0x5412, 0x5125, 0x5e7c, 0x5b4b, 0x45f9, 0x40ce, 0x4f97, 0x4aa0, // M 0x355f, 0x3068, 0x3f31, 0x3a06, 0x24b4, 0x2183, 0x2eda, 0x2bed, // Q 0x1689, 0x13be, 0x1ce7, 0x19d0, 0x0762, 0x0255, 0x0d0c, 0x083b // H ] // 4 per version: number of blocks 1,2; data width; ecc width var eccblocks = [ 1, 0, 19, 7, 1, 0, 16, 10, 1, 0, 13, 13, 1, 0, 9, 17, 1, 0, 34, 10, 1, 0, 28, 16, 1, 0, 22, 22, 1, 0, 16, 28, 1, 0, 55, 15, 1, 0, 44, 26, 2, 0, 17, 18, 2, 0, 13, 22, 1, 0, 80, 20, 2, 0, 32, 18, 2, 0, 24, 26, 4, 0, 9, 16, 1, 0, 108, 26, 2, 0, 43, 24, 2, 2, 15, 18, 2, 2, 11, 22, 2, 0, 68, 18, 4, 0, 27, 16, 4, 0, 19, 24, 4, 0, 15, 28, 2, 0, 78, 20, 4, 0, 31, 18, 2, 4, 14, 18, 4, 1, 13, 26, 2, 0, 97, 24, 2, 2, 38, 22, 4, 2, 18, 22, 4, 2, 14, 26, 2, 0, 116, 30, 3, 2, 36, 22, 4, 4, 16, 20, 4, 4, 12, 24, 2, 2, 68, 18, 4, 1, 43, 26, 6, 2, 19, 24, 6, 2, 15, 28, 4, 0, 81, 20, 1, 4, 50, 30, 4, 4, 22, 28, 3, 8, 12, 24, 2, 2, 92, 24, 6, 2, 36, 22, 4, 6, 20, 26, 7, 4, 14, 28, 4, 0, 107, 26, 8, 1, 37, 22, 8, 4, 20, 24, 12, 4, 11, 22, 3, 1, 115, 30, 4, 5, 40, 24, 11, 5, 16, 20, 11, 5, 12, 24, 5, 1, 87, 22, 5, 5, 41, 24, 5, 7, 24, 30, 11, 7, 12, 24, 5, 1, 98, 24, 7, 3, 45, 28, 15, 2, 19, 24, 3, 13, 15, 30, 1, 5, 107, 28, 10, 1, 46, 28, 1, 15, 22, 28, 2, 17, 14, 28, 5, 1, 120, 30, 9, 4, 43, 26, 17, 1, 22, 28, 2, 19, 14, 28, 3, 4, 113, 28, 3, 11, 44, 26, 17, 4, 21, 26, 9, 16, 13, 26, 3, 5, 107, 28, 3, 13, 41, 26, 15, 5, 24, 30, 15, 10, 15, 28, 4, 4, 116, 28, 17, 0, 42, 26, 17, 6, 22, 28, 19, 6, 16, 30, 2, 7, 111, 28, 17, 0, 46, 28, 7, 16, 24, 30, 34, 0, 13, 24, 4, 5, 121, 30, 4, 14, 47, 28, 11, 14, 24, 30, 16, 14, 15, 30, 6, 4, 117, 30, 6, 14, 45, 28, 11, 16, 24, 30, 30, 2, 16, 30, 8, 4, 106, 26, 8, 13, 47, 28, 7, 22, 24, 30, 22, 13, 15, 30, 10, 2, 114, 28, 19, 4, 46, 28, 28, 6, 22, 28, 33, 4, 16, 30, 8, 4, 122, 30, 22, 3, 45, 28, 8, 26, 23, 30, 12, 28, 15, 30, 3, 10, 117, 30, 3, 23, 45, 28, 4, 31, 24, 30, 11, 31, 15, 30, 7, 7, 116, 30, 21, 7, 45, 28, 1, 37, 23, 30, 19, 26, 15, 30, 5, 10, 115, 30, 19, 10, 47, 28, 15, 25, 24, 30, 23, 25, 15, 30, 13, 3, 115, 30, 2, 29, 46, 28, 42, 1, 24, 30, 23, 28, 15, 30, 17, 0, 115, 30, 10, 23, 46, 28, 10, 35, 24, 30, 19, 35, 15, 30, 17, 1, 115, 30, 14, 21, 46, 28, 29, 19, 24, 30, 11, 46, 15, 30, 13, 6, 115, 30, 14, 23, 46, 28, 44, 7, 24, 30, 59, 1, 16, 30, 12, 7, 121, 30, 12, 26, 47, 28, 39, 14, 24, 30, 22, 41, 15, 30, 6, 14, 121, 30, 6, 34, 47, 28, 46, 10, 24, 30, 2, 64, 15, 30, 17, 4, 122, 30, 29, 14, 46, 28, 49, 10, 24, 30, 24, 46, 15, 30, 4, 18, 122, 30, 13, 32, 46, 28, 48, 14, 24, 30, 42, 32, 15, 30, 20, 4, 117, 30, 40, 7, 47, 28, 43, 22, 24, 30, 10, 67, 15, 30, 19, 6, 118, 30, 18, 31, 47, 28, 34, 34, 24, 30, 20, 61, 15, 30 ] // Galois field log table var glog = [ 0xff, 0x00, 0x01, 0x19, 0x02, 0x32, 0x1a, 0xc6, 0x03, 0xdf, 0x33, 0xee, 0x1b, 0x68, 0xc7, 0x4b, 0x04, 0x64, 0xe0, 0x0e, 0x34, 0x8d, 0xef, 0x81, 0x1c, 0xc1, 0x69, 0xf8, 0xc8, 0x08, 0x4c, 0x71, 0x05, 0x8a, 0x65, 0x2f, 0xe1, 0x24, 0x0f, 0x21, 0x35, 0x93, 0x8e, 0xda, 0xf0, 0x12, 0x82, 0x45, 0x1d, 0xb5, 0xc2, 0x7d, 0x6a, 0x27, 0xf9, 0xb9, 0xc9, 0x9a, 0x09, 0x78, 0x4d, 0xe4, 0x72, 0xa6, 0x06, 0xbf, 0x8b, 0x62, 0x66, 0xdd, 0x30, 0xfd, 0xe2, 0x98, 0x25, 0xb3, 0x10, 0x91, 0x22, 0x88, 0x36, 0xd0, 0x94, 0xce, 0x8f, 0x96, 0xdb, 0xbd, 0xf1, 0xd2, 0x13, 0x5c, 0x83, 0x38, 0x46, 0x40, 0x1e, 0x42, 0xb6, 0xa3, 0xc3, 0x48, 0x7e, 0x6e, 0x6b, 0x3a, 0x28, 0x54, 0xfa, 0x85, 0xba, 0x3d, 0xca, 0x5e, 0x9b, 0x9f, 0x0a, 0x15, 0x79, 0x2b, 0x4e, 0xd4, 0xe5, 0xac, 0x73, 0xf3, 0xa7, 0x57, 0x07, 0x70, 0xc0, 0xf7, 0x8c, 0x80, 0x63, 0x0d, 0x67, 0x4a, 0xde, 0xed, 0x31, 0xc5, 0xfe, 0x18, 0xe3, 0xa5, 0x99, 0x77, 0x26, 0xb8, 0xb4, 0x7c, 0x11, 0x44, 0x92, 0xd9, 0x23, 0x20, 0x89, 0x2e, 0x37, 0x3f, 0xd1, 0x5b, 0x95, 0xbc, 0xcf, 0xcd, 0x90, 0x87, 0x97, 0xb2, 0xdc, 0xfc, 0xbe, 0x61, 0xf2, 0x56, 0xd3, 0xab, 0x14, 0x2a, 0x5d, 0x9e, 0x84, 0x3c, 0x39, 0x53, 0x47, 0x6d, 0x41, 0xa2, 0x1f, 0x2d, 0x43, 0xd8, 0xb7, 0x7b, 0xa4, 0x76, 0xc4, 0x17, 0x49, 0xec, 0x7f, 0x0c, 0x6f, 0xf6, 0x6c, 0xa1, 0x3b, 0x52, 0x29, 0x9d, 0x55, 0xaa, 0xfb, 0x60, 0x86, 0xb1, 0xbb, 0xcc, 0x3e, 0x5a, 0xcb, 0x59, 0x5f, 0xb0, 0x9c, 0xa9, 0xa0, 0x51, 0x0b, 0xf5, 0x16, 0xeb, 0x7a, 0x75, 0x2c, 0xd7, 0x4f, 0xae, 0xd5, 0xe9, 0xe6, 0xe7, 0xad, 0xe8, 0x74, 0xd6, 0xf4, 0xea, 0xa8, 0x50, 0x58, 0xaf ] // Galios field exponent table var gexp = [ 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1d, 0x3a, 0x74, 0xe8, 0xcd, 0x87, 0x13, 0x26, 0x4c, 0x98, 0x2d, 0x5a, 0xb4, 0x75, 0xea, 0xc9, 0x8f, 0x03, 0x06, 0x0c, 0x18, 0x30, 0x60, 0xc0, 0x9d, 0x27, 0x4e, 0x9c, 0x25, 0x4a, 0x94, 0x35, 0x6a, 0xd4, 0xb5, 0x77, 0xee, 0xc1, 0x9f, 0x23, 0x46, 0x8c, 0x05, 0x0a, 0x14, 0x28, 0x50, 0xa0, 0x5d, 0xba, 0x69, 0xd2, 0xb9, 0x6f, 0xde, 0xa1, 0x5f, 0xbe, 0x61, 0xc2, 0x99, 0x2f, 0x5e, 0xbc, 0x65, 0xca, 0x89, 0x0f, 0x1e, 0x3c, 0x78, 0xf0, 0xfd, 0xe7, 0xd3, 0xbb, 0x6b, 0xd6, 0xb1, 0x7f, 0xfe, 0xe1, 0xdf, 0xa3, 0x5b, 0xb6, 0x71, 0xe2, 0xd9, 0xaf, 0x43, 0x86, 0x11, 0x22, 0x44, 0x88, 0x0d, 0x1a, 0x34, 0x68, 0xd0, 0xbd, 0x67, 0xce, 0x81, 0x1f, 0x3e, 0x7c, 0xf8, 0xed, 0xc7, 0x93, 0x3b, 0x76, 0xec, 0xc5, 0x97, 0x33, 0x66, 0xcc, 0x85, 0x17, 0x2e, 0x5c, 0xb8, 0x6d, 0xda, 0xa9, 0x4f, 0x9e, 0x21, 0x42, 0x84, 0x15, 0x2a, 0x54, 0xa8, 0x4d, 0x9a, 0x29, 0x52, 0xa4, 0x55, 0xaa, 0x49, 0x92, 0x39, 0x72, 0xe4, 0xd5, 0xb7, 0x73, 0xe6, 0xd1, 0xbf, 0x63, 0xc6, 0x91, 0x3f, 0x7e, 0xfc, 0xe5, 0xd7, 0xb3, 0x7b, 0xf6, 0xf1, 0xff, 0xe3, 0xdb, 0xab, 0x4b, 0x96, 0x31, 0x62, 0xc4, 0x95, 0x37, 0x6e, 0xdc, 0xa5, 0x57, 0xae, 0x41, 0x82, 0x19, 0x32, 0x64, 0xc8, 0x8d, 0x07, 0x0e, 0x1c, 0x38, 0x70, 0xe0, 0xdd, 0xa7, 0x53, 0xa6, 0x51, 0xa2, 0x59, 0xb2, 0x79, 0xf2, 0xf9, 0xef, 0xc3, 0x9b, 0x2b, 0x56, 0xac, 0x45, 0x8a, 0x09, 0x12, 0x24, 0x48, 0x90, 0x3d, 0x7a, 0xf4, 0xf5, 0xf7, 0xf3, 0xfb, 0xeb, 0xcb, 0x8b, 0x0b, 0x16, 0x2c, 0x58, 0xb0, 0x7d, 0xfa, 0xe9, 0xcf, 0x83, 0x1b, 0x36, 0x6c, 0xd8, 0xad, 0x47, 0x8e, 0x00 ] // Working buffers: // data input and ecc append, image working buffer, fixed part of image, run lengths for badness var strinbuf = [] var eccbuf = [] var qrframe = [] var framask = [] var rlens = [] // Control values - width is based on version, last 4 are from table. var version, width, neccblk1, neccblk2, datablkw, eccblkwid var ecclevel = 2 // set bit to indicate cell in qrframe is immutable. symmetric around diagonal function setmask (x, y) { var bt if (x > y) { bt = x x = y y = bt } // y*y = 1+3+5... bt = y bt *= y bt += y bt >>= 1 bt += x framask[bt] = 1 } // enter alignment pattern - black to qrframe, white to mask (later black frame merged to mask) function putalign (x, y) { var j qrframe[x + width * y] = 1 for (j = -2; j < 2; j++) { qrframe[(x + j) + width * (y - 2)] = 1 qrframe[(x - 2) + width * (y + j + 1)] = 1 qrframe[(x + 2) + width * (y + j)] = 1 qrframe[(x + j + 1) + width * (y + 2)] = 1 } for (j = 0; j < 2; j++) { setmask(x - 1, y + j) setmask(x + 1, y - j) setmask(x - j, y - 1) setmask(x + j, y + 1) } } //= ======================================================================= // Reed Solomon error correction // exponentiation mod N function modnn (x) { while (x >= 255) { x -= 255 x = (x >> 8) + (x & 255) } return x } var genpoly = [] // Calculate and append ECC data to data block. Block is in strinbuf, indexes to buffers given. function appendrs (data, dlen, ecbuf, eclen) { var i, j, fb for (i = 0; i < eclen; i++) { strinbuf[ecbuf + i] = 0 } for (i = 0; i < dlen; i++) { fb = glog[strinbuf[data + i] ^ strinbuf[ecbuf]] if (fb !== 255) { for (j = 1; j < eclen; j++) { strinbuf[ecbuf + j - 1] = strinbuf[ecbuf + j] ^ gexp[modnn(fb + genpoly[eclen - j])] } } else { for (j = ecbuf; j < ecbuf + eclen; j++) { strinbuf[j] = strinbuf[j + 1] } } strinbuf[ecbuf + eclen - 1] = fb === 255 ? 0 : gexp[modnn(fb + genpoly[0])] } } //= ======================================================================= // Frame data insert following the path rules // check mask - since symmetrical use half. function ismasked (x, y) { var bt if (x > y) { bt = x x = y y = bt } bt = y bt += y * y bt >>= 1 bt += x return framask[bt] } //= ======================================================================= // Apply the selected mask out of the 8. function applymask (m) { var x, y, r3x, r3y switch (m) { case 0: for (y = 0; y < width; y++) { for (x = 0; x < width; x++) { if (!((x + y) & 1) && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 1: for (y = 0; y < width; y++) { for (x = 0; x < width; x++) { if (!(y & 1) && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 2: for (y = 0; y < width; y++) { for (r3x = 0, x = 0; x < width; x++, r3x++) { if (r3x === 3) { r3x = 0 } if (!r3x && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 3: for (r3y = 0, y = 0; y < width; y++, r3y++) { if (r3y === 3) { r3y = 0 } for (r3x = r3y, x = 0; x < width; x++, r3x++) { if (r3x === 3) { r3x = 0 } if (!r3x && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 4: for (y = 0; y < width; y++) { for (r3x = 0, r3y = ((y >> 1) & 1), x = 0; x < width; x++, r3x++) { if (r3x === 3) { r3x = 0 r3y = !r3y } if (!r3y && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 5: for (r3y = 0, y = 0; y < width; y++, r3y++) { if (r3y === 3) { r3y = 0 } for (r3x = 0, x = 0; x < width; x++, r3x++) { if (r3x === 3) { r3x = 0 } if (!((x & y & 1) + !(!r3x | !r3y)) && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 6: for (r3y = 0, y = 0; y < width; y++, r3y++) { if (r3y === 3) { r3y = 0 } for (r3x = 0, x = 0; x < width; x++, r3x++) { if (r3x === 3) { r3x = 0 } if (!(((x & y & 1) + (r3x && (r3x === r3y))) & 1) && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break case 7: for (r3y = 0, y = 0; y < width; y++, r3y++) { if (r3y === 3) { r3y = 0 } for (r3x = 0, x = 0; x < width; x++, r3x++) { if (r3x === 3) { r3x = 0 } if (!(((r3x && (r3x === r3y)) + ((x + y) & 1)) & 1) && !ismasked(x, y)) { qrframe[x + y * width] ^= 1 } } } break } } // Badness coefficients. var N1 = 3 var N2 = 3 var N3 = 40 var N4 = 10 // Using the table of the length of each run, calculate the amount of bad image // - long runs or those that look like finders; called twice, once each for X and Y function badruns (length) { var i var runsbad = 0 for (i = 0; i <= length; i++) { if (rlens[i] >= 5) { runsbad += N1 + rlens[i] - 5 } } // BwBBBwB as in finder for (i = 3; i < length - 1; i += 2) { if (rlens[i - 2] === rlens[i + 2] && rlens[i + 2] === rlens[i - 1] && rlens[i - 1] === rlens[i + 1] && rlens[i - 1] * 3 === rlens[i] && // white around the black pattern? Not part of spec (rlens[i - 3] === 0 || // beginning i + 3 > length || // end rlens[i - 3] * 3 >= rlens[i] * 4 || rlens[i + 3] * 3 >= rlens[i] * 4) ) { runsbad += N3 } } return runsbad } // Calculate how bad the masked image is - blocks, imbalance, runs, or finders. function badcheck () { var x, y, h, b, b1 var thisbad = 0 var bw = 0 // blocks of same color. for (y = 0; y < width - 1; y++) { for (x = 0; x < width - 1; x++) { if ((qrframe[x + width * y] && qrframe[(x + 1) + width * y] && qrframe[x + width * (y + 1)] && qrframe[(x + 1) + width * (y + 1)]) || // all black !(qrframe[x + width * y] || qrframe[(x + 1) + width * y] || qrframe[x + width * (y + 1)] || qrframe[(x + 1) + width * (y + 1)])) { thisbad += N2 } } } // X runs for (y = 0; y < width; y++) { rlens[0] = 0 for (h = b = x = 0; x < width; x++) { if ((b1 = qrframe[x + width * y]) === b) { rlens[h]++ } else { rlens[++h] = 1 } b = b1 bw += b ? 1 : -1 } thisbad += badruns(h) } // black/white imbalance if (bw < 0) { bw = -bw } var big = bw var count = 0 big += big << 2 big <<= 1 while (big > width * width) { big -= width * width count++ } thisbad += count * N4 // Y runs for (x = 0; x < width; x++) { rlens[0] = 0 for (h = b = y = 0; y < width; y++) { if ((b1 = qrframe[x + width * y]) === b) { rlens[h]++ } else { rlens[++h] = 1 } b = b1 } thisbad += badruns(h) } return thisbad } function genframe (instring) { var x, y, k, t, v, i, j, m // find the smallest version that fits the string t = instring.length version = 0 do { version++ k = (ecclevel - 1) * 4 + (version - 1) * 16 neccblk1 = eccblocks[k++] neccblk2 = eccblocks[k++] datablkw = eccblocks[k++] eccblkwid = eccblocks[k] k = datablkw * (neccblk1 + neccblk2) + neccblk2 - 3 + (version <= 9) if (t <= k) { break } } while (version < 40) // FIXME - insure that it fits insted of being truncated width = 17 + 4 * version // allocate, clear and setup data structures v = datablkw + (datablkw + eccblkwid) * (neccblk1 + neccblk2) + neccblk2 for (t = 0; t < v; t++) { eccbuf[t] = 0 } strinbuf = instring.slice(0) for (t = 0; t < width * width; t++) { qrframe[t] = 0 } for (t = 0; t < (width * (width + 1) + 1) / 2; t++) { framask[t] = 0 } // insert finders - black to frame, white to mask for (t = 0; t < 3; t++) { k = 0 y = 0 if (t === 1) { k = (width - 7) } if (t === 2) { y = (width - 7) } qrframe[(y + 3) + width * (k + 3)] = 1 for (x = 0; x < 6; x++) { qrframe[(y + x) + width * k] = 1 qrframe[y + width * (k + x + 1)] = 1 qrframe[(y + 6) + width * (k + x)] = 1 qrframe[(y + x + 1) + width * (k + 6)] = 1 } for (x = 1; x < 5; x++) { setmask(y + x, k + 1) setmask(y + 1, k + x + 1) setmask(y + 5, k + x) setmask(y + x + 1, k + 5) } for (x = 2; x < 4; x++) { qrframe[(y + x) + width * (k + 2)] = 1 qrframe[(y + 2) + width * (k + x + 1)] = 1 qrframe[(y + 4) + width * (k + x)] = 1 qrframe[(y + x + 1) + width * (k + 4)] = 1 } } // alignment blocks if (version > 1) { t = adelta[version] y = width - 7 for (;;) { x = width - 7 while (x > t - 3) { putalign(x, y) if (x < t) { break } x -= t } if (y <= t + 9) { break } y -= t putalign(6, y) putalign(y, 6) } } // single black qrframe[8 + width * (width - 8)] = 1 // timing gap - mask only for (y = 0; y < 7; y++) { setmask(7, y) setmask(width - 8, y) setmask(7, y + width - 7) } for (x = 0; x < 8; x++) { setmask(x, 7) setmask(x + width - 8, 7) setmask(x, width - 8) } // reserve mask-format area for (x = 0; x < 9; x++) { setmask(x, 8) } for (x = 0; x < 8; x++) { setmask(x + width - 8, 8) setmask(8, x) } for (y = 0; y < 7; y++) { setmask(8, y + width - 7) } // timing row/col for (x = 0; x < width - 14; x++) { if (x & 1) { setmask(8 + x, 6) setmask(6, 8 + x) } else { qrframe[(8 + x) + width * 6] = 1 qrframe[6 + width * (8 + x)] = 1 } } // version block if (version > 6) { t = vpat[version - 7] k = 17 for (x = 0; x < 6; x++) { for (y = 0; y < 3; y++, k--) { if (1 & (k > 11 ? version >> (k - 12) : t >> k)) { qrframe[(5 - x) + width * (2 - y + width - 11)] = 1 qrframe[(2 - y + width - 11) + width * (5 - x)] = 1 } else { setmask(5 - x, 2 - y + width - 11) setmask(2 - y + width - 11, 5 - x) } } } } // sync mask bits - only set above for white spaces, so add in black bits for (y = 0; y < width; y++) { for (x = 0; x <= y; x++) { if (qrframe[x + width * y]) { setmask(x, y) } } } // convert string to bitstream // 8 bit data to QR-coded 8 bit data (numeric or alphanum, or kanji not supported) v = strinbuf.length // string to array for (i = 0; i < v; i++) { eccbuf[i] = strinbuf.charCodeAt(i) } strinbuf = eccbuf.slice(0) // calculate max string length x = datablkw * (neccblk1 + neccblk2) + neccblk2 if (v >= x - 2) { v = x - 2 if (version > 9) { v-- } } // shift and repack to insert length prefix i = v if (version > 9) { strinbuf[i + 2] = 0 strinbuf[i + 3] = 0 while (i--) { t = strinbuf[i] strinbuf[i + 3] |= 255 & (t << 4) strinbuf[i + 2] = t >> 4 } strinbuf[2] |= 255 & (v << 4) strinbuf[1] = v >> 4 strinbuf[0] = 0x40 | (v >> 12) } else { strinbuf[i + 1] = 0 strinbuf[i + 2] = 0 while (i--) { t = strinbuf[i] strinbuf[i + 2] |= 255 & (t << 4) strinbuf[i + 1] = t >> 4 } strinbuf[1] |= 255 & (v << 4) strinbuf[0] = 0x40 | (v >> 4) } // fill to end with pad pattern i = v + 3 - (version < 10) while (i < x) { strinbuf[i++] = 0xec // buffer has room if (i === x) break; strinbuf[i++] = 0x11 } // calculate and append ECC // calculate generator polynomial genpoly[0] = 1 for (i = 0; i < eccblkwid; i++) { genpoly[i + 1] = 1 for (j = i; j > 0; j--) { genpoly[j] = genpoly[j] ? genpoly[j - 1] ^ gexp[modnn(glog[genpoly[j]] + i)] : genpoly[j - 1] } genpoly[0] = gexp[modnn(glog[genpoly[0]] + i)] } for (i = 0; i <= eccblkwid; i++) { genpoly[i] = glog[genpoly[i]] } // use logs for genpoly[] to save calc step // append ecc to data buffer k = x y = 0 for (i = 0; i < neccblk1; i++) { appendrs(y, datablkw, k, eccblkwid) y += datablkw k += eccblkwid } for (i = 0; i < neccblk2; i++) { appendrs(y, datablkw + 1, k, eccblkwid) y += datablkw + 1 k += eccblkwid } // interleave blocks y = 0 for (i = 0; i < datablkw; i++) { for (j = 0; j < neccblk1; j++) { eccbuf[y++] = strinbuf[i + j * datablkw] } for (j = 0; j < neccblk2; j++) { eccbuf[y++] = strinbuf[(neccblk1 * datablkw) + i + (j * (datablkw + 1))] } } for (j = 0; j < neccblk2; j++) { eccbuf[y++] = strinbuf[(neccblk1 * datablkw) + i + (j * (datablkw + 1))] } for (i = 0; i < eccblkwid; i++) { for (j = 0; j < neccblk1 + neccblk2; j++) { eccbuf[y++] = strinbuf[x + i + j * eccblkwid] } } strinbuf = eccbuf // pack bits into frame avoiding masked area. x = y = width - 1 k = v = 1 // up, minus /* inteleaved data and ecc codes */ m = (datablkw + eccblkwid) * (neccblk1 + neccblk2) + neccblk2 for (i = 0; i < m; i++) { t = strinbuf[i] for (j = 0; j < 8; j++, t <<= 1) { if (0x80 & t) { qrframe[x + width * y] = 1 } do { // find next fill position if (v) { x-- } else { x++ if (k) { if (y !== 0) { y-- } else { x -= 2 k = !k if (x === 6) { x-- y = 9 } } } else { if (y !== width - 1) { y++ } else { x -= 2 k = !k if (x === 6) { x-- y -= 8 } } } } v = !v } while (ismasked(x, y)) } } // save pre-mask copy of frame strinbuf = qrframe.slice(0) t = 0 // best y = 30000 // demerit // for instead of while since in original arduino code // if an early mask was "good enough" it wouldn't try for a better one // since they get more complex and take longer. for (k = 0; k < 8; k++) { applymask(k) // returns black-white imbalance x = badcheck() if (x < y) { // current mask better than previous best? y = x t = k } if (t === 7) { break } // don't increment i to a void redoing mask qrframe = strinbuf.slice(0) // reset for next pass } if (t !== k) { applymask(t) } // add in final mask/ecclevel bytes y = fmtword[t + ((ecclevel - 1) << 3)] // low byte for (k = 0; k < 8; k++, y >>= 1) { if (y & 1) { qrframe[(width - 1 - k) + width * 8] = 1 if (k < 6) { qrframe[8 + width * k] = 1 } else { qrframe[8 + width * (k + 1)] = 1 } } } // high byte for (k = 0; k < 7; k++, y >>= 1) { if (y & 1) { qrframe[8 + width * (width - 7 + k)] = 1 if (k) { qrframe[(6 - k) + width * 8] = 1 } else { qrframe[7 + width * 8] = 1 } } } // return image return qrframe } var _canvas = null var _size = null var api = { get ecclevel () { return ecclevel }, set ecclevel (val) { ecclevel = val }, get size () { return _size }, set size (val) { _size = val }, get canvas () { return _canvas }, set canvas (el) { _canvas = el }, getFrame: function (string) { return genframe(string) }, draw: function (string, canvas, size, ecc) { ecclevel = ecc || ecclevel canvas = canvas || _canvas if (!canvas) { console.warn('No canvas provided to draw QR code in!') return } size = size || _size || Math.min(canvas.width, canvas.height) var frame = genframe(string) var ctx = canvas.ctx var px = Math.round(size / (width + 8)) var roundedSize = px * (width + 8) var offset = Math.floor((size - roundedSize) / 2) size = roundedSize ctx.clearRect(0, 0, canvas.width, canvas.height) ctx.setFillStyle('#000000') for (var i = 0; i < width; i++) { for (var j = 0; j < width; j++) { if (frame[j * width + i]) { ctx.fillRect(px * (4 + i) + offset, px * (4 + j) + offset, px, px) } } } ctx.draw() } } module.exports = { api: api } })()
使用同条形码一样，引入时可放一起
var qrcode = require('./qrcode') function convertlength (length) { return Math.round(wx.getSystemInfoSync().windowWidth * length / 750) } function qrc (id, code, width, height) { qrcode.api.draw(code, { ctx: wx.createCanvasContext(id), convertlength(width), height: convertlength(height) }) } module.exports = { qrcode: qrc }
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