原文:https://blog.csdn.net/xbw12138/article/details/75213274

前端 
二维码生成 
二维码要求:每分钟刷新一次,模拟了个鸡肋,添加了个按分钟显示的时间加在二维码中,起到刷新的作用,在onshow中每次打开界面就会刷新显示

var QR = require("../../utils/qrcode.js");
var util = require("../../utils/util.js");
data: {
qrMsg: '',
recognizeMsg: '',
isShowMsg: false,
isShowResult: false,
showClear: true,
qrlogin :false,
},
onShow: function () {
var that=this;
this.setData({
isShowMsg: false,
isShowResult: true,
})
// 页面显示,用户已注册
if (getApp().globalData.userSign == 1) {
that.setData({
qrlogin: true,
})
//存储openid
wx.getStorage({
key: 'openid',
success: function (res) {
var openid = res.data;
//加入分钟,每分钟刷新一次二维码
QR.qrApi.draw('wechat@'+openid + '@' + util.formatTimeQrcodeChange(new Date), 'mycanvas', 300, 300)
}
})
} else if (getApp().globalData.userSign == 2){
that.setData({
qrlogin:false,
})
}
},

扫描二维码

recognizeCode: function () {
this.setData({
isShowMsg: true,
isShowResult: false,
recognizeMsg: "",
})
var that = this
//小程序API
wx.scanCode({
//扫描条形码ISBN
success: function (res) {
// success
console.log('https://book.douban.com/subject/' + res.result+'/');
var url = 'https://book.douban.com/subject/' + res.result + '/';
wx.navigateTo({
url: '../desc/desc?url=' + url
})
},
fail: function () {
// fail
},
complete: function () {
// complete
}
})
},

utils.js中添加以下代码

function formatTimeQrcodeChange(date) {
var year = date.getFullYear()
var month = date.getMonth() + 1
var day = date.getDate() var hour = date.getHours()
var minute = date.getMinutes()
//按分钟显示,去掉秒
//var second = date.getSeconds()
return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute].map(formatNumber).join(':')
}

qrcode.js

var QR = (function () {

    // alignment pattern
var adelta = [
0, 11, 15, 19, 23, 27, 31,
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=[], eccbuf=[], qrframe=[], framask=[], 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) /* fb term is non-zero */
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;
}
return;
} // Badness coefficients.
var N1 = 3, N2 = 3, N3 = 40, 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)])) // all white
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) // redo best mask - none good enough, last wasn't t
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 qrframe;
} var _canvas = 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);
},
//这里的utf16to8(str)是对Text中的字符串进行转码,让其支持中文
utf16to8:function(str) {
var out, i, len, c; out = "";
len = str.length;
for(i = 0; i < len; i++) {
c = str.charCodeAt(i);
if ((c >= 0x0001) && (c <= 0x007F)) {
out += str.charAt(i);
} else if (c > 0x07FF) {
out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
} else {
out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
}
}
return out;
}, draw: function (str, canvas, cavW, cavH, ecc) { ecclevel = ecc || ecclevel;
canvas = canvas || _canvas;
if (!canvas) {
console.warn('No canvas provided to draw QR code in!')
return;
} var size = Math.min(cavW, cavH);
str = this.utf16to8(str);//增加中文显示
console.log(str)
var frame = this.getFrame(str),
ctx = wx.createCanvasContext(canvas),
px = Math.round(size / (width + 8));
var roundedSize = px * (width + 8),
offset = Math.floor((size - roundedSize) / 2);
size = roundedSize;
ctx.clearRect(0, 0, cavW, cavW);
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 = {
qrApi: api
} })();

wxml

<view class="container-box">
<!--识别器-->
<view class="home-section">
<view class="home-section-title" bindtap="recognizeCode">
<text class="home-section-title-recognize">添加书籍到预定单</text>
<image class="home-next-btn" src="../../images/scan2.png"></image>
</view>
</view>
<view class="home-section">
<view class="home-section-title" bindtap="payDeposit">
<text class="home-section-title-recognize">支付押金</text>
<image class="home-next-btn" src="../../images/pay.png"></image>
</view>
</view> <view class="qrcode-box">
<view class="qrcode-container">
<view class="qrcode-top">
<text>借书请出示此码</text>
</view>
<canvas bindtap="previewImg" canvas-id="mycanvas" class="qrcode"/>
<view hidden="{{qrlogin}}"><text>需要注册用户信息后方可显示二维码</text></view>
<view class="qrcode-bottom">
<view>请勿将此码暴露</view>
</view>
</view>
</view>
</view>

wxss

.home-section-title {
background-color: #F9F9F9;
display: flex;
flex-direction: row;
justify-content: space-between;
align-items: center;
height: 120rpx;
border-radius: 10rpx;
} .home-section-title-make {
color: #217834;
padding-left: 30rpx;
}
.recognize-content {
/*padding: 10px;*/
}
.recognize-content-hidden {
padding: 10px;
color: #e5e5e5;
} .home-section-title-recognize {
color: #217834;
padding-left: 30rpx;
} .home-next-btn {
margin-right: 30rpx;
height: 45rpx;
width: 45rpx;
} .container-box{
background-color: #fff;
height: 100vh;
flex-direction: column;
align-items: center;
padding-top: 0rpx; } .home-section {
background-color: white;
margin: 30rpx;
border-radius: 10rpx; } .recog-text {
font-size-adjust: true
}
.home-clear {
font-size: x-small;
color: #ff7069;
font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif;
margin-right: 10px;
height: 20px;
text-align: center;
display: flex;
justify-content: flex-end;
} .qrcode-box {
display: flex;
flex-direction: column;
justify-content: center;
align-items: center;
padding-top: 0rpx;
background-color: #fff;
} page{
height: 100%;
} .qrcode-container {
display: flex;
flex-direction: column;
align-items: center;
margin-top: 0px;
background-color: #e5e5e5;
border-radius: 20rpx;
} .qrcode {
width: 300px;
height: 300px;
background-color: white;
} .qrcode-top {
min-height: 50px;
/*font-size: xx-large;*/
display: flex;
justify-content: center;
align-items: center;
flex-direction: column;
/*color: #ff7069;*/
color: #217834;
} .qrcode-bottom {
min-height: 50px;
width: 100%;
font-size: small;
display: flex;
justify-content: center;
align-content: center;
color: gray;
flex-direction: column;
text-align: center;
}

转【微信小程序 四】二维码生成/扫描二维码的更多相关文章

  1. 解决Mac版微信小程序开发工具打开后无法显示二维码

    问题描述: 正常情况下,打开微信小程序开发工具后,首页提示扫描二维码进行登陆,但是如果不显示二维码,当然无法登陆. 解决方案: 无法显示二维码肯定是程序运行哪里出错了,我们直接点击桌面图标是无法排查错 ...

  2. 微信小程序开发——使用第三方插件生成二维码

    需求场景: 小程序中指定页面需要根据列表数据生成多张二维码. 实现方案: 鉴于需要生成多张二维码,可以将生成二维码的功能封装到组件中,直接在页面列表循环中调用就好了.也可以给组件添加slot,在页面调 ...

  3. 微信小程序——表单验证插件WxValidate的二次封装(二)

    在上一篇博客<微信小程序——仿jqueryValidate表单验证插件WxValidate的二次封装>中,我将WxValidate做了再次封装,简化了初始规则数据的构造,但是当有错误时页面 ...

  4. 微信小程序——表单验证插件WxValidate的二次封装(终极版)

    微信小程序表单验证前面的两篇文章做的效果总感觉都有点不太友好,第一篇里的效果是将错误信息通过对话框形式弹出来,这种形式在web形式下早已经淘汰了:第二篇是一次性全部显示所有的错误,然后3秒后自动消失, ...

  5. 【微信小程序】获取用户地理位置权限,二次请求授权,逆解析获取地址

    摘要:微信小程序内获取用户地理位置信息授权,被拒绝后二次获取,获取权限后逆解析得到用户所在省市区等.. 场景:商城类小程序,在首页时需展示附近门店,即用户刚进入小程序时就需要获取到用户位置信息 ste ...

  6. 微信小程序--缓存,支持过期时间的二次开发封装

    简介 微信小程序提供了缓存的api,包括同步和异步两种,具体api不多说明,可自行查看官方文档 现在微信小程序缓存api存在一个问题就是没有设定过期时间,下面给大家介绍一下对小程序缓存的二次封装,使其 ...

  7. 微信小程序四(设置底部导航)

    好了 小程序的头部标题 设置好了,我们来说说底部导航栏是如何实现的. 我们先来看个效果图 这里,我们添加了三个导航图标,因为我们有三个页面,微信小程序最多能加5个. 那他们是怎么出现怎么着色的呢?两步 ...

  8. 关于微信小程序登录,后端如何生成3rd_session?(后端为c#)

    各位大神,请教一个问题,现在是小程序端调用wx.login后,将code传入后端接口,后端发起微信服务器request获取openid和session_key,后端再自定义生成一个登录状态:3rd_s ...

  9. 微信小程序H5预览页面框架(二维码不隐藏)

    <!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content ...

随机推荐

  1. Mybatis下collections使用pageHelper进行分页

    pageHelper在对mybatis一对多分页时造成查询总页数结果不对的情况. 可以做出如下修改: service层: public CommonResult worksList(String us ...

  2. HDU 4612 Warm up (边双连通分量+缩点+树的直径)

    <题目链接> 题目大意:给出一个连通图,问你在这个连通图上加一条边,使该连通图的桥的数量最小,输出最少的桥的数量. 解题分析: 首先,通过Tarjan缩点,将该图缩成一颗树,树上的每个节点 ...

  3. 001.Linux开机启动过程

    相关Linux启动过程解析,此作为通用启动参考:

  4. Redis自学笔记:2.准备

    第2章:准备 '纸上得来终觉浅,绝知此事要躬行'--陆游 2.2启动和停止redis 表2-1 redis可执行文件说明 文件名 说明 redis- server redis服务器 redis-cli ...

  5. 2017-9-14-Linux移植:加快Linux主机的启动速度

    参考文章:http://www.mintos.org/skill/fast-boot.html 今天本来不打算写Blog了,Linux笔记本开机太慢了,浪费生命.何不干脆写一篇关于加快Linux主机启 ...

  6. tomcat环境变量详细配置步骤

    这篇文章主要为大家详细介绍了tomcat环境变量配置步骤,包括JDK环境变量配置,感兴趣的小伙伴们可以参考一下 本文实例为大家分享了tomcat环境变量的配置教程,供大家参考,具体内容如下 1.=== ...

  7. [Python]网络爬虫( 连载:大牛汪海 )

    汪海个人博客:http://blog.callmewhy.com/ Python爬虫专栏,汪海专栏 Python爬虫入门教程 简单的介绍如何使用Python的相关模块如urllib2来实现网络爬虫的基 ...

  8. Java爬取校内论坛新帖

    Java爬取校内论坛新帖 为了保持消息灵通,博主没事会上上校内论坛看看新帖,作为爬虫爱好者,博主萌生了写个爬虫自动下载的想法. 嗯,这次就选Java. 第三方库准备 Jsoup Jsoup是一款比较好 ...

  9. Java中Reflect的基本使用

    首先在package reflect下定义了一个类Book package reflect; class Book{ private String title; private double pric ...

  10. 深入理解JVM(5)——HotSpot垃圾收集器详解

    HotSpot虚拟机提供了多种垃圾收集器,每种收集器都有各自的特点,没有最好的垃圾收集器,只有最适合的垃圾收集器.根据新生代和老年代各自的特点,我们应该分别为它们选择不同的收集器,以提升垃圾回收效率. ...