Html5 implements QR code scanning and parsing _html5 tutorial skills

Introduction:
Recently there is a requirement for a company project. In the Weibo client, a button on the h5 page can interact with native to call up the camera, scan the QR code and parse it. In non-Weibo clients (WeChat or native browsers, such as Safari), call up the system's photo or upload picture button, and parse the QR code by taking a photo or uploading a picture.
The second solution requires parsing the QR code in front-end js. This relies on a third-party parsing library jsqrcode. This library already supports the operation of calling the camera on the browser side, but it relies on a property called getUserMedia. Mobile browsers do not support this attribute very well, so the QR code can only be parsed indirectly by uploading images.
GetUserMedia attribute compatible browser list:

First of all, I would like to thank the developer of jsqrcode for providing such an excellent code for parsing QR codes, which has reduced my workload a lot. jsqrcode address: Click me
My code library address: Click me
1. Problems solved:
1. Able to The Weibo client calls up the camera to scan the QR code and parse it;
2. Can scan the QR code and parse it in the native browser and WeChat client;
2. Advantages:
The web side or h5 side can directly complete the work of scanning the QR code;
3. Disadvantages:
The picture is not clear and it is easy to fail to parse (taking pictures to scan the picture requires the lens to be away from the QR code) (very close distance), there will be a 1-2 second delay compared to the native call camera analysis.
Note:
This plug-in needs to be used with zepto.js or jQuery.js
Instructions for use:
1. Where you need to use it The page imports the js files in the lib directory in the following order

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The code is as follows:

2. Customize the html style of the button
Because the plug-in needs to use , the html structure has a fixed display style on the web page. In order to customize the button style, we can nest the code according to the following sample code structure

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The code is as follows:

Scan QR code 1

Then set the css of the input button to hide the button, for example, I use the attribute Selector

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The code is as follows:

input[node-type=jsbridge ]{
visibility: hidden;
}

Here we only need to define the style of class="qr-btn" according to our own needs.
3. Initialize the Qrcode object on the page

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The code is as follows:

//Initialize the scan QR code button and pass in the custom node-type attribute
$(function() {
Qrcode.init($('[node-type= jsbridge]'));
});

Main code analysis

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The code is as follows:

(function($) {
var Qrcode = function(tempBtn) {
//This object only supports parsing under the Weibo domain, which means that it is not only for pages under the Weibo domain. The second solution can be used to parse the QR code
if (window.WeiboJSBridge) {
$(tempBtn).on('click', this.weiBoBridge);
} else {
$( tempBtn).on('change', this.getImgFile);
}
};
Qrcode.prototype = {
weiBoBridge: function() {
WeiboJSBridge.invoke('scanQRCode' , null, function(params) {
//Get the result of scanning the QR code
location.href=params.result;
});
},
getImgFile: function() {
var _this_ = this;
var imgFile = $(this)[0].files;
var oFile = imgFile[0];
var oFReader = new FileReader();
var rFilter = /^(?:image/bmp|image/cis-cod|image/gif|image/ief|image/jpeg|image/jpeg|image/jpeg|image/pipeg|image/png|image/svg xml|image /tiff|image/x-cmu-raster|image/x-cmx|image/x-icon|image/x-portable-anymap|image/x-portable-bitmap|image/x-portable-graymap|image/x -portable-pixmap|image/x-rgb|image/x-xbitmap|image/x-xpixmap|image/x-xwindowdump)$/i;
if (imgFile.length === 0) {
return;
}
if (!rFilter.test(oFile.type)) {
alert("Choose the correct image format!");
return;
}
/ /Code executed after successfully reading the image
oFReader.onload = function(oFREvent) {
qrcode.decode(oFREvent.target.result);
qrcode.callback = function(data) {
//Get the result of scanning the QR code
location.href = data;
};
};
oFReader.readAsDataURL(oFile);
},
destory: function() {
$(tempBtn).off('click');
}
};
//Initialization
Qrcode.init = function(tempBtn) {
var _this_ = this;
var inputDom;
tempBtn.each(function() {
new _this_($(this));
});
$('[node-type=qr-btn] ').on('click', function() {
$(this).find('[node-type=jsbridge]')[0].click();
});
};
window.Qrcode = Qrcode;
})(window.Zepto ? Zepto : jQuery);

Sample display
1. Call Previous page

2. The page after calling up