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This time I will bring you a summary of the three ways to dynamically load JS files. What are the precautions when using the three ways to dynamically load JS files. The following is a practical case, let's take a look.
1. Use the document.write/writeln() method
This method can realize the dynamic loading of js files. The principle is to re-load the js file. Write document flow, this method will cause the entire page to be redrawn.
document.writeln("<script src=\"http://lib.sinaapp.com/js/jquery/1.6/jquery.min.js\"></script>");
What needs to be noted is the escaping of special characters.
2. Use jQuery
Use getScript(url,callback) method to dynamically load js files
$.getScript('test.js',function(){ alert('done'); });
3. Use native js Method
Principle: Dynamically create a script tag and specify the src attribute of the script
function loadJs(url,callback){ var script=document.createElement('script'); script.type="text/javascript"; if(typeof(callback)!="undefined"){ if(script.readyState){ script.onreadystatechange=function(){ if(script.readyState == "loaded" || script.readyState == "complete"){ script.onreadystatechange=null; callback(); } } }else{ script.onload=function(){ callback(); } } } script.src=url; document.body.appendChild(script); } loadJs("test.js",function(){ alert('done'); });
You can also use the same principle to dynamically load css files, except that the inserted parent node is head Label.
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
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Detailed explanation of Vue.js calculation and use of listener properties
Loading jquery.js in JS Detailed explanation of method
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