A tip when running javascript dynamically

约定不等于承诺〃 2022-08-25 02:20 17阅读 0赞

firefox works differently from ie when change src of a existing script , in ie this action cause the javascript engine to reload that script, and execute it ,while in firefox, nothing will happen

you can have your own test by following code

<
       
        script id
       
        =
       
        "
       
        s1
       
        "
       
         type
       
        =
       
        "
       
        text/javascript
       
        "
       
        >
       
        
    
       
        </
       
        script
       
        >
       
        
    
       
        <
       
        script language
       
        =
       
        "
       
        javascript
       
        "
       
         type
       
        =
       
        "
       
        text/javascript
       
        "
       
        >
       
        
        document
       
        .
       
        getElementById(
       
        "
       
        s1
       
        "
       
        )
       
        .
       
        src
       
        =
       
        "
       
        1.js
       
        "
       
        ;
    
       
        </
       
        script
       
        >

in 1.js we simply alert some message

alert("executed");

So if you want the browser to execute some js dynamically , you need to reload the script element. Add a script element into DOM will cause the execution of the script in both browser ,following code shows how to reload a script element

if
       
        (
       
        this
       
        .element)
    
       
        this
       
        .element.parentNode.removeChild(
       
        this
       
        .element);
    
       
        this
       
        .element
       
        =
       
        document.createElement(
       
        "
       
        SCRIPT
       
        "
       
        );
    
       
        this
       
        .element.type
       
        =
       
        "
       
        text/javascript
       
        "
       
        ;
    
       
        this
       
        .element.id 
       
        =
       
         
       
        "
       
        MzJsonElement
       
        "
       
        ;
    
       
        this
       
        .element.src
       
        =
       
        url;
    document.getElementsByTagName(
       
        "
       
        HEAD
       
        "
       
        )[
       
        0
       
        ].appendChild(
       
        this
       
        .element);

this might be helpful when we need our browser to run some json callback script