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{
a = 1;
}
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if(true)
{
var a = 1;
}
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var ob = function(){
var obj = this;
function fn1(){
alert( obj === window );//false
alert( this === window );//ture
}
this.fn2 = function() {
fn1();
}
}
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Dynamic Script Elements ¶¯Ì¬½Å±¾ÔªËØ
The Document Object Model (DOM) allows you to dynamically create almost any part of an HTML document using JavaScript. At its root, the <script> element isn't any different than any other element on a page: references can be retrie ......
XMLHttpRequest Script Injection XHR½Å±¾×¢Èë
Another approach to nonblocking scripts is to retrieve the JavaScript code using an XMLHttpRequest (XHR) object and then inject the script into the page. This technique involves creating an XHR object, downloading the JavaScript f ......