Javascript总结

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DocumentFragment：文档碎片，它不会产生任何标签，只是一个载体:

var df = document.createDocumentFragment();
for(var i=0;i<5;i++){
var bullet = new Bullet();
df.appendChild(bullet);

}

document.body.appendChild(df);

javascript hijacking:(http://blog.csdn.net/farcall/archive/2011/02/06/6173139.aspx)

<script type="text/javascript">

</script>
<html>
<body>
<input type="button" onclick="javascript: alert('Hello World!')" value="test" />
</body>
</html>

//回调函数1    
function callback(a,b,c)   
{    
  alert(a+b+c);   
}    
//回调函数2    
function callback2(a,b)   
{    
  alert(a+b);   
}    
//这个方法做了一些操作、然后调用回调函数   
function doCallback(fn,args)   
{    
    fn.apply(this, args); 
}    
    
function test()   
{    
        
    //动态调用方法、并传递参数   
  doCallback(eval("callback2"),['a','b']);   
  doCallback(callback,['a','b','c']);   
}

使用 eval("callback2")可以实际动态调用

定义JavaScript注册事件:

1.
var obj1 = document.getElementById("obj1");
if ($.browser.msie) {
//IE内核浏览器的注册方式
focus.attachEvent("ActiveScreenChanged",listener_ActiveScreen);
} else {
//非IE内核浏览器注册方式
//当然这里其实没有必要，因为只有IE内核浏览器才能执行此处讨论的COM组件
focus.addEventListener("ActiveScreenChanged",listener_ActiveScreen);
}

function listener_ActiveScreen(playerIndex) {
$('#currentWin').html('播放窗口:' + playerIndex);
//TODO
}

3.如何响应ActiveX对象返回的对象事件

(A second script block that defines your event handler based on the global variable. This has to be a separate script block, and the object has to be defined before this script block evaluates. Syntax is "function object::Event(params)", where "object" is the name of the variable containing the object, "Event" is the name of the even to which you're subscribing, and "params" is the set of parameters the event handler expects.)