JavaScript_ÅжÏÍøÂçͼƬÊÇ·ñ´æÔÚ
//̽²âͼƬÊÇ·ñ´æÔÚ
function IsExist(url)
{
x = new ActiveXObject("Microsoft.XMLHTTP")
x.open("HEAD",url,false)
x.send()
return x.status==200
}
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function wu()
{
var w=new object;
o.a=1;
return o;
}ÓÃÕâÖÖ·½Ê½´´½¨¶ÔÏó£ºvar u=wu();
2¡¢´´½¨¹¹Ô캯Êý£¬ÓÃnewʵÀý»¯ÀýÈ磺
function wu()
{this.a=1;}
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Definition and Usage
¶¨ÒåÓëÓ÷¨The constructor property is a reference to the function that created an object.
constructorÊôÐÔÊÇËù½¨Á¢¶ÔÏóµÄº¯Êý²Î¿¼Syntax
Óï·¨object.constructor
Example 1
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In this example we will show how to use the constructor property:
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eg:
<HTML>
<script language="JavaScript">
//VBScript,Jscript,ECMAScript
<!--
alert(n ......
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<link href="css/main0.css" rel="stylesheet" type="text/css" id="cssfile" />
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