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ÇóÖµº¯Êýeval()
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1¡¢eval()º¯Êý
ÇóÖµº¯Êýeval()µÄ¸ñʽΪ£ºeval(<±í´ïʽ>)
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<script>
function show(obj)
{
var str=eval("document.Form."+obj+".value");
alert(“ÄãÊäÈëµÄÐÕÃûÊÇ:”+str);
}
</script>
<form name="Form" id="Form">
ÐÕÃû£º
<input name="name" type="text" value="ΤС±¦">
<input name="button" type="button" value="Ìá½»" onClick=show("name")>
</form>
2¡¢isNaN()º¯Êý
ÊýÖµÅжϺ¯ÊýisNaN()µÄ¸ñʽ£ºisNaN(<Á¿>)
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<script>
var x=15;
var y="»ÆÑÅÁá";
document.write("<LI>x²»ÊÇÊýÖµÂð£¿",isNaN(x));
document.write("<LI>y²»ÊÇÊýÖµÂð£¿",isNaN(y));
</script>
3¡¢parseInt()º¯Êý
ÕûÊýת»»º¯ÊýparseInt()µÄ¹¦ÄÜÊǽ«²»Í¬½øÖÆ£¨¶þ¡¢°Ë¡¢Ê®Áù£©µÄÊýֵת»»³ÉÊ®½øÖÆÕûÊý¡£
¸ñʽ£ºparseInt(ÊýÖµ×Ö´®[£¬µ×Êý])
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<script>
document.write("1101<sub>2</sub>=",parseInt("1101",2),"<sub>10</sub><br>");
document.write("BFFF<sub>16</sub>=",parseInt("BFFF",16),"<sub>10</sub><br>");
</script>
4¡¢parseFloat()º¯Êý
parseFloat()ÊǸ¡µãÊý
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prototype ÊÇÔÚ IE 4 ¼°ÆäÒÔºó°æ±¾ÒýÈëµÄÒ»¸öÕë¶ÔÓÚijһÀàµÄ¶ÔÏóµÄ·½·¨£¬¶øÇÒÌØÊâµÄµØ·½±ãÔÚÓÚ£ºËüÊÇÒ»¸ö¸øÀàµÄ¶ÔÏóÌí¼Ó·½·¨µÄ·½·¨£¡ÕâÒ»µã¿ÉÄÜÌýÆðÀ´»áÓеãÂÒ£¬±ð¼±£¬ÏÂÃæÎÒ±ãͨ¹ýʵÀý¶ÔÕâÒ»ÌØÊâµÄ·½·¨×÷ÒÑϽ²½â£º
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stringObject.charAt(index)·½·¨£º·µ»ØÖ¸¶¨Ë÷ÒýλÖô¦µÄ×Ö·û¡£
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function checkImgAddr(url){
var xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
xmlhttp.open("post",url,false);
xmlhttp.send();
if(xmlhttp.readyState==4){
if(xmlhttp.status==404){
return "File Not Exist.";
}else if(xmlhttp.status == 200){
re ......
String.prototype.HTMLEncode = function() {
var temp = document.createElement ("div");
(temp.textContent != null) ? (temp.textContent = this) : (temp.innerText = this);
var output = temp.innerHTML;
temp = null;
return output;
}
String.prototype.HTMLDecode = function() {
var temp = doc ......