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1 Object.prototype.Property = 1;
Object.prototype.Method = function ()
{
    alert(1);
}
 
var obj = new Object();
alert(obj.Property);
obj.Method();
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JSÖÐÔÊÐíµÄÀàÐÍÓÐArray, Boolean, Date, Enumerator, Error, Function, Number, Object, RegExp, String
2 var obj = new Object();
obj.prototype.Property = 1; //Error
//Error
obj.prototype.Method = function()
{
    alert(1);
}
ÔÚʵÀýÉϲ»ÄÜʹÓÃprototype£¬·ñÔò·¢Éú±àÒë´íÎó
3 Object.Property = 1;
Object.Method = function()
{
    alert(1);
}
 
alert(Object.Property);
Object.Method();
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4 Object.Property = 1;
Object.Method = function()
{
    alert(1);
}
var obj = new Object();
alert(obj.Property); //Error
obj.Method(); //Error
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5 function Aclass()
{
this.Property = 1;
this.Method = function()
{
    alert(1);
}
}
var obj = new Aclass();
alert(obj.Property);
obj.Method();
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6 function Aclass()
{
this.Property = 1;
this.Method = function()
{
    alert(1);
}
}
Aclass.prototype.Property2 = 2;
Aclass.prototype.Method2 = function
{
    alert(2);
}
var obj = new Aclass();
alert(obj.Property2);
obj.Method2();
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Regular Expression Optimization  ÕýÔò±í´ïʽÓÅ»¯
    Incautiously crafted regexes can be a major performance bottleneck (the upcoming section, "Runaway Backtracking" on page 91, contains several examples showing how severe this can be), but there is a lot you can do to improve re ......

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<script>
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function isNumeric(strNumber) {
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<script>
 //¼ì²éÊÇ·ñΪÈÎÒâÊý£¨ÊµÊý£©
function isNumeric(strNumber) {
var newPar=/^(-|\+)?\d+(\.\d+)?$/
alert(newPar.test(strNumber)); }
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