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function PoliceMan() {
//¶¨Òå³õʼÉúÃüÖµ
var lifeEnergy = 100;
//ÏÔʾµ±Ç°ÉúÃüÖµ
function showLifeEnergy() {
alert(lifeEnergy);
}
return showLifeEnergy;
}
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var pm = new PoliceMan();
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pm();
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function PoliceMan() {
//¶¨Òå³õʼÉúÃüÖµ
var lifeEnergy = 100;
//Öе¯¼õÉÙÉúÃüÖµ
InBullet = function(){
lifeEnergy -= 1;
}
//ÏÔʾµ±Ç°ÉúÃüÖµ
function showLifeEnergy() {
alert(lifeEnergy);
}
return showLifeEnergy;
}
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var pm = new PoliceMan();
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pm();
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InBullet();
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pm();
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Identifier Resolution Performance ±êʶ·ûʶ±ðÐÔÄÜ
Identifier resolution isn't free, as in fact no computer operation really is without some sort of performance overhead. The deeper into the execution context's scope chain an identifier exists, the slower it is to access for ......
Dynamic Scopes ¶¯Ì¬×÷ÓÃÓò
Both the with statement and the catch clause of a try-catch statement, as well as a function containing eval_r(), are all considered to be dynamic scopes. A dynamic scope is one that exists only through execution of code and therefore cannot be det ......
function db()
{
//»î¶¯±àºÅ
var activeid = Request.Form("activeid");
//Óû§Ãû
var username = Request.Form("username");
//ÊÖ»úºÅÂë
var mobile = Request.Form("mobile");
var conn= Server.CreateObject("ADODB.connection");
var rs= Serve ......