每天一個JavaScript執行個體-使用帶有定時器的函數閉包，javascript定時器
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閉包的簡單概念:
閉包就是能夠讀取其他函數內部變數的函數。
函數內部的函數閉包的兩個最大的作用
讀取函數內部的變數
變數的值始終保持在記憶體中
function A()
{
var n=999;
nAdd=function(){n+=1}
function B()
{
alert(n);
}
return B;
}
var result=A();
result(); // 999
nAdd();
result(); // 1000
javascript的閉包與變數
return function(){
return num;
};
這一個方法呢是可以訪問到的。
function(num){```````}(i);
這個嘛，記住就行了。
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