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js常用數(shù)組操作方法簡明總結(jié)

 更新時(shí)間:2014年06月20日 09:22:19   投稿:junjie  
這篇文章主要介紹了js常用數(shù)組操作方法簡明總結(jié),直接上代碼,代碼中有詳細(xì)的注釋,需要的朋友可以參考下
//javascript 中的數(shù)組分割
var colors = ["red","green","blue"];
//alert(colors.toString());
alert(colors.join("|")); //返回結(jié)果是red|green|blue
var colors = ["red","green","blue",null];
alert(colors.join("|"));//red|green|blue|
//注意當(dāng)數(shù)組里面有值是null或者是undefined的時(shí)候 返回的結(jié)果是以空的字符串表示的
-------------------------------------------
//數(shù)組刪除和添加
var colors = ["red","green","blue"];
//alert(colors.toString());
colors.push("white","test");//返回的結(jié)果是數(shù)組的長度
alert(colors.join("|"));//結(jié)果是red|green|blue|white|test
//往數(shù)組的開頭添加元素
var colors = ["red","green","blue","test"];
var item = colors.unshift("first");//數(shù)組的開頭添加一個(gè)元素
alert(colors.join("|"));//返回最后的數(shù)組


//刪除元素
var colors = ["red","green","blue","test"];
var item = colors.pop();//返回刪除的選項(xiàng)結(jié)果test
alert(colors.join("|"));//返回最后的數(shù)組結(jié)果red|green|blue
//刪除開頭元素
var colors = ["red","green","blue","test"];
var item = colors.shift();//刪除數(shù)組的第一個(gè)選項(xiàng)
alert(colors.join("|"));//返回最后的數(shù)組
-------------------------------------------------
//數(shù)組順序事例
//順序顛倒
var colors = ["red","green","blue","test"];
colors.reverse();
alert(colors);//結(jié)果是:test,blue,green,red
//數(shù)組排序
var values = [0,1,5,10,7];
values.sort(compare);
alert(values);
//document.writeln(values);

}
 function compare(value1,value2){
	if(value1<value2){
		return 1 ;
	}else if(value1>value2){
		return -1 ;
	}else return 0 ;
} 
-----------------------------------------------------
//向數(shù)組中添加數(shù)組 concat()方法
var colors = ["color","red"];
var colors2 = colors.concat(["ccc","bbbb"],'3333',['vvccxx',['oolll','lll']]);
alert(colors2);//返回結(jié)果是:color,red,ccc,bbbb,3333,vvccxx,oolll,lll

//slice()方法復(fù)制數(shù)組中的元素并不會破壞之前的元素
var colors = ["color","red",'eeee','221111'];
var colors2 = colors.slice(1);//從1開始進(jìn)行復(fù)制
alert(colors2);//結(jié)果是:red,eeee,221111

var colors = ["color","red",'eeee','221111'];
var colors2 = colors.slice(1,3);//從1開始進(jìn)行復(fù)制到第3個(gè)位置結(jié)束
alert(colors2);//結(jié)果是red,eeee
---------------------------------------------------------------------
//數(shù)組中刪除元素
var a = [1,2,3,5,8];
var r = a.splice(0,2); //刪除前2項(xiàng)
alert(a);//結(jié)果是3,5,8

var a = [1,2,3,5,8];
var r = a.splice(1,1,100,200); //從第2個(gè)數(shù)開始刪除一項(xiàng) 然后插入100 200
alert(a);//結(jié)果是1,100,200,3,5,8

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