数组Array()

var a = [];//没有元素的数组
var b = [1,2,3];//有3个数值的数组

var a = 12;
var b = [7,a+1,a+2,a+3]

var c = [[1,{x:1,y:2}],[2,{x:4,y:5}]];

var a = new Array();//创建一个空数组
var b = new Array(3);//长度为3的数组
var c = new Array('red','mike','love');包含3个字符串值得数组

var a = [[1,2,3],4,5,6]

var arr = [1,2,3,4,5,6];
for(var i = 0; i<arr.length;i++){
  console.log(arr[i]);        
}
//输出
1
2
3
4
5
6

var arr = [1,2,3,4,5,6];
for(var i in arr){
  console.log(arr[i])  
}
//输出
1
2
3
4
5
6

var a = [1,2,3,4];
console.log(a.join('-'));
//输出1-2-3-4

var a = [1,2,3];
console.log(a.reverse());
//输出3,2,1
var a = ['x','y','z'];
console.log(a.reverse());
//输出z,y,x

var arr = ['z','x','y'];
console.log(arr.sort());
//输出x,y,z

var arr = [111,12,65,888,999,5];
alert(arr.sort(function(a,b){
    return a-b
}))
//输出5,12,65,111,888,999

var a = [1,2]
var b = [3];
console.log(a.concat(b));// [1,2,3]
console.log(a.concat(8));// [1,2,8]

var arr = [111,12,65,888,999,5]；
alert(arr.slice(2,3))//65
alert(arr.slice(2,4))//65,888

var a= [1,2,3,4,5,6];
alert(arr.splice(4));
//输出5,6
alert(arr.splice(1,2));
//输出2,3

var arr= ['a','bbb','ccc',1,2,1]
alert(arr.splice(1,1,'c','ccc'))；
//输出bbb
alert(arr);
//输出a,c,ccc,ccc,1,2,1

var arr= [1,2,3,4,5,6]
alert(arr.pop(2))
//输出6

var arr= [1,2,3,4,5,6]
alert(arr.push(2,2))
//输出8

var arr= []
alert(arr.unshift(1,2))
//输出2

var arr= ['a','bbb','ccc']
alert(arr.shift());
//输出a