JS快速建立一個數組,長度100,值是下標或者0
阿新 • • 發佈:2021-12-14
JS快速建立一個數組,長度100,值是下標或者0
1.Object.keys和Array.apply和map
var arr = Object.keys(Array.apply(null, { length: 100 })).map(function( item ) { return +item; });
2.Object.keys和Array.from和map
var arr = Object.keys(Array.from({ length: 100 })).map(function(item) { return +item; });
3.擴充套件運算子和Array.from
var arr=[...Array.from({ length: 100 }).keys()]
4.擴充套件運算子和Array.apply
var arr=[...Array.apply({ length: 100 }).keys()]
5.擴充套件運算子和new Array()
var arr = [...new Array(100).keys()];
6.擴充套件運算子和Array()
var arr = [...Array(100).keys()];
7.Array.from =>k
var arr = Array.from({ length: 100 }, (v, k) => k);// 值為0 var arr = Array.from({ length: 100 }, ()=>0);
8.遞迴呼叫
var s = []; var i =0; function array(num){ if(i<100){ s[i] = i++ array(num); } return s; } console.log(array(100));
值為0
1.var arr = new Array(100).fill(0); 2.var arr = [...Array(100).fill(0)]; 3.var arr = new Array(101).join(0).split("").map(item => {return +item; }); 4. var arr = new Array(100);arr = arr.map(item=>0); 5. Array.apply(null, { length: 100 }).fill(0);