1.多维数组变成一维数组的俩种方法
方法一、apply结合concat拉平数组
var arrs=[[3,4,5,6,7],[67,45,23,45,12,20],[4,5,9,12,18],67,72,10]
console.log([].concat.apply([],arrs))
结果:[3, 4, 5, 6, 7, 67, 45, 23, 45, 12, 20, 4, 5, 9, 12, 18, 67, 72, 10]
方法二,ES6的一种方法(ES6新增数组扩展 flat())
var arrs=[[3,4,5,6,7,98],[6,2,3,5,8,],34,43]
console.log(arrs.flat(Infinity))
结果:[3, 4, 5, 6, 7, 98, 6, 2, 3, 5, 8, 34, 43]
2.数组排序的方法
先封装一个方法
function posts(v1,v2){
if(v1<v2){
return -1
}else if(v1>v2){
return 1
}else{
return 0
}
}
var arrays=[23,34,55,6,78,34,67,34,789,356,456,98]
arrays.sort(posts)
console.log(arrays)
结果:[6, 23, 34, 34, 34, 55, 67, 78, 98, 356, 456, 789]