js的数组排序函数研究 sort(),reverse()

js 的数组排序函数研究 sort(),reverse()

js 的 sort()函数用来做数组排序非常有效且简单,以下是几种常用的场景.

<script>
var a = ['b','d','c','a','f','e'];
var b = a.sort();
console.log(b);
//b = ['a','b','c','d','e','f'];
</script>

当然,既然能以字典序排序,自然也能以大小排序.

<script>
var c = [9,4,5,2,3,1,8,7,6];
var d = a.sort(function(a,b){
    return a-b;
});
console.log(d);
//b = [1,2,3,4,5,6,7,8,9];
var e = a.sort(function(a,b){
    return b-a;
});
console.log(e);
//e = [9,8,7,6,5,4,3,2,1];
</script>

这就是天然的冒泡排序了,超级简单有木有?

reverse() 函数可以将数组倒序排列,通常我们可以用来倒序排列数据,可以缓解后端数据库的计算压力.

<script>
var a = ["s","g","a"];
console.log(a.reverse());
// ["a","g","s"];
</script>