javascript - 需要从数组中删除字符串

Question

我在 for 循环中有一个数组，如下所示：

var arr = ["abc", "5", "city", "2", "area", "2", "max", "choice"];

我只需要这样的数字：

var arr = ["5","2","2"];

所以有人可以在这里帮忙。

Answer 1

另一种方法是使用转换后的数字到字符串并与原始值进行比较。

var array = ["abc", "5", "city", "2", "area", "2", "max", "choice"],
    result = array.filter(v => (+v).toString() === v);

console.log(result);

只是更短的方法isFinite

var array = ["abc", "5", "city", "2", "area", "2", "max", "choice"],
    result = array.filter(isFinite);

console.log(result);

使用underscore.js标记时，您可以使用下划线的过滤和回调。

var array = ["abc", "5", "city", "2", "area", "2", "max", "choice"],
    result = _.filter(array, _.isFinite);

console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"></script>

Answer 2

filter当它们被强制为一时，它们是整数的字符串：

var arr = ["abc", "5", "city", "2", "", "area", "2", "max", "choice"];

const out = arr.filter(el => (
  el !== '' && Number.isInteger(Number(el)))
);

console.log(out)

Answer 3

var arr = ["abc", "5", "city", "2", "area", "2", "max", "choice"];

const filtered = arr.filter(item => !isNaN(item));

console.log(filtered);

Answer 4

您可以将filter方法与isNaN功能一起使用var numbers = arr.filter(c=> !isNaN(c));

var arr = ["abc", "5", "city", "2", "area", "2", "max", "choice"];
var numbers = arr.filter(c=> !isNaN(c));
console.log(numbers);

Answer 5

使用forEach循环和检查使用isNaN()

var arr = ["abc", "5", "city", "2", "area", "2", "max"];
var a=[];
arr.forEach(e=>isNaN(e)?true:a.push(e))
console.log(a)