javascript - 需要查找 JavaScript 数组中是否存在特定数字

Question

这个问题已经有答案了:

How do I check if an array includes a value in JavaScript? (62 个回答)

Best way to find if an item is in a JavaScript array? [duplicate] (8 个回答)

已关闭 3 年前。

我是 javascript 新手，下面的代码可能有一些返回错误。我想做的是在 JavaScript 数组中找到一个特定的数字。

const numberList = [1, 2, 3, 4];

function includes(arrays, searchElement) {
  for (let elements of arrays) {
    if (elements === searchElement) {
      return true;
    } else {
      return false;
    }
  }
}
console.log(includes(numberList, 3))

Answer 1

如果条件为false，则不应返回when。相反，您可以从循环外部返回 false:

const numberList = [1, 2, 3, 4];

function includes(arrays, searchElement) {
  for (let elements of arrays) {
    if (elements === searchElement) {
      return true;
    }
  }
  return false;
}
console.log(includes(numberList, 3))

尽管您可以使用内置 includes() 来实现相同的目的:

const numberList = [1, 2, 3, 4];
const IsExist = (numberList, search) => numberList.includes(search)? true : false;
console.log(IsExist(numberList, 3));