在JavaScript中,array.find()是一个数组方法,用于在数组中查找满足指定条件的第一个元素,并返回该元素。如果找到匹配的元素,则返回该元素;否则返回undefined。 array.find()方法接受一个回调函数作为参数,该回调函数可以接受三个参数:当前元素、当前索引和原始数组。回调函数应返回一个布尔值,用于判断当前元素是否满足...
document.getElementById("demo").innerHTML= ages.find(checkAge); } Try it Yourself » Description Thefind()method returns the value of the first element that passes a test. Thefind()method executes a function for each array element.
The find() method returns the value of the first element in an array that pass a test (provided as a function).The find() method executes the function once for each element present in the array:If it finds an array element where the function returns a true value, find() returns the ...
The findIndex() method returns the index of the first element in an array that pass a test (provided as a function).The findIndex() method executes the function once for each element present in the array:If it finds an array element where the function returns a true value, findIndex()...
JavaScript 中文开发手册 array.find (Array) - JavaScript 中文开发手册 find() 方法返回数组中满足提供的测试函数的第一个元素的值。否则返回undefined。 1 2 3 4 5 functionisBigEnough(element) { returnelement >= 15; } [12, 5, 8, 130, 44].find(isBigEnough);// 130 ...
The Reactjs Array find() method is a built-in function used to search and retrieve elements from an array that meet certain conditions. It takes a callback function as an argument and returns the first element that satisfies the provided condition. For i
❮PreviousJavaScript ArrayReferenceNext❯ Example 1 Find the first element with a value over 18: constages = [3,10,18,20]; ages.findIndex(checkAge); functioncheckAge(age) { returnage >18; } Try it Yourself » Description ThefindIndex()method executes a function for each array element...
简单地说,find不期望返回承诺,因为它不适用于异步事物。它循环遍历数组,直到其中一个元素导致返回真值。一个对象,包括一个 promise 对象,是真实的,所以查找在第一个元素上停止。 如果您想要一个与 find 等效的异步方法,则需要自己编写。您需要考虑的一个因素是您是想并行运行,还是想按顺序运行,在移动到下一个索引...
如果您需要兼容不支持Object.defineProperty的JavaScript引擎,那么最好不要对Array.prototype方法进行 polyfill ,因为您无法使其成为不可枚举的。 规范 Specification Status Comment ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'Array.prototype.find' in that specification. ...
代码语言:javascript 代码运行次数:0 运行 AI代码解释 function isPrime(element, index, array) { var start = 2; while (start <= Math.sqrt(element)) { if (element % start++ < 1) { return false; } } return element > 1; } console.log([4, 6, 8, 12].find(isPrime)); // undefined ...