functioncontains(arr, val){returnarr.filter((item)=>{returnitem == val }).length >0;} 方式三:array.indexOf array.indexOf此方法判断数组中是否存在某个值,如果存在返回数组元素的下标,否则返回-1。 [1, 2, 3].indexOf(1);//0["foo","fl...
// Function to check if an array contains a specific elementfunctioncontains(arr,element){// Iterate through the arrayfor(vari=0;i<arr.length;i++){// Check if the current element is equal to the target elementif(arr[i]===element){// Return true if the element is found in the array...
* needle is the item you are searching for * this is a special variable that refers to "this" instance of an Array. * returns true if needle is in the array, and false otherwise */ Array.prototype.contains =function( needle ) { for(iinthis) { if(this[i] == needle)returntrue; }...
我们可以将第一个数组转换为Set,然后遍历第二个数组的元素,判断Set中是否包含这些元素。 functioncontainsArray(array1,array2){constset=newSet(array1);for(leti=0;i<array2.length;i++){if(set.has(array2[i])){returntrue;}}returnfalse;}constarray1=[1,2,3,4,5];constarray2=[4,5,6,7,8];...
function contains(arr, val) { var i = arr.length; while (i--) { if (arr[i] === val){ return true; } } return false; } 1. 2. 3. 4. 5. 6. 7. 8. 9. 方式二:使用数组的some,filter等方法 使用some方法更简洁,一旦找到元素,迭代就会中止,从而避免了不必要的迭代周期。 ...
EN方法一：array.indexOf() 此方法判断数组中是否存在某个值，如果存在，则返回数组元素的下标，否则...
MS Ajax:array.indexOf(value) Ext:Ext.Array.contains(array, value) Lodash:_.includes(array, value, [from])(在4.0.0之前是_.contains) Ramda:R.includes(value, array) 请注意,一些框架将此实现为函数,而其他框架则将该函数添加到数组原型中。
prototype.contains = function ( needle ) { for (i in this) { if (this[i] == needle) return true; } return false; } Usage // Now you can do things like: var x = Array(); if (x.contains('foo')) { // do something special } Sponsored Ensure the availability of your data ...
falseifsearchValueis not found anywhere within the array Example 1: Using includes() method letlanguages = ["JavaScript","Java","C","C++"]; // checking whether the array contains 'C'letcheck1 = languages.includes("C"); console.log(check1);// true ...
③接着上述代码,typeof arr 和 arr instanceof Array 分别输出object和true。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 console.log(typeof(names));//objectconsole.log(namesinstanceofArray);//trueconsole.log(""instanceofString);//false 不是对象类型console.log(trueinstanceofBoolean);//false...