check if an item exists in an array: const nums = [ 1, 3, 5, 7]; console.log(nums.includes(3)); // true
示例2: 在这个示例中,使用if-else语句来确定数组中是否存在’cat’。如果在数组中找到’cat’,则会在控制台上打印消息“Cat is in the array!”。如果在数组中找不到’cat’,则会打印消息“Cat is not in the array.”。JavaScriptconst animals = ['dog', 'cat', 'bird', 'rabbit']; // Check if...
put-array-or-string-here.indexOf() Code //code to check if a value exists in an array using javascript indexOf var fruits_arr = ['Apple', 'Mango', 'Grapes', 'Orange', 'Fig', 'Cherry']; var string = "Orange"; // Find in Array fruits_arr.indexOf('Tomato'); fruits_arr.index...
jQuery.inArray( value, array ) 搜索数组中指定值并返回它的索引(如果没有找到则返回-1)。 value要搜索的值。 array一个数组,通过它来搜索。 当然,处于学习,自己也去写了这样的函数: 代码如下: function inArray1(needle,array,bool){ if(typeof needle=="string"||typeof needle=="number"){ for(var ...
To check if a variable is an array in JavaScript, we have used isArray() method. It returns a boolean value as result, either true or false. We have used two div elements to display the array and output using getElementById() and innerHTML property. We have also added a button which...
You can use the indexOf() method to check whether a given value or element exists in an array or not. The indexOf() method returns the index of the element inside the array if it is found, and returns -1 if it not found. Let's take a look at the following example:...
function isObject(val) {returnval&& typeofval==='object'&& !Array.isArray(val);} 8. Empty 当if (obj) 无法满足需求时。 functionisEmpty(obj) {returnObject.keys(obj).length===0;} 9. UUID 生成器 即时唯一 ID——无需...
2个自定义的PHP in_array 函数,解决大量数据判断in_array的效率问题 大家可能都用过in_array来判断一个数据是否在一个数组中,一般我们的数组可能数据都比较小,对性能没什么影响,所以也就不会太在意 上传者:weixin_38608379时间:2020-10-26 php数组函数序列之in_array() – 查找数组中是否存在指定值 ...
functionisFruit(fruitName){letfruits=['Apple','Mango','Pear','Peach'];if(fruits.indexOf(fruitName)>-1){returntrue;}else{returnfalse;}}isFruit('Pear');isFruit('Cat'); Output: truefalse Using the.includes()Function to Check if Array Contains Value in JavaScript ...
We can also use thefind()method to check if an array includes a value. This method returns the first element in the array that satisfies the provided testing function. letfruits=["apple","banana","orange"];lethasBanana=fruits.find(fruit=>fruit==="banana");console.log(hasBanana);// "ba...