//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.indexOf('Grapes'); // Find in String string...
Topic: JavaScript / jQueryPrev|NextAnswer: Use the indexOf() MethodYou 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 ...
check if an item exists in an array: const nums = [ 1, 3, 5, 7]; console.log(nums.includes(3)); // true
To check if a variable is an array in Javascript is essential to handle data appropriately. We will discuss three different approaches to check if a variable is an array or not. We are having an array and a string, and our task is to check if a variable is an array in JavaScript. ...
Vue.JS check if Array,Object or String is empty: In Vue.js, To check if an array is empty in Vue.js, you can use the Array.length property, which returns the number of elements in the array To check if the string is empty in Vue.js, you can use the
if (exists) { console.log("Yes"); // notify } 資料來源 Javascript: Check for an array of keywords match in a string https://stackoverflow.com/questions/54900214/javascript-check-for-an-array-of-keywords-match-in-a-string How to check if contains all keywords in any order of string?
Different methods to check if string contains spaces in JavaScript Method-1: UseindexOfmethod Not to be confused with the arrayindexOfmethod, theString.prototype.indexOf()takes a string argument and searches for it within the string it’s called upon and returns the index of the first occurren...
JavaScript offers many ways to check if a string contains a substring. Learn the canonical way, and also find out all the options you have, using plain JavaScript
The customisString()JavaScript function in the following example will returntrueif the variable is a string otherwise returnfalse. Let's try it out and see how it works: Example Try this code» // Defining a functionfunctionisString(myVar){return(typeofmyVar==='string');}// Sample variab...
In JavaScript, there are various methods available to check if a variable is undefined. Each method has its own use cases and subtle differences. 1. Using typeof Operator The typeof operator can be used to check if a variable is undefined by comparing its type with the string ‘undefined...