//code to check if a value exists in an array using javascript for loop var fruits_arr = ['Apple', 'Mango', 'Grapes', 'Orange', 'Fig', 'Cherry']; function checkValue(value, arr) { var status = 'Not exist'; for (var i = 0; i < arr.length; i++) { var name = arr[...
const checkKey = (obj, keyName) => { let keyExist = Object.keys(obj).some(key => key === keyName); console.log(keyExist); }; checkKey(user, 'name'); // Return true Using some() for an Array let number = [12, 33, 14, 45]; // Check if key exists number.some(value...
If you attempt to access a property that doesn’t exist on an object, it will return undefined. This is an example of the code. const person = { name: "John" }; console.log(person.age); // undefined 4. Array Indices If you try to access an element of an array that hasn’t b...
// function return if an element is found in the array, else falsefunctioncheckTrueExistsArray(array) {for(vark=0;k<array.length;k++) {if(array[k]) {returntrue;break;}}returnfalse;}vararrayVariable=[false,false,true,false,true];vararrayVariable1=[false,false,false,false,false];console....
If we were to check for a value that does not exist in the array, such as “grape”, the method would return -1. let fruits = ["apple", "banana", "orange"]; let index = fruits.indexOf("grape"); console.log(index); // -1 Another method for checking if an array includes a ...
<?php$search_array=array('first'=>1,'second'=>2);if(array_key_exists('first',$search_array)){echo"The 'first' element is found in the array";}else{echo"Key does not exist";}?> Output: The 'first' element is found in the array ...
In each iteration, use Array.prototype.indexOf() (or Array.prototype.includes()) to check if the current element of first array exists in the second array; Return true from the callback if all elements of first array exist in the second array, otherwise, return false. For exampl...
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In this example, we're checking if eachdivelement exists in the DOM. If the element exists, it logs "Element exists" to the console, otherwise, it logs "Element does not exist". Checking for Specific Element Types We can also check if specific types of elements exist. For instance, if...
Here, we will see how to check if a given key exists as a key-value pair inside a JavaScript Object? We will first see how it is done and then see a practical use case where you need to check if a certain key exists in a JavaScript Object?