Check If Object Value Exists and Not Add New Object to Array in JavaScript

In this article, you will understand how to check if the object value exists, if not, add a new object to the array using JavaScript. In Javascript, almost every variable is an object. An object can be a string, numbers, boolean values, etc. They can also be key-value pairs.

An array in javascript is a special variable that can hold more than one item. An array can be initialized using the keyword ?const'.

Example 1

In this example, we check the existence of the object using the .some() function.

var inputArray = [{ id: 1, name: "JavaScript" },
   { id: 2, name: "javascript"},
   { id: 3, name: "Scala" },
   { id: 4, name: "Java" }]
console.log("The input array is defined as: ")
console.log(inputArray)
function checkName(name) {
   return inputArray.some(function(check) {
      return check.name === name;
   });
}
console.log("Does the object JavaScript exist in the array? ")
console.log(checkName('JavaScript'));
console.log("
Does the object HTML exist in the array? ")
console.log(checkName('HTML'));

Explanation

• Step 1 ?Define an array ?inputArray' and add key value pair values to it.

• Step 2 ?Define a function ?checkName' that takes a string as a parameter.

• Step 3 ?In the function, use the function some() to check if the given value exists in the array.

• Step 4 ?Display the boolean value as result.

Example 2

In this example, we add the object value to the array by pushing the object at the end of the array using push() function.

var inputArray = [{ id: 1, name: "JavaScript" },
{ id: 2, name: "javascript"},
{ id: 3, name: "Scala" }]
console.log("The input array is defined as: ")
console.log(inputArray)
function addObject(name) {
   inputArray.push({ id: inputArray.length + 1, name: name });
   return true;
}
console.log("Adding Object : Java to the array")
addObject("Java")
console.log("The array after adding the object is")
console.log(inputArray)

Explanation

• Step 1 ?Define an array ?inputArray' and add key value pair values to it.

• Step 2 ?Define a function ?addObject' that takes a string as a parameter.

• Step 3 ?In the function, use the function array.push to push the object to the last position of the array.

• Step 4 ?Display the array as result.