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JavaScript Program to Add Key/Value Pair to an Object
In this example, you will learn to write a JavaScript program that will add a key/value pair to an object.
To understand this example, you should have the knowledge of the following JavaScript programming topics:
Example 1: Add Key/Value Pair to an Object Using Dot Notation
// program to add a key/value pair to an object
const person = {
name: 'Monica',
age: 22,
gender: 'female'
}
// add a key/value pair
person.height = 5.4;
console.log(person);
Output
{
name: "Monica",
age: 22,
gender: "female",
height: 5.4
}
In the above example, we add the new property height to the person object using the dot notation . i.e. person.height = 5.4;.
Example 2: Add Key/Value Pair to an Object Using Square Bracket Notation
// program to add a key/value pair to an object
const person = {
name: 'Monica',
age: 22,
gender: 'female'
}
// add a key/value pair
person['height'] = 5.4;
console.log(person);
Output
{
name: "Monica",
age: 22,
gender: "female",
height: 5.4
}
In the above example, we add the new property height to the person object using the square bracket notation [] i.e. person['height'] = 5.4;.
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