How to print object by id in an array of objects in JavaScript?
We have an array of objects and in every object, there is a key named id and whose value is a number.
Example:
const arr = [
{
'id' : 12,
'name' : 'Ram'
},
{
'id' : 32,
'name' : 'Shyam'
}
]
We want to find the value of the name property whose id number is n.
Example :
Input : 12 Output : Ram Input : 32 Output : Shyam
There are many approaches to solve this problem which are following
- Using Array.filter( )
- Using Array.find( )
- UsingLoops in JavaScript
Using Array.filter( ) Array.filter( ) method is used for creating a new array from an existing array after applying some conditions.
HTML
<!DOCTYPE html> <html> <body> <h1>Geeksforgeeks</h1> <p>Name of the id is : <span id="geeks"></span> </p> <script> // This is our array of Objects var data = [ { id: 1, name: "a" }, { id: 2, name: "b" }, { id: 3, name: "c" }, { id: 4, name: "d" }, { id: 5, name: "e" }, { id: 6, name: "f" }, ]; let idYouWant = 1; let propertyYouWant = "name"; // Using Array.filter( ) method // we are iterating through each // items in the array and // checking which item's // id value is equal to the id we want let res = data.filter((item) => { return item.id == idYouWant; }); // After using filter method we got an array // of object. Now take its first element and // use its 'propertyYouWant' key let exactRes = res[0][propertyYouWant]; // Printing the property we want document.getElementById("geeks").innerText = exactRes; </script> </body> </html> |
Output:
Using Array.find( ): Using Array.find( ) first we are searching in which object the given id exists, then we extract the name property from that object.
HTML
<!DOCTYPE html> <html> <body> <h1>Geeksforgeeks</h1> <p>Name of the id is : <span id="geeks"></span> </p> <script> // This is our array of Objects var data = [ { id: 1, name: "a" }, { id: 2, name: "b" }, { id: 3, name: "c" }, { id: 4, name: "d" }, { id: 5, name: "e" }, { id: 6, name: "f" }, ]; let idYouWant = 2; let propertyYouWant = "name"; // Using Array.find( ) we are searching // in which object our searching id present let res = data.find((item) => { return item.id == idYouWant; }); // Now print the property which you want from // the object res console.log(res[propertyYouWant]) document.getElementById("geeks").innerText = res[propertyYouWant]; </script> </body> </html> |
Output:
Using for loop Using for loop first we are iterating the array and searching in which object the given id present and after that, we are printing the property we wanted.
HTML
<!DOCTYPE html> <html> <body> <h1>Geeksforgeeks</h1> <p>Name of the id is : <span id="geeks"></span> </p> <script> // This is our array of objects var data = [ { id: 1, name: "a" }, { id: 2, name: "b" }, { id: 3, name: "c" }, { id: 4, name: "d" }, { id: 5, name: "e" }, { id: 6, name: "f" }, ]; let idYouWant = 4; let propertyYouWant = "name"; // Iterating over the array using for loop and // searching in which object the id present // After getting the object we print the // property we wanted from the object for (var i = 0; i < data.length; i++) { if (data[i].id == idYouWant) { // console.log(data[i][propertyYouWant]) document.getElementById("geeks").innerText = data[i][propertyYouWant]; } } </script> </body> </html> |
Output :
.png)
