JavaScript: Find the length of an object

Last update on May 30 2022 09:59:16 (UTC/GMT +8 hours)

JavaScript Object: Exercise-3 with Solution

Write a JavaScript program to get the length of a JavaScript object.

Sample object:
var student = {
name : "David Rayy",
sclass : "VI",
rollno : 12 };

Sample Solution: -

HTML Code:

<!DOCTYPE html>
  <html>
  <head>
  <meta charset="utf-8">
  <title>Write a JavaScript program to get the length of a JavaScript object.</title>
  </head>
  <body>
 </body>
  </html>

JavaScript Code:

//Write a JavaScript program to get the length of a JavaScript object.

Object.objsize = function(Myobj) {
    var osize = 0, key;
    for (key in Myobj) {
        if (Myobj.hasOwnProperty(key)) osize++;
    }
    return osize;
};

var student = { 
name : "David Rayy", 
sclass : "VI", 
rollno : 12 };

var objsize = Object.objsize(student);
console.log('Size of the current object : '+objsize);

Sample Output:

Size of the current object : 3

Flowchart:

Live Demo:

See the Pen javascript-object-exercise-3 by w3resource (@w3resource) on CodePen.

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JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); arr.splice(2, 0, "Lene"); console.log(arr.join());

Ref: https://bit.ly/2BXbp04