JavaScript ऑब्जेक्ट की लेंथ कैसे प्राप्त करें?

उदाहरण

for...in लूप और hasOwnProperty() से ऑब्जेक्ट की प्रॉपर्टी काउंट करें।

var studentObject = new Object(); 
studentObject["studentFirstName"] = "John"; 
studentObject["studentLastName"] = "Doe"; 
studentObject["studentAge"] = 22; 
studentObject["studentCountryName"] = "US"; 
studentObject["studentCollegeName"] = "MIT"; 
studentObject["studentSubjectName"] = "JavaScript"; 
Object.findLength = function(stObject) { 
    var counter = 0, k; 
    for (k in stObject) { 
        if (stObject.hasOwnProperty(k)) counter++; 
    } 
    return counter; 
}; 
var lengthOfStudentObject = Object.findLength(studentObject); 
console.log("The length Student Object is=" + lengthOfStudentObject);

प्रोग्राम चलाने के लिए:

node fileName.js

आउटपुट

PS C:\Users\Amit\javascript-code> node demo191.js 
The length Student Object is=6