JavaScript: List the properties of a JavaScript object

JavaScript Object: Exercise-1 with Solution

List Object Properties

Write a JavaScript program to list the properties of a JavaScript object.
Sample object:
var student = {
name : "David Rayy",
sclass : "VI",
rollno : 12 };
Sample Output: name,sclass,rollno

Sample Solution:

JavaScript Code:

function _keys(obj) 
 {
    if (!isObject(obj)) return [];
    if (Object.keys) return Object.keys(obj);
    var keys = [];
    for (var key in obj) if (_.has(obj, key)) keys.push(key);
    return keys;
  }
function isObject(obj) 
{
    var type = typeof obj;
    return type === 'function' || type === 'object' && !!obj;
  }
console.log(_keys({red: "#FF0000", green: "#00FF00", white: "#FFFFFF"}));

Output:

["red","green","white"]

Flowchart:

Live Demo:

See the Pen javascript-object-exercise-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that lists all own properties of an object using Object.keys().
• Write a JavaScript function that retrieves both enumerable and non-enumerable property names of an object.
• Write a JavaScript function that recursively traverses an object to list properties of nested objects.
• Write a JavaScript function that prints each property name along with its data type from a given object.

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