how to extract object name/ object properties

Question

Problem :

obj = {
 module1 : {type :'int' , value : 100 },
  module2 : {type :'str' , value : 'bio' }
  module3 : {type :'boolean' , value : 'true' }
}

how to print the object name/ object property

eg : expected string " module1 module2 module3"

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Answer 1

You can use Object.keys()

var array = Object.keys(obj);
var string = array.join(' ')

Demo: Fiddle

Note: May need to include the polyfill for older browsers

Answer 2

Duplicate question How to list the properties of a JavaScript object In modern browsers (IE9+, FF4+, Chrome5+, Opera12+, Safari5+) you can use the built in Object.keys method:

var obj = {
    module1 : {type :'int' , value : 100 },
    module2 : {type :'str' , value : 'bio' },
    module3 : {type :'boolean' , value : 'true' }
}
var keys = Object.keys(obj);

The above has a full polyfill but a simplified version is:

var getKeys = function(myobj){
   var keys = [];
   for(var key in myobj){
      keys.push(key);
   }
   return keys;
}

Alternatively replace var getKeys with Object.prototype.keys to allow you to call .keys() on any object. Extending the prototype has some side effects and I wouldn't recommend doing it.

Answer 3

Try this

for (var prop in obj) {
    obj[prop] = 'xxx';
 }