Retrieving the string value of a javascript object entry

Question

Say I have an object which is as follows:

var myObj = {FOO: 0, BAR: 1};

How can I get the string value of one of the keys?

If I do a:

console.log(myObj.FOO);

It will print 0 whereas I want to print 'FOO'.

How can this be achieved?

Answer 1

to display the property names, you can loop through them:

for (name in obj) {
  alert("This is the key: " + name);
  alert("This is the value: " + obj[name]);
}

Answer 2

You can use the Object.keys() method. The following returns "FOO":

Object.keys(myObj)[0];

For more on Object.keys():

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys

Answer 3

You can log object property names through a loop.

var myObj = { FOO : 0, BAR : 1 };

for( var propertyName in myObj ) {

    console.log( propertyName );

}

Or you can retrieve object property names on a 0 indexed array using Object.getOwnPropertyNames.

var myObj = { FOO : 0, BAR : 1 };

var propertyNames = Object.getOwnPropertyNames( myObj );

console.log( propertyNames[ 0 ] ); //This shold log "FOO"

Or you can achieve the same result as above using Object.keys.

var myObj = { FOO : 0, BAR : 1 };

var propertyNames = Object.keys( myObj );

console.log( propertyNames[ 0 ] ); //This shold log "FOO"