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How to print all the functions of JavaScript objects?

If I have var foo = 'bar';, how can I get all the functions called on foo, for example toUpperCase? This is not an object, therefore Object.getOwnPropertyNames (foo) does not work:

$ node
> var foo = 'bar';
undefined
> console.log(Object.getOwnPropertyNames(foo));
TypeError: Object.getOwnPropertyNames called on non-object
    at Function.getOwnPropertyNames (native)
    at repl:1:20
    at REPLServer.eval (repl.js:80:21)
    at repl.js:190:20
    at REPLServer.eval (repl.js:87:5)
    at Interface.<anonymous> (repl.js:182:12)
    at Interface.emit (events.js:67:17)
    at Interface._onLine (readline.js:162:10)
    at Interface._line (readline.js:426:8)
    at Interface._ttyWrite (readline.js:603:14)

katspaugh a simple, elegant solution :

> console.log(Object.getOwnPropertyNames(foo.constructor.prototype));
[ 'constructor',
  'length',
  'toLowerCase',
  ... ]
undefined
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3 answers

You want to use methods String.prototype, the prototype of all the lines, the Valindor line.

Object.getOwnPropertyNames('baz'.constructor.prototype)
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usage may use below:

$(document).ready(function () {
    var foo = 'bar';
    var div = '';
    var ob = Object.getOwnPropertyNames(foo.constructor.prototype);
    for (var i = 0; i < ob.length; i++) {
        div += ob[i] + "<br/>";
    }
    $(selector).html(div);
});
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