//http://www.jermywells.com //js encapsulation var Person = function (n,o,g,a) { //private variables var name = n || ''; var occupation = o || ''; var gender = g || ''; var age = a || ''; this.toString = function(){ return JSON.stringify({ name:name, occupation:occupation, gender:gender, age:age }); } } var Gender = { male: 'male', female: 'female' } var jeremy = new Person( 'Jeremy Wells', 'Programmer', Gender.male, 35 ); document.body.innerHTML = jeremy.toString();