javascript "new" function

[gongpex]

hello everyone,I had tried to create object inside object like this script using "new" function

<script language="javascript">  function person(name, age, gender)   {   this.name=name;   this.age=age;   this.gender=gender;   }  function car(factory, model, year, owner)   {   this.factory=factory;   this.model=model;   this.year=year;   this.owner=owner;   }    lany= new person("lany",15,"female");  andy= new person("Andy",40,"male");  henry= new person("Henry",35,"male");  tiny= new person("Tiny",55,"female");    car_me=new car("toyota","corolla",1996,"lany");  car_dad=new car("nissan","pulsar",1994,"andy");  car_uncle=new car("daihatsu","charade",1992,"henry");  car_aunt=new car("honda","civic",1990,"tiny");    document.write("my car is=" , car_me.owner.age);    </script>

but the results is "undefined" what's mistake of this script?and what the function of "this." in javascript?please someone tell to methanks

[radish]

The purpose of "this." is to differentiate that objects variables from other variables in the script.it basically is telling the browser"this variable is inside this object use it."this quote is lifted from the w3c tutorial on objects. http://www.w3schools.com/js/js_objects.asp

Inside the function you need to assign things to this.propertyName. The reason for all the "this" stuff is that you're going to have more than one person at a time (which person you're dealing with must be clear). That's what "this" is: the instance of the object at hand.

  lany= new person("lany",15,"female");  andy= new person("Andy",40,"male");  henry= new person("Henry",35,"male");  tiny= new person("Tiny",55,"female");    car_me=new car("toyota","corolla",1996,"lany");  car_dad=new car("nissan","pulsar",1994,"andy");  car_uncle=new car("daihatsu","charade",1992,"henry");  car_aunt=new car("honda","civic",1990,"tiny");

also you need to insert a var in front of your object variables to tell javascript that you are creating a new variable in that scope. otherwise it tries to look for a global variable.like this

var lany= new person("lany",15,"female");

[Ingolme]

The problem is that you're passing a string as the owner, rather than the variable refering to the owner object. lany= new person("lany",15,"female"); car_me=new car("toyota","corolla",1996,lany); // This is not quoted because it's not a string

[gongpex]

The problem is that you're passing a string as the owner, rather than the variable refering to the owner object. lany= new person("lany",15,"female"); car_me=new car("toyota","corolla",1996,lany); // This is not quoted because it's not a string

Yeah, you right thank you for answer