string to instance name in action script 3 - actionscript-3

Question

i'm having some problems with as3
var eventChildren:XMLList = eventInput.channel.children();
var nr:Number;
nr=0;
for each (var eventInfo:XML in eventChildren) {
nr++;
trace(eventInfo.title);
var ev="ev"+String(nr);
var titl="title"+String(nr);
trace(ev);
trace(titl);
var newEV:Object = Object(ev);
var newTITL:Object = Object(titl);
trace(newEV);
trace(newTITL);
newEV.newTITL.text=eventInfo.title;
}
}
this is my code, i'm trying to set the title value for every child instance of eventChild,
as i am new to action script in general, and action script 3 in particular i don't really know what i'm doing wrong here. I'm trying to set the text for ev1.title1, ev2.title2, etc. from values in eventChildren like this : first child, sets ev1.title1, second ev2.title2 and so on. Any ideas on what i should change in the code or where to look for some information ?
edit : thank you for the help, both answers took me to the right solution :
for each (var eventInfo:XML in eventChildren) {
nr++;
trace(eventInfo.title);
var ev="ev"+String(nr);
var titl="title"+String(nr);
//trace(ev);
//trace(titl);
var oTitle:Object = {}; // create object for the field titleXX
oTitle[titl] = {text:eventInfo.title}; // create and assign the field text to a new object
allFields[ev] = oTitle; // assign the title object to the field evXX
}
ev1.title1.text=allFields.ev1.title1.text;
ev2.title2.text=allFields.ev2.title2.text;
ev3.title3.text = allFields.ev3.title3.text;
ev4.title4.text=allFields.ev4.title4.text;

Answer 1

ev and titl are Strings and not Object, there is no eval in as3 so you will not be able to create a new variable based on a string name .But you can create a new Object that will have a field based on your ev string:
var o:Object={};
o[ev]="....";
So if ev is equal to the string "ev1" you will have an object with a field named ev1 => o.ev1=...
For the title you can do the same create a new Object that will have a field based on titl string:
var o:Object={};
o[titl]="...";
So if titl is equal to the string "title1" you will have an object with a field named title1 => o.title1=...
Same thing for the text you have to create an Object to hold the text field.
Mixing all this infos you end up with:
var eventChildren:XMLList = eventInput.channel.children();
var nr:Number=0;
var AllFields:Object={};
for each (var eventInfo:XML in eventChildren) {
nr++;
trace(eventInfo.title);
var ev="ev"+String(nr);
var titl="title"+String(nr);
trace(ev);
trace(titl);
var oTitle:Object = {}; // create object for the field titleXX
oTitle[titl] = {text:eventInfo.title}; // create and assign the field text to a new object
allFields[ev] = oTitle; // assign the title object to the field evXX
}
// then you can have access to all your field within the object allFields
trace(allFields.ev1.title1.text)
trace(allFields.ev2.title2.text)
See also this question for object notation

Answer 2

You can create the variable name using 'this':
this['mystring'] = new Object();
this.mystring.title = 'mytitle';
If you're doing this inside a class, the class has to be dynamic to allow for new members:
dynamic public class MyClass extends MovieClip {
public function MyClass() {
this['mystring'] = new Object();
this.mystring.title = 'mytitle';
}
}
If your class is not dynamic, you can still do this but must continue to use array notation rather than dot notation:
public class MyClass extends MovieClip { // not dynamic
public function MyClass() {
this['mystring'] = new Object();
this['mystring'].title = 'mytitle';
}
}