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JavaScript

brandonlind2
brandonlind2
7,823 Points
Posted by brandonlind2
brandonlind2
7,823 Points

how can I pass object properties, to in a argument of a object created with a constructor function?

I'm attempting to a create a simple text based video game as practice project. The last line of code isnt working, how could I modify this code to get it to work? sorry i cant get the code to highlight correctly

//ammo
function Ammo(damage,name){
    this.damage=damage;
    this.name=name;} 
var ammo={
    556: new Ammo(30,'5.56'),
    308: new Ammo(80,'.308'),
    ninemm: new Ammo(30,'9mm'),
    45: new Ammo(80,'45acp'),
    762: new Ammo(50,'7.62x39'),
    22: new Ammo(10,'.22')}
//weapons
function RangedWeapon(accuracy,damage,speed,ammo){
    this.accuracy=accuracy;
    this.damage=damage;
    this.speed=speed;
    this.attachments= []; 
        this.upgrades= [];}
RangedWeapon.prototype.attachmentAdd= function(attachment){ 
        this.attachments.push(attachment);}
RangedWeapon.prototype.upgrades= function(upgrade){
    this.upgrades.push(upgrade);}
var RangedWeapons= {
    ar15: new RangedWeapon(80,ammo.556.damage,50,ammo.556)
        };

2 Answers

Julie Myers
Julie Myers
7,627 Points
Julie Myers
Julie Myers
7,627 Points

I messed around with you code and what I found is the only key I could get to in the ammo object is ninemm. I got the following error when I tried to reach the keys that start with a number: "Uncaught SyntaxError: Unexpected number(…)"

If you look at javaScript variable rules they can not start with a number. That rules seems to apply for object key names as well. If you change all the ammo object key's to start with a letter that should solve your issue.

This is how I redid your coding:

function Ammo(damage,name){
    this.damage=damage;
    this.name=name;
}

var ammo={
    five56: new Ammo(30,'5.56'),
    three08: new Ammo(80,'.308'),
    ninemm: new Ammo(30,'9mm'),
    four5: new Ammo(80,'45acp'),
    seven62: new Ammo(50,'7.62x39'),
    twenty2: new Ammo(10,'.22')
}

//weapons
function RangedWeapon(accuracy,damage,speed,ammo){
    this.accuracy=accuracy;
    this.damage=damage;
    this.speed=speed;
    this.attachments= []; 
        this.upgrades= [];
}

RangedWeapon.prototype.attachmentAdd= function(attachment){ 
        this.attachments.push(attachment);
}

RangedWeapon.prototype.upgrades= function(upgrade){
    this.upgrades.push(upgrade);
}

var RangedWeapons= {
    ar15: new RangedWeapon(80,ammo.five56.damage,50,ammo.five56)
};

By the way I hadn't thought of calling a constructor function from inside of an object.

brandonlind2
brandonlind2
7,823 Points
brandonlind2
brandonlind2
7,823 Points

thanks, I figured it would make it drier because var isn't being repeated for every object created, I didn't think about the names starting with a number, I fixed that and its working now thanks