创建对象数组Javascript

Question

I created this Object with 3 properties:

Node = {
    name : "",
    isOkay : true,
    rotation : 0.0
}; 

How would i go creating an array of these objects, in size of 100.

So later i could do something like this:

nodeList[74].name = "Peter";

nodeList[74].isOkay = false;

nodeList[74].rotation = 1.3;

or similar...

I'm really new to this, i found couple of topics about this, but it never compiles properly.

I would be really grateful if anyone could show the proper syntax, Thanks!

Answer 1

I would use this way:

var Node = function() {
    this.name = "";
    this.isOkay = true;
    this.rotation = 0.0
}

var nodeList = [];
for (var i = 0; i < 10; i++) 
{ 
    nodeList.push(new Node()); 
}

nodeList[0].name = "test";

So you could create a new object(really new) in order to manage it later. Look here .

EDIT :

What I have done is created an object with a constructor method, you can check it on MDN here .

Creating an object like you have done:

var Node = { /* ... */ }

Is like having one object initiated. To have another, you'll have to write another one and so on. With that contructor you may create any instances you want based on that model .

Answer 2

You might want to do this lazily

Depending on the situation might be helpful to do this lazily

var Node = function(name, isOkay,rotation){
    if(!(this instanceof Node)) return new Node(name,isOkay,rotation);
    else {
        this.name = name;
        this.isOkay = isOkay;
        this.rotation = rotation;
    }
}

var NodeCollective = function(numberOfNodes){
        if(!(this instanceof NodeCollective)) return new NodeCollective(numberOfNodes);
        else{
                var _collective={};
                var _defaultName = "", _defaultIsOkay = true, _defaultRotation=0.0;
                this.length = numberOfNodes;
                this.getNode=function(nodeNumber){
                    if(!_collective.hasOwnProperty(nodeNumber) && nodeNumber < numberOfNodes){
                        _collective[nodeNumber]=
                            Node(_defaultName,_defaultIsOkay,_defaultRotation);
                    }
                    //I am just assuming I am not going to get garbage
                    //you can put in checks to make sure everything is kosher
                    //if you really want to
                    return _collective[nodeNumber];
                };
        }
}

but it also depends on what you are trying to do... if you might not be getting all of the nodes in your program then implementing them in some way that avoids greedily creating them could save you a lot of time if the code is executed often, but if the piece of code isn't executed often this might be over kill.

Answer 3

var nodeList = [];          // create empty array
nodeList.push(Node);        // add the object to the end of the array
nodeList[0].rotation = 1.3; // set rotation property of the object
console.log(nodeList[0]);   // prints the object to console