Javascript使用对象变量从数组中删除对象

Question

So I am trying to use arrays and for demonstration purposes I have condensed the code using points as examples. I want to create a point and push it to array and after doing stuff I want to remove the point from the array.

var PointArray = [];
function CreatePoint(X,Y){
    this.x=X;
    this.y=Y;
    PointArray.push(this);
}
function RemovePoint(PointObject){
     //????
}
var xPoint = CreatePoint(10,10);
//do stuff
RemovePoint(xPoint);

I was looking at the ‍ Array.prototype manual and PointArray.Splice seems like a the closest but feels messy since it wants indexs. Anyone have a clean way remove objects from array to shove into function RemovePoint ?

Answer 1

To find the index of something in an array, use indexOf :

function RemovePoint(PointObject){
  const index = PointArray.indexOf(PointObject);
  PointArray.splice(index, 1); // remove one item at index "index"
}

But if you're doing something like this, you might consider using a Set instead, which might be more appropriate if you want a collection, but the index of each object doesn't actually matter - then, you could just call PointSet.delete(PointObject); :

 const PointSet = new Set(); function CreatePoint(X,Y){ this.x=X; this.y=Y; PointSet.add(this); } function RemovePoint(PointObject){ PointSet.delete(PointObject); } console.log(PointSet.size); const xPoint = new CreatePoint(10,10); console.log(PointSet.size); RemovePoint(xPoint); console.log(PointSet.size); 

As comment notes, make sure to use new when calling a constructor like CreatePoint .

Answer 2

Why not use filter to remove elements from PointArray

var PointArray = [];
function CreatePoint(X,Y){
    this.x=X;
    this.y=Y;
    PointArray.push(this);
}
function RemovePoint(PointObject){
  PointArray = PointArray.filter(singlePoint=>!(singlePoint.x==PointObject.x && singlePoint.y==PointObject.y));
}
var xPoint = new CreatePoint(10,10);
var yPoint = new CreatePoint(20,20);
//do stuff
console.log(PointArray);
RemovePoint(xPoint);
console.log(PointArray);