How to delete an object from array of objects in javascript

Question

Can anyone guide me in deleting an object from array of objects in javascript

Here's my javascript code

<script>
  var line  = {lines:[]};

  function change(num){
    line.lines.push({"linechange":num});
  }
</script>

Here num is some integer value, Is there a way to delete the pushed object based on the value of num?

Did you try anything after having searched ? What's the problem ? Hint: look for the index, then delete the element at the given index. Or if you can afford a different array object, filter it. — Denys Séguret, Sep 03 '15 at 06:50
[Array.prototype.filter()](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Array/filter) can help you. — Satpal, Sep 03 '15 at 06:51
@Satpal Depends: it's important to note that filter doesn't remove an element from an array but gives a **new** array. — Denys Séguret, Sep 03 '15 at 06:51
@DenysSéguret, Thats why in I used `can` and `line.lines = line.lines.filter(function( obj ) { return obj.linechange !== someVariable; })` will do — Satpal, Sep 03 '15 at 06:54
@DenysSéguret hi , is there a way to do "look for the index" without for loop ? — user8244016, Aug 25 '17 at 20:03
@user8244016 yes there are. Search for "javascript array functions mdn". — Denys Séguret, Aug 25 '17 at 20:04
@DenysSéguret thank you ,I used `.findIndex` and in the inner function I put `element.property=mydesiredvalue;`, — user8244016, Aug 25 '17 at 20:47

score 0 · Answer 1 · edited May 23 '17 at 12:29

0

Delete in this case will only set the element as undefined:

> myArray = ['a', 'b', 'c', 'd']
  ["a", "b", "c", "d"]
> delete myArray[0]
  true
> myArray
  [undefined, "b", "c", "d"]

Splice actually removes the element from the array:

> myArray = ['a', 'b', 'c', 'd']
  ["a", "b", "c", "d"]
> myArray.splice(0, 2)
  ["a", "b"]
> myArray
  ["c", "d"]

A simple search and you got this by yourself. Reference: Deleting array elements in JavaScript - delete vs splice

edited May 23 '17 at 12:29

Community

answered Sep 03 '15 at 06:54

The above have different outcomes, but **both** remove elements from the array. In the first case, the *0* property is deleted and no other property is affected. This missing property is represented as *undefined*, but it doesn't exist (try `myArray.hasOwnProperty('0')`). In the second example, *splice* not only removes the members, but shifts all subsequent indexes to "fill" the empty space created. So when *0* and *1* are removed, *2* and *3* are shifted down to become *0* and *1*. – RobG Sep 03 '15 at 07:17

1 Answers1