javascript splicing array

Question

I have an array of object and I'm looking to remove an element. However, the splice method seems to return the element removed, not the array without the element I wanted to remove.

This is what I have

var TheArray = TheObject.Array;
TheArray = TheArray.splice(TheIndex, 1); //TheIndex is the index of the element I want to remove
TheObject.Array = TheArrray;

When I debug and run this code, TheObject.Array contains the element I wanted to remove.

What am I doing wrong? Thanks for your suggestions.

Possible duplicate: http://stackoverflow.com/questions/500606/javascript-array-delete-elements — Colin Brock, Nov 16 '11 at 21:31

Jon Newmuis · Answer 1 · 2011-11-16T21:38:37.767

16

splice returns the removed element, but modifies the element on which it was called. So in your example, TheArray is updated in place, and should no longer contain the removed element.

A more concrete, simplified example of how to use splice is as follows:

var myArr = ["a", "b", "c", "d"];
var elem = myArr.splice(2, 1);
// elem  => ["c"]
// myArr => ["a", "b", "d"]

edited Nov 16 '11 at 21:38

answered Nov 16 '11 at 21:33

Jon Newmuis

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score 9 · Accepted Answer · answered Nov 16 '11 at 21:36

9

You are setting the value of TheArray to that of the item you are removing.

Rewrite your code like this:

var TheArray = TheObject.Array;
TheArray.splice(TheIndex, 1); //TheIndex is the index of the element I want to remove
TheObject.Array = TheArrray;

answered Nov 16 '11 at 21:36

Kevin Anthony Oppegaard Rose

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Those three lines of code can be replaced with `TheObject.Array.splice(TheIndex,1)`. – Narendra Yadala Nov 16 '11 at 21:40
Indeed they can but I wanted to keep the solution as simple as possible to understand. The asker should now know not to bother with the TheArray= part of his code. He can then work out the rest himself. :) – Kevin Anthony Oppegaard Rose Nov 16 '11 at 21:42

score 0 · Answer 3 · answered Nov 16 '11 at 21:37

0

do an alert on your array to make sure the array is correct, also you may need to do a parseInt() around your variable (ie TheArray = TheArray.splice(parseInt(TheIndex), 1);) to make sure it's set to be an integer and not a string :)

i hope this helps

answered Nov 16 '11 at 21:37

Robert Van Sant

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Then at least use `parseInt(..., 10)`. – pimvdb Nov 16 '11 at 21:39

javascript splicing array

3 Answers3