How to empty a Backbone.js collection

Question

I was surprised to discover that this doesn't work:

coll = new Backbone.Collection
for i in [1..1000]
  coll.add new Backbone.Model()

console.log coll.length # 1000
coll.remove coll.models
console.log coll.length # 500!

I understand why this strange result occurs, more or less, though it seems like a bug to me. In any event, what's the best alternative, without resorting to internal methods like _reset (which wouldn't work anyway, as I want the appropriate remove event to be triggered)?

Solution 1

The easiest way to do this is to call .reset()^[docs] on the collection.

Calling collection.reset() without passing any models as arguments will empty the entire collection.

i.e.

collection.reset();

Solution 2

Personnaly i use:

_.invoke(collection.toArray(), 'destroy');

wich delete every element of the collection by calling the destroy method

Comments

[yves amsellem]

This will empty the collection on the client, not on the server.

[Trevor Burnham]

Worth noting that as of Backbone 0.5.0, released today, refresh has been renamed reset (a much clearer name, IMHO).

[jabbett]

Note: Collection.reset() issues a single "reset" event at the end, per the docs. It does not trigger "remove" events on the models that have been removed.