API Docs for: 1.0 pre
Show:

Ember.Map Class

A Map stores values indexed by keys. Unlike JavaScript's default Objects, the keys of a Map can be any JavaScript object.

Internally, a Map has two data structures:

  1. keys: an OrderedSet of all of the existing keys
  2. values: a JavaScript Object indexed by the Ember.guidFor(key)

When a key/value pair is added for the first time, we add the key to the keys OrderedSet, and create or replace an entry in values. When an entry is deleted, we delete its entry in keys and values.

Constructor

Ember.Map

() private

Item Index

Methods

Properties

Methods

create

() static

forEach

(
  • callback
  • self
)

Iterate over all the keys and values. Calls the function once for each key, passing in the key and value, in that order.

The keys are guaranteed to be iterated over in insertion order.

Parameters:

  • callback Function
  • self

    if passed, the this value inside the callback. By default, this is the map.

get

(
  • key
)

Retrieve the value associated with a given key.

Parameters:

  • key

Returns:

:

the value associated with the key, or undefined

has

(
  • key
)
Boolean

Check whether a key is present.

Parameters:

  • key

Returns:

Boolean:

true if the item was present, false otherwise

remove

(
  • key
)
Boolean

Removes a value from the map for an associated key.

Parameters:

  • key

Returns:

Boolean:

true if an item was removed, false otherwise

set

(
  • key
  • value
)

Adds a value to the map. If a value for the given key has already been provided, the new value will replace the old value.

Parameters:

  • key
  • value

Properties

length

Number

This property will change as the number of objects in the map changes.

Default: 0