ReadOnlyObservableCollection.map

API / ReadOnlyObservableCollection<TItem> / map method

Creates a new JavaScript Array constructed by mapping each item in the collection using a callback.

This is a public method.

public map<TResult>(callbackfn: (item: TItem, index: number, collection: IReadOnlyObservableCollection<TItem>) => TResult): TResult[]

Template Parameters

• TResult: the type to map each item to.

Parameters

• callbackfn: Function, the callback mapping each item.

  Parameters:

  • item: TItem, the item being mapped.
  • index: Number, the index of the item being mapped.
  • collection: IReadOnlyObservableCollection<TItem>, the collection being iterated.

  Returns: TResult

  Returns the mapped item.

Returns: TResult[]

A new Array containing the mapped items.

See

• Array.map

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Creates a new JavaScript Array constructed by mapping each item in the collection using a callback.

This is a public method.

public map<TResult, TContext>(callbackfn: (this: TContext, item: TItem, index: number, collection: IReadOnlyObservableCollection<TItem>) => TResult, thisArg: TContext): TResult[]

Template Parameters

• TResult: the type to map each item to.
• TContext: the context type in which the callback is executed.

Parameters

• callbackfn: Function, the callback mapping each item.

  Parameters:

  • item: TItem, the item being mapped.
  • index: Number, the index of the item being mapped.
  • collection: IReadOnlyObservableCollection<TItem>, the collection being iterated.

  Returns: TResult

  Returns the mapped item.
• thisArg: TContext, a value to use as the callback context when mapping items.

Returns: TResult[]

A new Array containing the mapped items.

See

• Array.map