defaultifempty.md

Rx.Observable.prototype.defaultIfEmpty([defaultValue])

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Returns the elements of the specified sequence or the specified value in a singleton sequence if the sequence is empty.

Arguments

1. [defaultValue=null] (Any): The value to return if the sequence is empty. If not provided, this defaults to null.

Returns

(Observable): An observable sequence that contains the specified default value if the source is empty; otherwise, the elements of the source itself.

Example

Without a default value

With a defaultValue