Making Promises
We started this chapter by showing how the Ajax methods in jQuery 1.5+ ($.ajax, $.get, and $.post) return Promises. But to really understand Promises, we need to make a few of our own.
Letâs give the user a prompt to hit either Y or N. The first thing weâll do is create an instance of $.Deferred that represents the userâs decision.
| â | âvarâ promptDeferred = ânewâ $.Deferred(); |
| â | promptDeferred.always(âfunctionâ(){ console.log(â'A choice was made:'â); }); |
| â | promptDeferred.done(âfunctionâ(){ console.log(â'Starting game...'â); }); |
| â | promptDeferred.fail(âfunctionâ(){ console.log(â'No game today.'â); }); |
(Note: always is available only in jQuery 1.6+.)
Youâre probably wondering ...
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