Win8: asynchronous programming in JavaScript with "Promises"

Promises is a feature of winjs and is designed to deal with asynchronous JS issues.

PromiseMode is in one of the following three States at any time: incomplete (Unfulfilled), Completed (Resolved) And reject (Rejected).

ThenMethod returns anotherPromiseObject To facilitate the formationPromisePipeline, which returnsPromiseThe object method supports developers to concatenate asynchronous operations, suchThen (resolvedhandler, rejectedhandler );

ResolvedhandlerThe callback function is inPromiseWhen the object enters the completion state, it is triggered and the result is passed;RejectedhandlerThe function is called in the rejected status. Take a look at the following example:

 

 

Check more content: http://blogs.msdn.com/ B /ie/archive/2011/09/11/asynchronous-programming-in-javascript-with-promises.aspx