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Start your free trialMayank Munjal
Front End Web Development Techdegree Graduate 18,120 PointsSo xhr.onreadystangechange is the callback function but I'm getting confused as to when it is called back?
I don't see a higher order function using the callback function as an argument so if someone can explain what's going on, it will help a lot!
1 Answer
Steven Parker
231,072 PointsThe callback function is used by an internal event handler that is established by the "xhr.send()
" call. It accesses the callback directly as a property of the "xhr" object instead of having it passed as an argument.