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Start your free trialHsinTzu Chen
5,833 PointsDoes send(null) had impact on asynchronous behavior?
I think the synchronous and asynchronous behaviors in first and second example is made by third argument in open method (true: asynchronous or false: synchronous).
However, there is also difference in send method first example (synchronous )-->xhr.send(null)
and second example (synchronous )-->xhr.send()
.
I am wondering if null argument has impact on asynchronous behavior? If not, does anyone knows why null argument is used? Many Thanks!
2 Answers
Steven Parker
231,184 PointsIf you look at the MDN documentation for xhr.send(), you'll find that it says "If no value is specified for the body, a default value of null is used."
So it's simply programmer's preference, either an empty argument or an explicit null
will produce the same behavior.
HsinTzu Chen
5,833 PointsSteven Parker , I see. Next time, I will try to check official document first. Thank you for your explanation!