Regarding multiple request issues with ajax

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We may encounter when using ajax to request data Possibility of triggering multiple times with one click.

(For example: ajax's onreadystatechangeeventwill be triggered multiple times; this is because onreadystatechange is an event handle.

Its value (state_Change) is aThe name of the function, this function will be triggered when the state of the XMLHttpRequestobject

## changes from 0 (uninitialized) to 4 (complete) only. We only execute the code when the state is 4. "

This function will be triggered every time the state of the XMLHttpRequest object changes.

It will be triggered 4 times in total, from 0 to 4. ) [PS: Of course, the examples cited in

here are not entirely consistent with the problems encountered at work] At this time, we need a method to terminate the program

exit and abort. Both are functions used to terminate the program. Let’s talk about the differences between the two.

##exit will do some release work:

Release allstaticglobal objects,cache, close all I/O channels, and then terminate the program. If there is a function registered through atexit, the registered function will also be called. . However, if the atexit function throws an exception, terminate will be called directly.##abort:

Terminate the program immediately without any cleanup work. ##The above is the entire content of the multiple ajax request issues brought to you by the editor. I hope you will support the PHP Chinese website~Related recommendations:

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