用Ajax停止PHP

I have a JavaScript functions which calls a PHP function through AJAX. The PHP function has a set_time_limit(0) for its purposes. Is there any way to stop that function when I want, for example with an HTML button event?

I want to explain better the situation: I have a php file which uses a stream_copy_to_stream($src, $dest) php function to retrieve a stream in my local network. The function has to work until I want: I can stop it at the end of the stream or when I want. So I can use a button to start and a button to stop. The problem is the new instance created by the ajax call, in fact I can't work on it because it is not the function that is recording but it is another instance. I tried MireSVK's suggest but it doesn't worked!

Depending on the function. If it is a while loop checking for certain condition every time, then you could add a condition that is modifiable from outside the script (e.g. make it check for a file, and create / delete that file as required)

It looks like a bad idea, however. Why you want to do it?

var running = true;

function doSomething(){

       //do something........
}

setInterval(function(){if(running){doSomething()}},2000); ///this runs do something every 2 seconds

on button click simply set running = false;

Your code looks like:

set_time_limit(0);

while(true==true){//infinite loop

 doSomething(); //your code

}

Let's upgrade it

set_time_limit(0);

session_start();
$_SESSION['do_a_loop'] = true;

function should_i_stop_loop(){

   @session_start(); 

   if( $_SESSION['do_a_loop'] == false ) {

    //let's stop a loop
    exit();

   }

   session_write_close(); 

}

while(true==true){

 doSomething();

 should_i_stop_loop(); //your new function

}

Create new file stopit.php

session_start();
$_SESSION['do_a_loop'] = false;

All you have to do now is create a request on stopit.php file (with ajax or something)

Edit code according to your needs, this is point. One of many solutions.

Sorry for my English

Sadly this isn't possible (sort of).

Each time you make an AJAX call to a PHP script the script spawns a new instance of itself. Thus anything you send to it will be sent to a new operation, not the operation you had previously started.

There are a number of workarounds.

• Use readystate 3 in AJAX to create a non closing connection to the PHP script, however that isn't supported cross browser and probably won't work in IE (not sure about IE 10).

• Look into socket programming in PHP, which allows you to create a script with one instance that you can connect to multiple times.

• Have PHP check a third party. I.E have one script running in a loop checking a file or a database, then connect to another script to modify that file or database. The original script can be remotely controlled by what you write to the file/database.

• Try another programming language (this is a silly option, but I'm a fan of node). Node.js does this sort of thing very very easily.