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(PHP 4, PHP 5)
connection_status — Liefert den Verbindungsstatus als Bitfeld
Gibt den Verbindungsstatus als Bitfeld zurück.
Der Verbindungsstatus als Bitfeld, der zusammen mit den CONNECTION_XXX-Konstanten verwendet werden kann, um den Verbindungsstatus zu ermitteln.
You can always send chr(0) to check if browser is still alive, that will show no output in browser page (at least in Firefox).
Good idea for DB engines like MySQL with MyISAM which do not support transactions. But imagine that user requests a page with many (hundred) image thumbnails. Or if a PDF is generated from a HTML on-the-fly. This usually takes several minutes and if the user does not want to wait and aborts connection - PHP continues until all work is done.
In my opinion it will be MUCH more smarter (PHP is mature enough) to use signalling and terminate script immediately when connection is aborted instead of making presumptions that script author will continuously doing output and periodically flushing output buffer just in order to detect connection abort.
Mhm ....
Yes it is true. I made some experiments with that functions 'connection_abortes()'. First a source made an error, which I see. They wrote: ignore_user_abort();
But that only gives you the status of the 'Abort-Setting'.
So I try (with little hope)
'ignore_user_abort(true);'
And as I readout the setting it has changed it...
Next I see that the script runs after I disconnect with the site. But other experiments fail. I try some things and then it
was logical after an experiment: flush() is one of the necessary things. Without those output to the client the function
'connection_aborted()' stays on 'false'
The Second is that you have to output something. Without that it also doesn't works.
So I now know that you have to echo something and then output the buffer. Only then 'the Script' (or the function)
'knows' that the client is disconnected.
Notice !
if you running a loop (while, foeach etc..) you have to send something to the browser to check the status.
Example:
while(1){
if (connection_status()!=0){
die;
}
}
doesnt work, if the user break/close the browser.
But a:
while(1){
Echo "\n"; //<-- send this to the client
if (connection_status()!=0){
die;
}
}
will work :)
i hope it will help some of you to safe some time :)
Toppi
Very very useful!
I was building a chat and I wanted my script to detect when the browser was closed, so the user could be deleted from the online_users table.
<?
echo str_repeat(" ",300);
ignore_user_abort(true); //this way, the user can stop the output, but not the script.
while (true) {
echo "test<br>\n";
flush();
sleep(2);
if (connection_status()!=0){
include ('dbconnect.inc');
$sql="delete from online_users where online_user=$user";
$sql_exec=pg_exec($vChatDB, $sql);
die(); //kills the script
}
}
?>
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