sys_get_temp_dir
<?php
// quick & dirty way to barricade your code during version transitions
assert('version_compare("5", PHP_VERSION, "<"); // requires PHP 5 or higher');
?>
version_compare
(PHP 4 >= 4.0.7, PHP 5)
version_compare — Confronta due stringhe contenenti il numero di versione di "PHP-standardized"
Descrizione
int version_compare
( string $version1
, string $version2
[, string $
operator
] )
version_compare() confronta due numeri di versione "PHP-standardized" . Questa funzione è utile quando si desideri che funzioni solo con alcune versioni di PHP.
La funzione version_compare() restituisce -1 se la prima verisone è minore della seconda, 0 se sono uguali, +1 se la sceonda è inferiore.
Per prima cosa la funzione sostituisce nella strina di versione le lettere _, - e + con un puntot . ed inserisce un punto . prima e dopo ogni carattere non numerico, in modo che, ad esempio, '4.3.2RC1' diventi ''4.3.2.RC.1'. Quindi divite il testo come se usasse explode('.', $ver). Poi confronta le parti cominciando da sinistra verso destra Se una parte contiene versioni speciali queste sono gestite nel seguente modo: dev < alpha = a < beta = b < RC < pl. In quest modo possono essere confrontati non solo differenti livelli di versioni quali '4.1' e '4.1.2', ma anche versioni di PHP in fase di sviluppo.
Specificando il terzo parametro opzionale operator si possono testare particolari relazioni. I possibili operatori sono: <, lt, <=, le, >, gt, >=, ge, ==, =, eq, !=, <>, ne. Utilizzando questi parametri, la funzione restituirà 1 se la relazione è una di quelle specificate dall'operatore, altrimenti 0.
Example #1 Esempio di uso di version_compare()
<?php
// prints -1
echo version_compare("4.0.4", "4.0.6");
// queste stampano 1
echo version_compare("4.0.4", "4.0.6", "<");
echo version_compare("4.0.6", "4.0.6", "eq");
?>
add a note
User Contributed Notesversion_compare
bishop
07-Mar-2008 10:54
07-Mar-2008 10:54
Rickard Andersson
30-Oct-2007 02:18
30-Oct-2007 02:18
It should be noted that version_compare() considers 1 < 1.0 < 1.0.0 etc. I'm guessing this is due to the left-to-right nature of the algorithm.
Jonathon dot Reinhart at gmail dot com
30-Oct-2007 08:38
30-Oct-2007 08:38
I know this is somewhat incomplete, but it did a fair enough job for what I needed. I was writing some code that needed done immediately on a server that was to be upgraded some time in the future. Here is a quick replacement for version_compare (without the use of the operator argument). Feel free to add to this / complete it.
<?php
function version_compare2($version1, $version2)
{
$v1 = explode('.',$version1);
$v2 = explode('.',$version2);
if ($v1[0] > $v2[0])
$ret = 1;
else if ($v1[0] < $v2[0])
$ret = -1;
else // Major ver are =
{
if ($v1[1] > $v2[1])
$ret = 1;
else if ($v1[1] < $v2[1])
$ret = -1;
else // Minor ver are =
{
if ($v1[2] > $v2[2])
$ret = 1;
else if ($v1[2] < $v2[2])
$ret = -1;
else
$ret = 0;
}
}
return $ret;
}
?>
opendb at iamvegan dot net
10-Jun-2007 05:01
10-Jun-2007 05:01
Something that may trip some folks up, but is useful to mention is that the following version comparison does not work quite as I expected:
version_compare('1.0.1', '1.0pl1', '>')
However, its quite easy to get working:
version_compare('1.0.1', '1.0.0pl1', '>')
arnoud at procurios dot nl
29-Sep-2004 02:28
29-Sep-2004 02:28
If you're careful, this function actualy works quite nicely for comparing version numbers from programs other than PHP itself. I've used it to compare MySQL version numbers. The only issue is that version_compare doesn't recognize the 'gamma' addition that mysql uses as being later than 'alpha' or 'beta', because the latter two are treated specially. If you keep this in mind though, you should have no problems.
mina86 at tlen dot pl
30-Jun-2004 07:40
30-Jun-2004 07:40
Here's a wrapper which is more tolerant as far as order of arguments is considered:
<?php
function ver_cmp($arg1, $arg2 = null, $arg3 = null) {
static $phpversion = null;
if ($phpversion===null) $phpversion = phpversion();
switch (func_num_args()) {
case 1: return version_compare($phpversion, $arg1);
case 2:
if (preg_match('/^[lg][te]|[<>]=?|[!=]?=|eq|ne|<>$/i', $arg1))
return version_compare($phpversion, $arg2, $arg1);
elseif (preg_match('/^[lg][te]|[<>]=?|[!=]?=|eq|ne|<>$/i', $arg2))
return version_compare($phpversion, $arg1, $arg2);
return version_compare($arg1, $arg2);
default:
$ver1 = $arg1;
if (preg_match('/^[lg][te]|[<>]=?|[!=]?=|eq|ne|<>$/i', $arg2))
return version_compare($arg1, $arg3, $arg2);
return version_compare($arg1, $arg2, $arg3);
}
}
?>
It also uses phpversion() as a default version if only one string is present. It can make your code look nicer 'cuz you can now write:
<?php if (ver_cmp($version1, '>=', $version2)) something; ?>
and to check a version string against the PHP's version you might use:
<?php if (ver_cmp('>=', $version)) something; ?>
instead of using phpversion().
eric at themepark dot com
21-Jun-2004 09:50
21-Jun-2004 09:50
[editors note]
snipbit fixed after comment from Matt Mullenweg
--jm
[/editors note]
so in a nutshell... I believe it works best like this:
<?php
if (version_compare(phpversion(), "4.3.0", ">=")) {
// you're on 4.3.0 or later
} else {
// you're not
}
?>
sam at wyvern dot non-spammers-remove dot com dot au
23-May-2004 11:18
23-May-2004 11:18
Actually, it works to any degree:
<?php
version_compare('1.2.3.4RC7.7', '1.2.3.4RC7.8')
version_compare('8.2.50.4', '8.2.52.6')
?>
will both give -1 (ie the left is lower than the right).