usort Issues and Classes
| From: | Jason Mowat | Date: | Tue, 06 Feb 2001 20:52:39 +0000 |
| Subject: | usort Issues and Classes | ||
| Groups: | php.general | ||
| Request: | Send a blank email to php-general+get-38427@lists.php.net to get a copy of this message | ||
Greets,
I am playing around with usort and an LDAP class. Basically, I want to sort
the results of an LDAP search based on a specific criterion.
class CLDAP {
var $m_Entries;
var $m_LinkIdentifier;
...
function Connect() {
...
}
function Bind() {
...
}
function FindEntries($BaseDN, $Filter) {
$ProcName="CLDAP::FindEntries";
$LDAPSearchResult=ldap_search($this->m_LinkIdentifier, "$BaseDN",
"$Filter");
if($LDAPSearchResult) {
$Entries=ldap_get_entries($this->m_LinkIdentifier, $LDAPSearchResult);
if($Entries) {
//print "$ProcName: Entries found for filter of $Filter<br>";
$this->m_Entries = $Entries;
} else {
// No entries
//print "$ProcName: No entries found for filter of $Filter<br>";
}
}
}
//*************************
//* SORT CLASS MEMBERS
//*************************
function MySort() {
$ProcName = "CLDAP::MySort";
// Sort the entries ;
print "$ProcName: BEFORE: " . $this->m_Entries["count"] .
"<br>";
usort($this->m_Entries, array($this,"cmp"));
print "$ProcName: AFTER: " . $this->m_Entries["count"] .
"<br>";
}
function cmp ($a, $b) {
$ProcName = "CLDAP:cmp";
print "$ProcName: IN COMPARE: " . $this->m_Entries["count"] .
"<br>";
return strcmp($a["sn"],$b["sn"]);
}
}
Now, with the above (hacked up) example, I create my LDAP object, connect to
an LDAP server and retrieve values based on a DN and Filter. Essentially, I
get a multi-dimensional array populated with the results from my LDAP
filter, with key references to their attributes ("givenname" = first name,
"sn" = last name, etc...). This works! I can populate my object property
'$this->m_Entries' with my UNSORTED LDAP results.
When I run the $LDAP->MySort() routine, '$this->m_Entries' has values BEFORE
the usort function call, but has NULL entries AFTER the function call.
'$this->cmp' has values each time it is called. Somehow, my data is being
wiped out by usort after I return from '$this->cmp'. The above example is
attempting to sort my LDAP results by "sn", or last name in LDAP-ese.
What is happening here? Why is my array of results disappearing after the
usort? I played with globals, and I even saved my array into a temp
variable and used that instead. The temp variable is fine before the usort,
but is totally gone after. Any help is appreciated!
Cheers,
Jason