class_exists
Name
class_exists — Tests whether a class is defined.
Synopsis
bool class_exists
(class_name);
string class_name: Name of
the class whose existence is being tested
Returns
TRUE if the class exists; FALSE for all other cases
Description
class_exists() is used to check whether a class
has been defined. If the class has been defined, the
function returns TRUE; otherwise, it returns
FALSE.
Version
PHP Version: 4.0b4+
See also
To find the type of a variable:
gettype()
To find out whether a variable is an object:
is_object()
Example
Example 101. Check to see
whether a class is defined
// Why no class can be a nihilist
class nihilist {
function nihilist () {
print ""; // Ha ha - sorry for the crummy nihilist humor...
}
}
if (class_exists ('nihilist'))
print "Class <i>nihilist</i> exists.";
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
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