The class_exists() function is an inbuilt function in PHP which is used to check whether the given class is defined or not.
Syntax:
bool class_exists( string $class_name, bool $autoload = TRUE )
Parameters: This function accept two parameters as mentioned above and described below:
- $class_name: It holds the class name which need to check their existence.
- $autoload: It checks whether the __autoload is called or not by default.
Return Value: This function returns True if class name is defined otherwise returns False.
Below programs illustrate the class_exists() function in PHP:
Program 1:
<?php // Create a class class GFG {
public $Geek_name = "Welcome to GeeksforGeeks" ;
} // Check class name exist or not if ( class_exists ( 'GFG' )) {
echo "Class name exists" ;
} else {
echo "Class name does not exist" ;
} ?> |
Output:
Class name exists
Program 2:
<?php // Creating class class GFG {
public $data1 ;
public $data2 ;
public $data3 ;
} if ( class_exists ( 'GFG' )) {
// Creating an object
$obj = new GFG();
// Set values of $obj object
$obj ->data1 = "Geeks" ;
$obj ->data2 = "for" ;
$obj ->data3 = "Geeks" ;
// Print values of $obj object
echo "$obj->data1 \n$obj->data2 \n$obj->data3" ;
} else {
echo "Class does not exist" ;
} ?> |
Output:
Geeks for Geeks
Reference: https://www.php.net/manual/en/function.class-exists.php