Syntax:

void SplObjectStorage::detach ($obj)

Parameters: This function takes one parameter, $obj,which specifies the object to be removed from storage.Return Value:This function does not return any value.The following programs illustrate the SplObjectStorage::detach() functionin PHP:Program 1:  
// Create a class $obj = new StdClass;  
// Create empty storage class $str = new SplObjectStorage();  
// Add object $str -> attach ( $obj , "GeeksforGeeks" );  
// Print the result before disconnecting var_dump ( count ( $str ));  
// Detach the object $str -> detach ( $obj );  
// Print the result after disconnecting var_dump ( count ( $str )); ?> Exit:

int (1 ) int (0)

Program 2:  
// Create a class $obj1 = new StdClass; $obj2 = new StdClass; $obj3 = new StdClass;  
// Create empty storage class $str = new SplObjectStorage();  
// Add object $str -> attach ( $obj1 , "GeeksforGeeks" ); $str -> attach ( $obj2 ); $str -> attach ( $obj3 , "GFG" );  
// Print the result before disconnecting var_dump ( count ( $str ));  
// Detach the object $str -> detach ( $obj1 );  
// Print the result after detaching the first object var_dump ( count ( $str ));  
// Detach the object $str -> detach ( $obj3 );  
// Print the result after detaching the second object var_dump ( count ( $str )); ?> Exit:

int (3 ) int (2) int (1)

Link: https : //www.php.net/manual/en/splobjectstorage.detach.php