PHP SplObjectStorage removeAllExcept() Function

Last Updated : 23 Jun, 2023

The SplObjectStorage::removeAllExcept() function is an inbuilt function in PHP which is used to remove all objects from storage except for those contains by another storage.

Syntax:

int SplObjectStorage::removeAllExcept()

Parameters: This function accepts a single parameter $obj which specify object storage to be retain.

Return Value: This function does not return any value.

Below programs illustrate the SplObjectStorage::removeAllExcept() function in PHP:

Program 1:

<?php 
  
$obj1 = new StdClass; 
$obj2 = new StdClass; 
$obj3 = new StdClass; 
  
$gfg1 = new SplObjectStorage(); 
$gfg1[$obj1] = "Geeks"; 
  
$gfg2 = new SplObjectStorage(); 
$gfg2[$obj1] = "GFG"; 
$gfg2[$obj2] = "GeeksClasses"; 
$gfg2[$obj3] = "SUDO"; 
  
// Count all existing objects 
var_dump(count($gfg2)); 
  
// Remove all objects of $gfg2 from $gfg2 
$gfg2->removeAllExcept($gfg1); 
  
// Print result after removeAll 
var_dump(count($gfg2)); 
?> 

Output:

int(3)
int(1)

Program 2:

<?php 
  
$obj1 = new StdClass; 
$obj2 = new StdClass; 
  
$gfg1 = new SplObjectStorage(); 
$gfg1[$obj1] = "Geeks"; 
  
$gfg2 = new SplObjectStorage(); 
$gfg2[$obj1] = "GFG"; 
$gfg2[$obj2] = "GeeksClasses"; 
  
// Count and print all existing objects 
var_dump(count($gfg2)); 
  
// Remove all objects of $gfg1 from $gfg2 
$gfg2->removeAllExcept($gfg1); 
  
// Print result   
var_dump(count($gfg2)); 
  
// Result remains same 
$gfg2->removeAllExcept($gfg2); 
  
// Print result   
var_dump(count($gfg2)); 
  
?> 