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));   ?> |
Output:
int(2) int(1) int(1)
Reference: https://www.php.net/manual/en/splobjectstorage.removeallexcept.php
