The SplObjectStorage::attach() function is an inbuilt function in PHP which is used to add objects into the SplObjectStorage.
Syntax:
void SplObjectStorage::attach($obj, $val)
Parameters: This function accepts two parameters as mention above and described below.
- $obj: This is required parameter which specifies the object of the storage class.
- $val: This is an optional parameter which specified the values to be added.
Return Value: This function does not returns any value.
Below programs illustrate the SplObjectStorage::attach() function in PHP:
Program 1:
<?php   // Declare new object $obj = new StdClass;   // Create an empty storage class $str = new SplObjectStorage();   // Attach $obj with String "neveropen" $str->attach($obj, "neveropen");   // Print Result var_dump($str[$obj]);   ?> |
string(13) "neveropen"
Program 2:
<?php   // Creating std classes $obj1 = new StdClass; $obj2 = new StdClass; $obj3 = new StdClass; $obj4 = new StdClass;   $str = new SplObjectStorage(); $str->attach($obj1); $str->attach($obj2, "GFG");   // Another way to use attach() function $str[$obj3] = "neveropen"; $str[$obj4] = NULL ;   // Print Result var_dump($str[$obj1]); var_dump($str[$obj2]); var_dump($str[$obj3]); var_dump($str[$obj4]);   ?> |
NULL string(3) "GFG" string(13) "neveropen" NULL
Reference: https://www.php.net/manual/en/splobjectstorage.attach.php
