These are two functions to manipulate PHP objects.

The first function is similar to array_merge function in that it merges two objects based on an index.

The second function in_object also acts like in_array to which it checks if a certain index exists in an array at a specific value.

Hopefully someone finds it helpful.

<?php

// Object merge and in Object functions
function object_merge($objectFrom,$objectTo,$indexUse) 
{ 
    $objectReturn = array(); 
    foreach($objectFrom as $curObject) 
    {         
        $index = in_object($indexUse,$curObject->$indexUse,$objectTo,true); 
        if(is_int($index)) 
        { 
            foreach($objectTo[$index] as $indexName => $indexValue) 
            { 
                $curObject->$indexName = $indexValue; 
            } 
        } 
        $objectReturn[] = (object) $curObject;         
    } 
    return $objectReturn; 
} 

function in_object($searchFor,$searchValue,$objectSearch,$returnResult) 
{ 
    foreach($objectSearch as $index => $thisObject) 
    { 
        if($thisObject->$searchFor == $searchValue) 
        { 
            if($returnResult) 
            { 
                return $index; 
            } else { 
                return true; 
            } 
        } 
    } 
    return false; 
} 

// Usage 
$obj1[0] = (object) array('catId' => 1, 'catName' => 'Name'); 
$obj1[1] = (object) array('catId' => 2, 'catName' => 'Name2'); 

$obj2[0] = (object) array('catId' => 1, 'catDesc' => 'Desc'); 
$obj2[1] = (object) array('catId' => 2, 'catDesc' => 'Desc2'); 

$obj_merged = object_merge($obj1,$obj2,'catId'); 
print_r($obj_merged);