comparing column in database to values in array of objects

i have this array of objects as a result of the following code:

$varIds = $this->user_model->get_var_id(...);

it produces something like this :

[
    {var_id: "141"}
    {var_id: "143"}
    {var_id: "146"}
    {var_id: "149"}
]

next step, sending this array to model like this:

$this->user_model->get_item_options_values_filter(...,$varIds);

next, filtering like this:

$this->db->where_in('items_options_value.var_id',$varIds);

i want to filter the rows based on the values in the $varIds array of objects, but this does not work as the where_in clause gives error array to string conversion, so how to compare the value of the var_id column with the values in $varIds?

Answer

i had to first convert array of objects into array of values like this :

     $names = array();
     foreach($varIds as $v){
         array_push($names,$v['var_id']);
     }

then :

     $this->db->where_in('items_options_value.var_id',$names);