Object of class stdClass could not be converted to string

You mentioned in another comment that you aren't expecting your get_userdata() function to return an stdClass object? If that is the case, you should mind this line in that function:

return $query->row();

Here, the CodeIgniter database object "$query" has its row() method called which returns an stdClass. Alternately, you could run row_array() which returns the same data in array form.

Anyway, I strongly suspect that this isn't the root cause of the problem. Can you give us some more details, perhaps? Play around with some things and let us know how it goes. We can't play with your code, so it's hard to say exactly what's going on.

In General to get rid of

Object of class stdClass could not be converted to string.

try to use echo '<pre>'; print_r($sql_query); for my SQL Query got the result as

stdClass Object
(
    [num_rows] => 1
    [row] => Array
        (
            [option_id] => 2
            [type] => select
            [sort_order] => 0
        )

    [rows] => Array
        (
            [0] => Array
                (
                    [option_id] => 2
                    [type] => select
                    [sort_order] => 0
                )

        )

)

---

In order to acces there are different methods E.g.: num_rows, row, rows

echo $query2->row['option_id'];

Will give the result as 2

I use codeignator and I got the error:

Object of class stdClass could not be converted to string.

for this post I get my result

I use in my model section

$query = $this->db->get('user', 10);
        return $query->result();

and from this post I use

$query = $this->db->get('user', 10);
        return $query->row();

and I solved my problem

Most likely, the userdata() function is returning an object, not a string. Look into the documentation (or var_dump the return value) to find out which value you need to use.