mysqli_multi_query database class error - php

Question

I am sure of this that this question hasn't asked anywhere even on the blog of creator of this class.
since morning i have started using php database class of bennettstone. I was trying to add MYSQLI_MULTI_QUERY into this class to handle multiple queries at once.
till now, I have been able to modify up to below extent. But it is not working. I am extremely poor with classes & this is my first attempt ever !!
I am getting error at two lines & don't know how i will access the result set of multiple queries. let's say 3 queries.
1) Error at while statement And similar error at mysqli_free_result statement
Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given on line 352
Request some help:
public function multi_select_query( $query )
{
$i = 0;
$row = array();
$query = $this->link->multi_query( $query );
if ( mysqli_error( $this->link ) ) {
$this->log_db_errors( mysqli_error( $this->link ), $query, 'Fatal' );
return false;
} else {
do {
$i ++;
$result[$i] = mysqli_store_result($this->link);
while ( $r = mysqli_fetch_array( $query, MYSQLI_ASSOC )) {
$row[$i][] = $r;
}
mysqli_free_result( $query );
} while ( $this->link->more_results() && $this->link->next_result() );
return $row[$i];
}
}

Answer 1

Finally, I made it myself somehow.
Below is the final working class example which can be easily accessed by foreach loop using following statement.
$result = $dbc->multi_select_query($query);
public function multi_select_query( $query )
{
$row = array();
$i = 0;
$query = $this->link->multi_query( $query );
if( mysqli_error( $this->link ) ){
$this->log_db_errors( mysqli_error( $this->link ), $query, 'Fatal' );
return false;
} else {
do{
$i ++;
if($result[$i] = $this->link->store_result())
{
while ($r[$i] = $result[$i]->fetch_row())
{
$row[$i][] = $r[$i];
}
$result[$i]->free();
}
} while( $this->link->more_results() && $this->link->next_result() );
return $row;
}
}