bind_param（）中变量的问题

Question

I have error_reporting all the way on and I've looked over it many times, so I think I might be calling a value wrong or didn't declare something correct. Anyone who can jump in and tell me whats up with the code and why still the error " Call to a member function bind_param() on a non-object" because I'm stumped:

$db=new mySQLi($host,$dbhuser,$dbhpwd,$dbh); 
$insert_stmt = $db->stmt_init();    
$insert_stmt = $db->prepare("INSERT INTO food (id,timestamp,userid,tagline,group,location,event_date,event_time,image,type) VALUES(NULL,NOW(),?,?,?,?,?,?,?,?)");
        $insert_stmt->bind_param("issssssi",$_SESSION['id'],$tagline,$organizer,$location,$event_date,$event_time,$image_name,$food_id);
        $insert_stmt->execute();

userid is an integer that I pull from a stored cookie.

$tagline, $organizer, $location, are text with max at 140 chars.

$event_date = $event_date= substr(date('Y'),0,2).$year."-".$month."-".$day; $event_time= date("H:i:s", strtotime($hour.":".$minute.$period)); - all these variable were users input as two digit numbers as text

$image_name is text, a file path

and type is an integer from 1-29.

Here is an example result of the ? values for the database: 38, test, test, test, 2013-2-20, 14:15:00, Halloween_Beer_2.jpg, 7

Here is a screen shot of the setup in mysql for the table called food:

Answer 1

$insert_stmt = $db->prepare("INSERT INTO food (id,timestamp,userid,tagline,group,location,event_date,event_time,image,type) VALUES(NULL,NOW(),?,?,?,?,?,?,?,?)");
        $insert_stmt->bind_param("issssssi",$_SESSION['id'],$tagline,$organizer,$location,$event_date,$event_time,$image_name,$food_id);
        $insert_stmt->execute();

you are doing wrong.BindParam accepts only a single value

$query->bindParam("value",":value",PDO::PARAM_INT);// type

you can do something like this

   $insert_stmt = $db->prepare("INSERT INTO food (id,timestamp,userid,tagline,group,location,event_date,event_time,image,type) VALUES(NULL,NOW(),?,?,?,?,?,?,?,?)");

$insert_stmt->execute(array("issssssi",$_SESSION['id'],$tagline,$organizer,$location,$event_date,$event_time,$image_name,$food_id))

Or you can see this PDO tutorial