php - how do i change this code mysql to pdo -

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• php - using pdo in clause array 3 answers

orignal php code

  $sql = "select * products id in(";             foreach($_session['cart'] $id => $value){             $sql .=$id. ",";           }             $sql=substr($sql,0,-1) . ") order id asc";             $query = mysql_query($sql);             $totalprice=0;             $totalqunty=0;             if(!empty($query)){             while($row = mysql_fetch_array($query)){                 $quantity=$_session['cart'][$row['id']]['quantity'];                 $subtotal= $_session['cart'][$row['id']]                 ['quantity']*$row['productprice'];                 $totalprice += $subtotal;                 $_session['qnty']=$totalqunty+=$quantity; 

i tried this

            $sql = $conn->prepare("select * products id in(");             foreach($_session['cart'] $id => $value){             $sql .= $id . ","; }             $sql.=substr($sql,0,-1) . ") order id asc";             $query = $conn->prepare($sql);             $query->execute();             $totalprice=0;             $totalqunty=0;             if(!empty($query)){             while($row = $query->fetch(pdo::fetch_assoc) ){                 $quantity=$_session['cart'][$row['id']]['quantity'];                 $subtotal= $_session['cart'][$row['id']]                 ['quantity']*$row['productprice'];                 $totalprice += $subtotal;                 $_session['qnty']=$totalqunty+=$quantity; 

but not working, shopping cart part code.so please can tell me how can change code in pdo , what's wrong written code in pdo.

you have add parameters execute

$query->execute(array_values($_session['cart'])); 

however should not use superglobals directly. should filter values , take care, variables not security threat.