mysql_real_escape_string() expects parameter 2 to be resource, object given in,该怎么解决

mysql_real_escape_string() expects parameter 2 to be resource, object given in
代码如下：

$page_title = 'Register ';
include("header.html"); #网页头部
?>


if(isset($_POST['submitted'])){
require_once("mysqli_connect.php");
 
$error=array(); #定义错误为数组
if (empty($_POST['first_name'])){
$error[]='you forgot to enter you first name';
}else{
$fn= mysql_real_escape_string(trim($_POST['first_name']),$dbc);
  } #first name 条件语句
 
if (empty($_POST['last_name'])) {
$error[]='you forgot to enter you last name';
}else{
$ln= mysql_real_escape_string(trim($_POST['last_name']),$dbc);
} #last name 条件语句
 
if (empty($_POST['email'])){
$error[]='you forgot to enter you email';
}else{
$e= mysql_real_escape_string(trim($_POST['email']),$dbc);
} # email 条件语句
if (!empty($_POST['password1'])) {
if($_POST['password1']!=$_POST['password2']){
$error[]='your password did not match the confirmed password.';
}else{
$p= mysql_real_escape_string(trim($_POST['password1']),$dbc);
}  
}else{
$error[]='you forgot to your password'; 
} # password 条件语句  


if(empty($error)){

$q="INSERT INTO users (first_name, last_name, email, pass,registration_date) VALUES ('$fn','$ln','$e',SHA1('$p'),now())";
$r=@mysqli_query ($dbc ,$q);
if($r){
echo '

Thank you !

you are now registered.

';
}else{
echo "

system error

you could not bi registered due to a system error . We apolagize for any inconvenience. mysqli_error:.mysqli_error($dbc).
Query:.$q.

";
}
mysqli_close($dbc);
include('footer.html');
exit();
}else{
echo"

error!

the following error occurrde :

" ;
foreach($error as $key =>$msg){
echo "the error at $key is $msg
";
}
echo"

please try again

";
} #错误显示
 
 
}
?>

Register

 

please do it

 

 

First_name:

 

Last_name:

 

Email Address:

 

Password: