Changed mysql to mysqli and can't connect to database - mysqli

Question

I am not very experienced in this field so this is why I am seeking help.
I recently changed hosts and a script stopped working. After moving all files the new hosts said mysql is deprecated, so after doing a bit of search I decided to change mysql with mysqli and that deprecated error was gone. But now I get a new error (error select db). I think I must make adidtional changes to the script to connect mysqli. This is the file I have
<?php
class Model{
var $conn;
public function openDb($dbhost, $dbuser, $dbpass, $dbname, $conn)
{
//echo "Se creo la conexion ";
$conn = mysqli_connect($dbhost, $dbuser, $dbpass) or die('Error connecting to mysqli');
mysqli_select_db($dbname) or die('Error select db');
mysqli_query("SET NAMES utf8");
return $conn;
}
public function closeDb($conn)
{
mysqli_close($conn);
}
public function query($query)
{
if ($result = mysqli_query($query) or die("Error de Query: </br >" . mysqli_error()."<br/>".$query)) {
//if ($result = mysqli_query($query)) {
} else {
$result = false;
}
return $result;
}
function __construct()
{
$this->openDb(dbhost, dbuser, dbpass, dbname, $conn);
}
//insertGenerico con indedices asiciativos
function insertar($tabla, $datos)
{
$columnas = implode(", ", array_keys($datos));
$valores = implode(", ", $datos);
$query = "INSERT INTO $tabla
($columnas)
VALUES
(" . $valores . ")";
return $this -> query($query);
}
function insertarRelacionArray($tabla, $tablaRelacion, $datos)
{
foreach ($datos as $row) {
$query = "INSERT INTO $tabla
($tablaRelacion[0],$tablaRelacion[2])
VALUES
($tablaRelacion[1],$row)";
//echo '<br>'.$query;
$this -> query($query);
}
}
//getGenerico
function get($tabla, $where = false, $order = false)
{
$query = "SELECT *
FROM $tabla
$where
$order";
return $this -> query($query);
}
//deleteGenerico
function delete($tabla, $id, $idTag = false)
{
if($idTag==false)
$idTag = "id";
$query = "DELETE FROM $tabla
WHERE $idTag = $id";
return $this -> query($query);
}
//update generico
function update($tabla, $datos, $id, $idTag = false)
{
$columnas = array_keys($datos);
$SET = 'SET ';
$i = 0;
foreach ($datos as $key => $value) {
if (next($datos)) {
$SET .= "$key = $value ,";
} else {
$SET .= "$key = $value ";
}
}
if($idTag==false)
$idTag = "id";
$query = "UPDATE $tabla $SET WHERE $idTag = $id;";
return $this -> query($query);
}
}
?>

Answer 1

As described on http://php.net/manual/en/mysqli.select-db.php first parameter should be $link.
bool mysqli_select_db ( mysqli $link , string $dbname )
So change
mysqli_select_db($dbname) or die('Error select db');
to
mysqli_select_db($conn, $dbname) or die('Error select db');
and it should work.
I think that you need to return $conn in your _construct function too, or store it in the object ($this->conn = $conn) so you can use it again.
In addition (thanks to Ki Jéy) you should also update
mysql_query($query)
to
mysqli_query($conn, $query)
and
mysql_real_escape_string($string)
to
mysqli_real_escape_string ($conn, $string)