getting white screen after executing php code - php

Question

Hi I am working on a simple php registration. But everytime I am submitting the registration page, i am getting a blank screen, no error, no display.
The code in my php file is :
<?php
if($_SERVER['REQUEST_METHOD']=="POST"){
$IP = //my hostname
$dbuser = "my user id";
$conn = new mysqli_connect($IP, $dbuser, "","my databse name");
if(! $conn )
{
die('Could not connect: ' . mysqli_error());
}
$name = $_POST['name'];
$phone = $_POST['phone'];
$email = $_POST['email'];
$pass1 = $_POST['pass1'];
$pass2 = $_POST['pass2'];
$address = $_POST['address'];
$query = "SELECT email FROM user where email='".$email."'";
$result = mysqli_query($conn,$query);
$numResults = mysqli_num_rows($result);
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) // Validate email address
{
$message = "Invalid email address please type a valid email!!";
}
elseif($numResults>=1)
{
$message = $email." Email already exist!!";
}
else
{
mysqli_query("(insert into user(name,phone_number, email,pass1, pass2, address) values
('".$name."','".$phone."', '".$email."', '".$pass1."','".$pass2."','".$address."')");
echo $message = "Signup Sucessfully!!";
}
mysqli_close($conn);
}
print_r(error_get_last());
?>
there is no issue in establishing connection as i am using this connection method in other pages and they are working fine. Also i should specify that currently i am working on cloud 9 and my mysql database is on cloud9 itself.
please help me in undersstanding the trouble.

Answer 1

You say your line 42 has the insert query. I suppose you mean this query:
mysqli_query("(insert into user(name,phone_number, email,pass1, pass2, address) values
('".$name."','".$phone."', '".$email."', '".$pass1."','".$pass2."','".$address."')");
As your error says "2 parameters expected", you are missing here your connection parameter. You should have this:
mysqli_query($conn, "(insert into user(name,phone_number, email,pass1, pass2, address) values
('".$name."','".$phone."', '".$email."', '".$pass1."','".$pass2."','".$address."')");

Answer 2

Put this in on the first line of your script
ini_set('display_errors', '1');
This will then display the errors on the page and you will be able to see what is going wrong.
Also rather than the IP address try "localhost"
$conn = new mysqli_connect("localhost", $dbuser, "","my databse name");
If the database is on the same machine this may solve your problem.

Answer 3

Also your code is incredibly unsafe and will suffer from SQL injection. Please consider the following lines:
$email = $_POST['email'];
$query = "SELECT email FROM user where email='".$email."'";
Basically you put whatever the user is passing into your SQL statement. What if he enters "' OR 1; DROP TABLE user". You would lose all your data.
Please read about SQL injection and use PDO:
http://en.wikipedia.org/wiki/SQL_injection
http://php.net/manual/fr/book.pdo.php