php总是给出相同的响应

Question

my php script always gives the same respone. i'm trying to make a login Formular for Android.

maybe some one of you know why:

<?php
$con=mysqli_connect("localhost","root","","my_db");
//echo "Welcome, I am connecting Android to PHP, MySQL";

if (mysqli_connect_errno($con))
{
   //echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$username = $_POST['username'];
$password = $_POST['password'];



$result = mysqli_query($con,"SELECT Username FROM user where     Username='$username' and Password='$password'");



$flag['code'] =0;

if($result)
{
    $flag['code']=1;


} else {

    $flag['code'] = 0;

}

print(json_encode($flag));
//echo json_encode($flag)


mysqli_close($con);
?>

it always Prints Code:1 i hope some one know why this happens.

Answer 1

You do not check the result. You are just checking if it is non null. By the way you should handle a connection problem too.

I would modify your check to:

if(mysqli_num_rows($result) == 1) {
    $flag['code'] = 1;
} else {
    $flag['code'] = 0;
}

This will check if you got one result which means that you got a working login.

Please keep in mind to hash your passwords. Even within development you should keep passwords save.