Creating an account using Javascript

Question

Is it good to use Javascript to create an account or is it subject to security risks? If everything is ok, I should be able to display some errors if the username or email address already exists.

eg.

JavaScript:

function createAccount() {
   var new_user = $('#new-username').val();
   var new_pass = $('#new-password').val();
   var confirm_pass = $('#confirm-password').val();
   var new_email = $('#new-email').val();
   $.post('createaccount.php', {
       new_user: new_user,
       new_pass: new_pass,
       confirm_pass: confirm_pass,
       new_email: new_email
   });
}

createaccount.php:

$new_username = mysqli_real_escape_string($conn,$_POST['new_user']);
$new_password = mysqli_real_escape_string($conn,$_POST['new_pass']);
$new_email = mysqli_real_escape_string($conn,$_POST['new_email']);
$confirm_password = mysqli_real_escape_string($conn,$_POST['confirm_pass']);

$query = mysqli_query($conn,"SELECT * FROM users WHERE username='$new_username'");
$numrows = mysqli_num_rows($query);
$query2 = mysqli_query($conn,"SELECT * FROM users WHERE email='$new_email'");
$numrows2 = mysqli_num_rows($query2);

...

echo json_encode(array('numrows'=>$numrows,'numrows2'=>$numrows2));

I need to be able to use numrows, and numrows2once with $ .getJSON, to prevent some errors (such as user name already exists, or e-mail address is already in use). Any way to do this?

Answer 1

HTTP requests sent from Javascript code are no more or less secure than HTTP requests sent from HTML forms.

Answer 2

, PHP, , , Javascript, .

Answer 3

. . , , . SSL , javascript . , , , . NSA . Javascript , . Google "javascript ", , . . . , .