validate User problem

[columbo1977]

Good Evening

I have created a server behaviour in Dreamweaver to check if a username exists when someone registers at the site.

When i click submit i get the following errors?

Warning: mysql_select_db(): supplied argument is not a valid MySQL-Link resource in c:\webserver\phpdev5\

http://www\ccc_website\registration.php

on line 8

Warning: mysql_query(): supplied argument is not a valid MySQL-Link resource in c:\webserver\phpdev5\

http://www\ccc_website\registration.php

on line 9

the code for the checking is below

<?php
// *** Redirect if username exists
$MM_flag="MM_insert";
if (isset($_POST[$MM_flag])) {
$MM_dupKeyRedirect="denied_u.html";
$loginUsername = $_POST['username'];
$LoginRS__query = "SELECT Username FROM users WHERE Username='" . $loginUsername . "'";
mysql_select_db($database_null, $null);
$LoginRS=mysql_query($LoginRS__query, $null) or die(mysql_error());
$loginFoundUser = mysql_num_rows($LoginRS);

//if there is a row in the database, the username was found - can not add the requested username
if($loginFoundUser){
$MM_qsChar = "?";
//append the username to the redirect page
if (substr_count($MM_dupKeyRedirect,"?") >=1) $MM_qsChar = "&";
$MM_dupKeyRedirect = $MM_dupKeyRedirect . $MM_qsChar ."requsername=".$loginUsername;
header ("Location: $MM_dupKeyRedirect");
exit;
}
}

Can anyone help as to why the errors come up.

Cheers

Columbo1977

 

[vacunita]

I believe its complaining about the parameters you are passing to the [blue]mysql_select_db[/blue] function either

$database_null, or $null, does not contain the correct information.

mysql_select_db
Description
bool mysql_select_db ( string database_name [, resource link_identifier] )

Sets the current active database on the server that's associated with the specified link identifier. Every subsequent call to mysql_query() will be made on the active database.
Parameters

database_name

The name of the database that is to be selected.
link_identifier

The MySQL connection. If the link identifier is not specified, the last link opened by mysql_connect() is assumed. If no such link is found, it will try to create one as if mysql_connect() was called with no arguments. If by chance no connection is found or established, an E_WARNING level warning is generated.[/red]

Make sure there is a call to mysql_connect before mysql_select_db, and that you pass the correct parametrs to the function.

----------------------------------
Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.

 

[columbo1977]

Situation has changed, please see code below.

<?php require_once('Connections/DB.php'); ?><?php
// *** Redirect if username exists
$MM_flag="MM_insert";
if (isset($_POST[$MM_flag])) {
$MM_dupKeyRedirect="denied_u.html";
$loginUsername = $_POST['username'];
$LoginRS__query = "SELECT Username FROM users WHERE Username='" . $loginUsername . "'";
$conn = mysql_connect('127.0.0.1','root','');
mysql_select_db($database_DB, $conn);
$LoginRS=mysql_query($LoginRS__query, $conn) or die(mysql_error());
$loginFoundUser = mysql_num_rows($LoginRS);
//if there is a row in the database, the username was found - can not add the requested username
if($loginFoundUser){
$MM_qsChar = "?";
//append the username to the redirect page
if (substr_count($MM_dupKeyRedirect,"?") >=1) $MM_qsChar = "&";
$MM_dupKeyRedirect = $MM_dupKeyRedirect . $MM_qsChar ."requsername=".$loginUsername;
header ("Location: $MM_dupKeyRedirect"); <----------------------------------------------------Line18
exit;
}
}

and the error mesage i now get is

Warning: Cannot add header information - headers already sent by (output started at c:\webserver\phpdev5\

http://www\ccc_website\registration.php:1)

in c:\webserver\phpdev5\

http://www\ccc_website\registration.php

on line 18

Does anyone know why?

 

[Vragabond]

Check for any output (either html before the opening <?php bracket, a space or enter before it, or print or echo statements in the file and all included files) before the header call. Header needs to happen before any other output.

 

[columbo1977]

Excellent, thanks for that, I had a space at the beginning.
All working ok now

Cheers

Columbo