understanding this code...

Dutch_MaFia-boy

I am trying to figure out what is going on in the following code. The link to what I am referring to will be displayed below the code.

if ( $num != 0 ) { 

     // A matching row was found - the user is authenticated. 

     $auth = true; 

 } 

 } 

 if ( ! $auth ) { 

 header( 'WWW-Authenticate: Basic realm="Private"' ); 
 header( 'HTTP/1.0 401 Unauthorized' ); 
 echo 'Authorization Required.'; 
 exit; 

 } else { 

 echo '<P>You are authorized!</P>'; 
 } 

 ?> 

[url]http://www.zend.com/zend/tut/authentication.php#Heading11[/url]

I am curious to know what the ALL the code actually means . ie) $num != 0 - What does the ! symbol mean?  It would problay be best to comments about each line or maybe provide a helpful link to additional info.

Thanks.

tekky

Read the manual

Simple things like this are easily discovered by reading the online documentation or opening a book

Dutch_MaFia-boy

My problem is that I am getting a parse error on line 69 - if ($num ! = 0 ) {

Can anyone see why this is happening??

<?php

## Apache server fix ##
if (isset($_SERVER['PHP_AUTH_USER']) && !isset($_ENV['REMOTE_USER']))
   $_ENV['REMOTE_USER'] = $_SERVER['PHP_AUTH_USER'];
if (isset($_SERVER['AUTH_PASSWORD']) && !isset($_ENV['PHP_AUTH_PW']))
   $_ENV['PHP_AUTH_PW'] = $_SERVER['AUTH_PASSWORD'];

include("guestcon.php");
?>

<html>
<head><title>Login</title></head>
<body>

<h2Please login</h2>
<form name=login>
<table>

<tr height=30 valign=top>
<td align=right><b>Username :</b></td>
<td>
    <input type="text" name="usernameField">
</td>
</tr>


<tr height=30 valign=top>
<td align=right><b>Password :</b></td>
<td>
    <input type="password" name="passwordField">
</td>
</tr>

</table>

<input type=submit name=Submit value="Submit">
<input type=reset name=reset value="Reset">
</form>

<?php

// Assume user is not authenticated
$auth = false; 

//Returns TRUE if $PHP_AUTH_USER and $PHP_AUTH_PW exists; FALSE otherwise. 
if (isset ($PHP_AUTH_USER ) && isset($PHP_AUTH_PW)) {

$PHP_AUTH_USER = addslashes($PHP_AUTH_USER);
$PHP_AUTH_PW = md5($PHP_AUTH_PW);


// Select database on MySQL server 
mysql_select_db($db)
or die("Couldn't open $db: ".mysql_error());

// Formulate the query 
$sql = "SELECT * FROM login WHERE username='$PHP_AUTH_USER' and password='$PHP_AUTH_PW'";

// Execute the query and put results in $result 
$result = mysql_query( $sql )  

     or die ( 'Unable to execute query.' ); 

// Get number of rows in $result.
$num = mysql_numrows($result);
print "There are $numrows rows.";

//TRUE if $num is not equal to 0.
if ($num ! = 0 ) { 

// A matching row was found - the user is authenticated. 

  $auth = true; 
  }
}   

if ( ! $auth ) { 

 header( 'WWW-Authenticate: Basic realm="Private"' ); 
 header( 'HTTP/1.0 401 Unauthorized' ); 
 echo 'Authorization Required.'; 
 exit; 

 } else { 

 echo '<P>You are authorized!</P>'; 
 } 

?>

tekky

Originally posted by tekky
Read the manual

Simple things like this are easily discovered by reading the online documentation or opening a book

If you would have looked at the page I gave you the link to, you would have seen that the operator is:

!= not ! =

Dutch_MaFia-boy

Yes, I kinda figured that out. I learn by seeing examples.....

Its still not working though - I even separted the php and html form onto sepate pages, and it still parse errors out on:

if ($auth != true) {

it looks right, but its not working! This kinda stuff is real discouraging to a newbie!

notice how I changed it around...

Adrian

tekky

if ($auth) { //true }
if (!$auth) { //false }

php doesnt have a boolean global like TRUE/FALSE in VB (if it does I've never seen it used....

anything that is 0 would be false in the above statements, anything above 1 would be true (if the variable wasnt set... it would be false also...)