Compare user input to flat file data

Posted on 16th Feb 2014 by admin

Help...Am a complete newbie to programming so my code is prolly quite long. Am trying to verify a users details entered into a login form against details stored in an existing flat file.
No matter what I input, I get "not registered", even if it does match.
What have I done wrong? I have spent 3 LOOng afternoons trying to nut this out..now am going nuts....

<?php

if ($_POST['submit']=="submit")
{
$errormessage = "";
if (empty($_POST['userName']) ||empty($_POST['password']))
{
$errormessage = "<p>Please enter a user name and password</p>";
}
else
{
$userName=trim($_POST['userName']);
$password=trim($_POST['password']);

// check user name and password
$nameFlag=false;
$passwordFlag=false;

$fp = fopen($_SERVER['DOCUMENT_ROOT']."/toys/users.txt","r" );

while (!feof($fp))
{
$line=fgets($fp,100);

($userName== $line? $nameFlag=true : $nameFlag=false);

($password==$line? $passwordFlag=true : $passwordFlag=false);

}

fclose($fp);


if($nameFlag && $passwordFlag==true)
{
$foundFlag= true;
}
else
{
$foundFlag=false;
}
($foundFlag==true?$welcome= "Welcome ".$userName." you are now logged in":$sorry= "Sorry you are not registered");

}


}


?>
// my html form below
<form method="post" action="<?=$_SERVER['PHP_SELF']?>" >
<fieldset class="outline">
<h3>Registered customers</h3>
<label>User Name:</label>
<input type="text" class="login" value="" name="userName" id="userName" />
<label>Password:</label>
<input type="text" class="login" value="" name="password" id="password"/>
<br />
<br />
<input type="submit" value="submit" name="submit" id="submit"/>
<br />
<?=$errormessage?>
<br />
</fieldset>
</form>