If empty help and check if user exists.

[Anders Moen]

As the topic says, I wanna make a message if not all required fields are written in. And I also wanna make so they can't register the same user twice.If anyone can help, here's the code:

<?php if($_POST['submit']) {$con = mysql_connect("localhost","username","password");mysql_select_db ("database_name",$con) or die ("ERROR!");if(empty($bruker)) { // If I use || or OR and put on more fields there, I just get an error message :S (I can't say it cause I don't have it right now). But I want all required fields to have their own "personal" message if they haven't been filled out. die ('Fill in all required fields.');}$bruker = htmlspecialchars(strip_tags($_POST['bruker']));$pass = htmlspecialchars(strip_tags($_POST['pass'])); $mail = htmlspecialchars(strip_tags($_POST['mail']));$age = htmlspecialchars(strip_tags($_POST['age']));$interests = htmlspecialchars(strip_tags($_POST['interests']));$query = mysql_query("INSERT INTO Members (bruker, pass, mail, age, interests) VALUES ('$bruker', '$pass', '$mail', '$age', '$interests')");}if($query){ echo("<table><tr><td><strong>Username</strong></td><td>$bruker</td></tr><tr><td><strong>Mail</strong></td><td>$mail</td></tr><tr><td><strong>Age</strong></strong></td><td>$age</td></tr><tr><td><strong>Interests</strong></td><td>$interests</td></tr></table>"); } else { echo(" <form action=\"\" method=\"post\"> <p>Username:<br /><input type=\"text\" size=\"40\" name=\"bruker\" /></p><p>Password:<br /><input type=\"password\" size=\"40\" name=\"pass\" /></p> <p>E-mail:<br /><input type=\"text\" size=\"40\" name=\"mail\" /></p><p>Age:<br /><input type=\"text\" size=\"40\" name=\"age\" /></p><p>Interests<br /><textarea rows=\"3\" name=\"interests\"></textarea></p><p><input type=\"submit\" value=\"Register \" name=\"submit\" onmouseover=\"validate()\" /></p> </form> "); }?>

For the check if user exists, the username field in database, is called "bruker" just so you know

[jesh]

Are you saying that the following produces errors?:

if(empty($bruker) || empty($pass) || empty($mail))

As for checking if a username already exists, you might set the username column as an identity column which doesn't allow duplicates. Then, when you try to INSERT a record with a username that already exists in the database, the INSERT will fail. You could check after you attempt the INSERT whether an error was returned or you might be able to check how many records were affected - a successful INSERT would have affected 1 record wereas a failed INSERT would be 0 records. Alternatively, you could run a SELECT against the table for a record with a particular username. If the SELECT returns nothing, then you know that there isn't already a record in the database with that username and you can proceed with the INSERT.If you were using stored procedures, you could probably take care of this with one call to the database.

[Anders Moen]

Thanks :)The Master will check out the check if user exists. I can't be bothered cause I'm thirsty and tired.

[MrAdam]

by the way, you can make it much easier for yourself if you use:

echo '<form action="" method="post">';

instead of:

echo "<form action=\"\" method=\"post\">";

[Anders Moen]

Yeah, I know but I never do it because I'm used to normally make "<form action='' method='post'>";

[Mr_CHISOL]

Instead of using die() you can use one of these:

header("Location: index.php?user=$bruker&interest=$interest&...&msg=Fill in all fields");..header("Location: index.php?user=$bruker&interest=$interest&...&msg=That username is taken");...// Above the form putif ($_GET['msg']) {	  echo '<span style="color #00F">'.$_GET['msg']."</span><br />\n";}// In the form use (replace field with the fieldname<input type="text" name="field" value="<?php echo $_POST['field'];?>" />

or yoy can use this (it looks better than die, but not as good as the one above)

echo '<script type="text/javascript">'echo 'alert("Fill in all fields"); history.back();"echo '</script>';exit();...echo '<script type="text/javascript">'echo 'alert("The username is taken"); history.back();"echo '</script>';exit();

[Anders Moen]

Okay. I'll try it next time I make a script