error checking on guestbook form

[mike08]

ive used this error checking methods for email and username in my registration form

i want to use the same method but with an added one for (comments) as building a guestbook

can someone show me what to do please for checking this as am stuck, cheers.

//Check for an email address. 
if (eregi ("^[[:alnum:]][a-z0-9_.-]*@[a-z0-9.-]+\.[a-z]{2,4}$",stripslashes(trim($_POST['email'])))) { 
   $e = escape_data($_POST['email']); 

} else { 

   $e = FALSE; 
   echo '<p><font color="red" size"+1">Please enter a valid email address!</font></p>'; 
} 

//Check for a username. 
if (eregi ("^[[:alnum:]_]{4,20}$", stripslashes(trim($_POST['username'])))) { 
   $u = escape_data($_POST['username']); 
} else { 
   $u = FALSE; 
   echo '<p><font color ="red" size="+1">Please enter a valid username!</font></p>'; 
} 

[Natty_Dreadlock]

hi, not a problem at all, insert the following code and use $comment to get the comment (in your guestbook form, include a textbox named comment):

//Check for a username. 
if (trim($_POST['comment'])){  

   $comment = escape_data($_POST['comment']);  

} else {  

   $comment = FALSE;  

   echo '<p><font color ="red" size="+1">Please enter comment!</font></p>';  

}

hth & next time check docu since it's really a very basic problem...