This code creates the form of registration fields.It
prevents the users to use the nicknames which are
inside the code: var blacklist=new Array
("hacker","fuck","admin","moderator"); Thus the
words like hacker,admin etc will not be allowed to
register through this form.You can use more words
in the blacklist.This code needs to be added inside
a html code element in a file.

<form onsubmit="checknick();" action="main.php?id=reg&ses=KrAslAo98nrtdNMOXglj7n2DTU9" method="post" > <div class="center"> Nickname(max 10 characters): <br/> <input id="username" name="nick" maxlength="10" value="" onchange="checknick();" /> <br/> Password(minimum 6 symbols): <br/> <input name="pass" maxlength="32" value=""/> <br/>Repeat password:<br/> <input name="re_pass" maxlength="32" value=""/> <br/> E-mail: <br/> <input name="email" maxlength="100" value=""/> <br/> Gender: <br/> <select name="sex"> <option value="1"> Male </option> <option value="2"> Female </option> </select> <br/> <img src="users-captcha.php?52ceb232b8746" alt="Captcha"/> <br/> Enter code from the image above: <br/> <input name="captcha" maxlength="6"/> <br/> <br/> <input type="submit" value="Register"/> </div> </form> <script> function checknick() { var blacklist=new Array("hacker","fuck","admin","moderator"); var uname=document.getElementById('username').value; for(var i=0;i<blacklist.length; i++) { if(uname.length>10) { document.getElementById('username').value=""; alert("Maximum 10 characters are allowed in nickname"); } if(uname.indexOf(blacklist[i])!=-1) { document.getElementById('username').value=""; alert("You can not use this nick"); return; } } } </script> <!--Code Copyright:G1Forum.Wap.Sh-->

NOTE: The words used inside the blacklist are very
sensitive.
For example: as the word 'admin' is blacklisted so
all the nick which have the word 'admin' inside it
(e.g. preadmin,admins,adminkiller) all will not be
allowed to register.