Right well, im using php for my alt community website and recently someone suggested that i should put something on so someone could check the username they imputed was already in use without having to submit the whole join request...

Im not sure how to do it, but i do have ideas on methods...
- use js to open up a winow with the url of index.php?page=checkusername&username=*what they inputed* and do the rest with php
- use js its self to check the database
but i dont know which is better and i dont no how to do either so please could some help me...?

thanks in advance xx

xx kieran xx

no choice really as clientside javascript can't actually access the database.

ah, i thought it possibly could. Ah well

Ive actualy had another poissble idea sinse...
make it so that js files are processed by the php thing :P then put every single username that is already taken into a js array... link the js file to the join script... and *somehow* make it so that you can click a link and the text appear below it saying if its been taken or not...

that would be possible BUT you will then expose every user name in the database in the client-side source.

Yea but thats nothing you couldnt find out anyway from searching, and its not like its passwords or something that should be kept secret...

But anyway, what would be the most effective way...?

usernames can be used with a SQL injection attack or a brute force/dictionary attack on weak passwords so could make your system vunerable.

Personally I have never bothered checking before a submit, I just collect all the other data in the form and present it back to the user and "flag" the missing items and/or show a message. In the case of usernames you can present some alternatives in the MSN Passport/Gmail/Googletalk style using the user input and some random numbers, if you ask for a first name and surname you can offer alternatives based on that input as well, couple that with a radio button to select one and away you go again.

i really dont wanna submit all the information cause that would involve me messing around with the back end of it lol im lazy atm :P

so how about i open a new window to a php file and the php check if its being used and if it is then display other options ... ? :P

so how do i do that it would need to open up index.php?page=misc&do=usercheck&user=*username inputed*&alt=*first name inputed* please help

I'll have a play and see what I come up with when I'm back at my own desk

thanks dude

You can write a PHP script that checks for the username, and returns a t/f value and use XMLHTTPRequest to get the variable before submitting the form. If the XMLHTTPRequest returns true, give the user an error, if false, then process the form. I'd put username checking in the processing script regardless, just in case someone doesn't have JS or bypasses it.