Parse only the first 8 characters

[help_needed]

Hi,

I was wondering if someone can give me a hand.

If I submit a form (textbox) with the following:

abcdefghijklm

I'd like to use only the first 8 characters
abcdefgh (ijklm) should be eliminated.

Also, if they entered 123abcdefghijklm, it should be abcde123 (fghijklm) should be deleted.

What function would I use?

Thanks,

[jonno946]

http://uk2.php.net/manual/en/function.substr.php