how to remove special characters

[eluser]Wondering Coder[/eluser]
hello to everyone

just would like to ask how to remove this: -, [], / or any special characters in my input

tried setting rules in validation using xss_clean but it still it save those character.

e.g input:
1111-1-1111 = must only save 111111111
2222/2/2222 = must only save 222222222
2222#222#22 = must only save 222222222

etc….