Validation of a Address String in webdynpro

Hi experts

I have some problem in the validation of the Address field of data type String

The user is permitted to enter alphabet and the numbers but not special characters except '-' and '/'. I should not allow the user to enter any special characters like @,!,#,$,%,^,&,*,square braces,paranthesis like this.I should validate when ever a user enters a special characters of that type and throw an error message.Can you please any one can give the guide lines or code snippet which gives the remedy for my problem.

Thanks and Regards

Kalyan