data validations

I need help on how to validate these data in visual basic.net:


1. the password must not be same as employee ID and must contain 4-6 characters

2. email must ba a valid one

3. name and address fields cannot be left blank

4. maxium score must be postive number between 1 and 100

5. number of students must be postive integer


Assuming password, email, name and address, max score, and number of students are textboxes. If the each rule are broken then a messagebox will appear. Thank you.