I need to manipulate with the week number of the year. I have a situation like... I get the start date and the days (multiple days) of the week like Monday & Friday from the user and need to perform the action. Then from then on every alternate week I need to perform the same action. Hope am clear.

Now what I am planning to do is... I want to have a integer variable and store the week number of the start date week to that variable. And then by manipulating with week numbers I can perform the actions. Now HOW DO I GET the week number stored to that integer variable. Please guide / help me. Thank you.

Any alternate thoughts / suggestion to handle this situation are welcome.
My environment is VS2005 / SQL / VB / Windowsapp.