[2005] Help in Coding

I want to make functions easy to use. So for summarizing about the function I'm using

Code:

---

    ''' -----------------------------------------------------------------------------
    ''' <summary>
    '''
    ''' </summary>
    ''' <param name=""> </param>
    '''-----------------------------------------------------------------------------

---

I want to enable a feature for the function that if a variable say 'Var1' can take values from a list (val1,val2,val3,val4) than if user writes the function name it must display the list to choose the value from the list.

Like if we declare a variable bFlag of type Boolean and later when we write 'bFlag=' it automatically displays two options 'True and Flase' user just has to select one and no need to write whole string. Similarly in 'msgbox' after writing string when user presses ',' then a list is displayed to select one of the MsgBoxStyle from the list.
So I need to enable the user for similar cases when I've predefined set of values for some argument of the variable.

can anybody help me to enable this feature in the function call writing
:) .

I'd be interested in learning how to do this as well :) Always wanted to do it in the past but never got round to trying to actually do it