vb.net - Visual basic membership program using select case? -

vb.net - Visual basic membership program using select case? -

i writing programme asks user age , number of years have been member, trying through using select case. doesn't appear working, of ages fine if utilize checkbox veteran , should discount doesn't work. number of years have been fellow member doesn't alter price/ category, programme simple , i'm not sure why isn't working.

screen shot of program:http://gyazo.com/ebab66526068f4c81a30c624aada7f7c

code:

public class form1 private sub btncalc_click(byval sender system.object, byval e system.eventargs) handles btncalc.click dim x integer dim y integer x = val(txtage.text) y = val(txtyears.text) select case x case <= 18 lblprice.text = ("£60") lblcategory.text = ("junior") case 19 49 lblprice.text = ("£120") lblcategory.text = ("senior") case >= 50 lblprice.text = ("£80") lblcategory.text = ("over 50") case chkveteran.checked lblprice.text = ("£50") case <= 18 , y >= 2 lblprice.text = ("£40") lblcategory.text = ("2 year junior discount") case >= 50 , y >= 10 lblprice.text = ("£90") lblcategory.text = ("10 year senior discount") case chkveteran.checked , y >= 10 lblprice.text = ("£20") lblcategory.text = ("10 year veteran discount") end select end sub

end class

only 1 case block can run, seem expecting multiple blocks run. consider subset of clauses:

case <= 18 lblprice.text = ("£60") lblcategory.text = ("junior") case chkveteran.checked lblprice.text = ("£50") case <= 18 , y >= 2 lblprice.text = ("£40") lblcategory.text = ("2 year junior discount")

if x less or equal 18 first case block run. others ignored, regardless of state of chkveteran or y. series of case clauses needs mutually-exclusive in order logic create sense. example:

case <= 18 , y < 2 lblprice.text = ("£60") lblcategory.text = ("junior") case <= 18 , y >= 2 lblprice.text = ("£40") lblcategory.text = ("2 year junior discount")

these 2 clauses exclusive, 1 of them can apply @ time. each clause checked in order first lastly , first 1 matches execute. should set logic such first clause matches should only clause matches.

edit: in response separate comment thread...

you defined logic as:

a sports club has 3 categories of membership charge. juniors (ages 18) pay £60 per year, seniors (19-49) pay £120 , veterans (50 , over) pay £80. juniors have been fellow member 2 years or more £20 reduction. seniors , veterans have been members 10 years or more £30 reduction.

that sounds me 2 conditional sequences. first 1 define base of operations rate, this:

if age < 19 rate = 60 else if age < 50 rate = 120 else rate = 80 end if

the sec 1 define discount base of operations rate, this:

if age < 19 , tenure > 1 rate = rate - 20 else if age > 18 , tenure > 9 rate = rate - 30 end if

two separate conditional sequences, each checking exactly conditions explicitly defined in requirements. can farther refactor them create semantic meaning more clear. example, extract definitions of "junior, senior, , veteran" separate logic:

if isjunior(age) rate = 60 else if issenior(age) rate = 120 else if isveteran(age) rate = 80 end if

you can create functions each of those, like:

function isjunior(byval age integer) boolean homecoming age < 19 end function

this extracts details of implementation smaller helper functions , allows top-level logic expressed in semantic concepts rather implementation details, allowing overall look of logic match description given requirements much more clearly.

vb.net select