.net - For Condition VB.NET vs C# -

c#:

static class module1 {          public static void main()     {             (index = 1; index <= getcount(); index++) {             console.writeline("for {0}", index);         }         console.readkey();     }      public static int getcount()     {         console.writeline("getcount");         return 10;     } } 

result (c# rechecks condition):

getcount 1 getcount 2 getcount 3 getcount 4 getcount 5 getcount 6 getcount 7 getcount 8 getcount 9 getcount 10 getcount 

vb.net

module module1       sub main()     index = 1 getcount()       console.writeline("for {0}", index)     next     console.readkey()   end sub    public function getcount() integer     console.writeline("getcount")     return 10   end function end module 

result (vb.net not recheck condition):

getcount 1 2 3 4 5 6 7 8 9 10 

a) why doesn't vb.net respect "rule" of recheck condition on each iteration?
b) is there way force vb re-check condition?

c# , vb.net different languages, , similar keywords can have different semantics.

from the docs for ... next (my emphasis) :

when for...next loop starts, visual basic evaluates start, end, , step. this time evaluates these values.

from section 8.8.3 of c# specification (ditto):

when , if control reaches end point of embedded statement (possibly execution of continue statement), expressions of for-iterator, if any, evaluated in sequence, , iteration performed, starting evaluation of for-condition in step above.

if want force condition checked every time, vb.net offers extremely flexible ... loop can have while or until condition, operating @ start or end of loop. statement, loop condition is evaluated every time round.