Here a and b were flow field values. Now here in Form B i will assign a button(release) if i click this button the value in Form A should be get changed. i.e c value(a-b) should be calculated.
Correct me if my understanding is wrong. If you click a button in form B, form A should be opened and in the C text box, the calculated value should be displayed?
Kindly check the attachment. This would help you. Run the form 1 and provide your inputs. 2nd form will be opened which displays the calculated value. I got this from mibuso and you can find some more discussion also in mibuso