|
dev
newsgroups
|
|||||||||||||||||||||||
|
|||||||||||||||||||||||
constraint programmingHow can I include contraints in VB.NET (Windows Forms, 2.0), using Objects with Propertys? I need several property's be recalculated when others change, but not in a straightforward way: When A is changed, B has to change, but when B changes, A has to change (or C or ...). Untill now I added routines in the Set-Property that calculated the other Property, but I'm loosing the overview, and I would have referred to have all this rules centrally placed. Also, I'm kind of affraid of endless loops: A changes B, B changes A, which changed B again etc etc... Is there a way to do some kind of constraint programming in VB.NET? Or how should I implement such a thing the best way? I need constraints like this: - When the Currency changes, the AmountNewCurrency must be automaticly changed to AmountOldCurrency * CurrencyRate but: When the user changes the in the TextBox the AmountNewCurrency, the AmountOldCurrency must be changed too (AmountNewCurrency / CurrencyRate). - Another one: TotalBuyPrice = the total Price we pay for all the Articles TotalSellPrice = The total Price at which we sell the Articles Percentage: the percentage we add to the TotalBuyPrice to have a sudden TotalSellPrice. -> Is Percentage is changed, TotalSellPrice must be changed (and the ArticleSellPrice accordingly). but: -> When the TotalSellPrice is changed, the percentage has to be calculated automaticly, and the ArticleSellPrice of each article has to be changed proportionally - and many many more... Any help would be really appreciated, Thansk a lot in advance, Pieter I agree with Phil... update everything from each input to the function.
IOW, have a 'recalculate_page' method that calculates every function, from currency to total price. Then, when the user changes any of the inputs, from locale to quantity, whatever, call 'recalculate_page'. -- Show quote--- Nick Malik [Microsoft] MCSD, CFPS, Certified Scrummaster http://blogs.msdn.com/nickmalik Disclaimer: Opinions expressed in this forum are my own, and not representative of my employer. I do not answer questions on behalf of my employer. I'm just a programmer helping programmers. -- "Pieter" <pieterNOSPAMcoucke@hotmail.com> wrote in message news:O12ZPlHQHHA.4424@TK2MSFTNGP06.phx.gbl... > Hi, > > How can I include contraints in VB.NET (Windows Forms, 2.0), using Objects > with Propertys? > > I need several property's be recalculated when others change, but not in a > straightforward way: When A is changed, B has to change, but when B > changes, A has to change (or C or ...). > Untill now I added routines in the Set-Property that calculated the other > Property, but I'm loosing the overview, and I would have referred to have > all this rules centrally placed. Also, I'm kind of affraid of endless > loops: A changes B, B changes A, which changed B again etc etc... > > Is there a way to do some kind of constraint programming in VB.NET? Or how > should I implement such a thing the best way? > > I need constraints like this: > - When the Currency changes, the AmountNewCurrency must be automaticly > changed to AmountOldCurrency * CurrencyRate > but: > When the user changes the in the TextBox the AmountNewCurrency, the > AmountOldCurrency must be changed too (AmountNewCurrency / CurrencyRate). > > - Another one: TotalBuyPrice = the total Price we pay for all the Articles > TotalSellPrice = The total Price at which we sell the Articles > Percentage: the percentage we add to the TotalBuyPrice to have a sudden > TotalSellPrice. > -> Is Percentage is changed, TotalSellPrice must be changed (and the > ArticleSellPrice accordingly). > but: > -> When the TotalSellPrice is changed, the percentage has to be > calculated automaticly, and the ArticleSellPrice of each article has to be > changed proportionally > > - and many many more... > > > Any help would be really appreciated, > > Thansk a lot in advance, > > Pieter > I agree with Phil... update everything from each input to the function.
IOW, have a 'recalculate_page' method that calculates every function, from currency to total price. Then, when the user changes any of the inputs, from locale to quantity, whatever, call 'recalculate_page'. -- Show quote--- Nick Malik [Microsoft] MCSD, CFPS, Certified Scrummaster http://blogs.msdn.com/nickmalik Disclaimer: Opinions expressed in this forum are my own, and not representative of my employer. I do not answer questions on behalf of my employer. I'm just a programmer helping programmers. -- "Pieter" <pieterNOSPAMcoucke@hotmail.com> wrote in message news:O12ZPlHQHHA.4424@TK2MSFTNGP06.phx.gbl... > Hi, > > How can I include contraints in VB.NET (Windows Forms, 2.0), using Objects > with Propertys? > > I need several property's be recalculated when others change, but not in a > straightforward way: When A is changed, B has to change, but when B > changes, A has to change (or C or ...). > Untill now I added routines in the Set-Property that calculated the other > Property, but I'm loosing the overview, and I would have referred to have > all this rules centrally placed. Also, I'm kind of affraid of endless > loops: A changes B, B changes A, which changed B again etc etc... > > Is there a way to do some kind of constraint programming in VB.NET? Or how > should I implement such a thing the best way? > > I need constraints like this: > - When the Currency changes, the AmountNewCurrency must be automaticly > changed to AmountOldCurrency * CurrencyRate > but: > When the user changes the in the TextBox the AmountNewCurrency, the > AmountOldCurrency must be changed too (AmountNewCurrency / CurrencyRate). > > - Another one: TotalBuyPrice = the total Price we pay for all the Articles > TotalSellPrice = The total Price at which we sell the Articles > Percentage: the percentage we add to the TotalBuyPrice to have a sudden > TotalSellPrice. > -> Is Percentage is changed, TotalSellPrice must be changed (and the > ArticleSellPrice accordingly). > but: > -> When the TotalSellPrice is changed, the percentage has to be > calculated automaticly, and the ArticleSellPrice of each article has to be > changed proportionally > > - and many many more... > > > Any help would be really appreciated, > > Thansk a lot in advance, > > Pieter >  |
|||||||||||||||||||||||
Other interesting topics