InfoPath Dev

We are building a layered solution where we will have a "Domain layer" where we have all the business logic etc.

Is there any design patterns how to use this logic from InfoPath so when a rule change in the Domain layer it automaticly is
used by the InfoPath form..

 Compare Enterprise lib Validation Application Block   ...Quote

"Any application that accepts input either from users or from other systems must ensure that the information is valid in terms of some set of rules that you specify. For example, when processing an order, you may need to check that a customer's phone number has the correct number of digits, or that a date falls within a particular range. In addition, if the validation fails, you may need to send an error message that explains what is wrong.

The Enterprise Library Validation Application Block provides a library of classes, called validators, that supplies the code for validating .NET Framework data types. For example, one validator checks for null strings and another validator checks that a number falls within a specified range."

 The cool thing would be to use this from InfoPath

I have not tried this or evaluated it but I work with large enterprise solutions all the time.

If you would like to discuss best practices and architecture for large scale, InfoPath form solutions send me an email.

For me best practice is regarding Business logic

1. Separate presentation and business logic in different layers
   http://msdn2.microsoft.com/en-us/library/aa581779.aspx
   
2. "Reuse" Validation and Business rules ==>
   you write it once and it is used in ASP.NET, services etc.
   
   Exampel is the Enterprise Lib Validation Block where you have a facade
   
   eg.  ValidationResults r = Validation.Validate<Customer>(myCustomer);
           if (!r.IsValid)
           {
               throw new InvalidOperationException("Validation error found.");
           }
   
   means that I call the Validation facade to validate my customer ==> all the validation is in one place in the code
   
   
   
   see also http://www.davidhayden.com/blog/dave/archive/2006/12/23/ValidationApplicationBlockEnterpriseLibrary3PartI.aspx
   

So is this what we want!?!?

How to do it in InfoPath?!?!

My 4 days playing with the product tells me:

that maybe this should be done using events ?!?!
see
Using the Events Manager of the InfoPath Hosted Control

Found this approach which from an user perspective is not to preffer as you need to do a round trip to the server. The validation should I think be in the client to give a good user experience...

"On submittal, send the data to a Web service and perform all possible validations on the server side. For example, if you have a condition that employees are not to submit expense reports greater than $100 without specifying an approver, have the Web service process the dataset and verify that the condition is satisfied before the data is submitted."
http://technet.microsoft.com/en-us/library/cc262895.aspx

Are you using browser based forms or the InfoPath client?

Typically we use web services to off-load some of the processing and also to standardize our forms.

I would be interested in learning your requirements and the scope of what you are wanting to accomplish. It sounds interesting.

We have not selected how to create forms yet. Infopath could be one way forward but it looks like we should implement more than 60 processes for external users to initiate ==> means that intenally we will have much more so to have the business rules at one place
could be a time saver and a maintenance saver...

 I think the Infopath client for internal users could be a way forward but for external I feel webbased forms could be a license cost that the project not would like to take (Forms Services on intranet...)

The big advantage of using InfoPath for development is that normal users can then design and manage their own forms without dependencies on developers.  Leveraging the built in features each successive from can leverage a lot of the last one.  Most of what I do is codeless so it can be reused and adapted for multiple users.  Publishing an ddeployment is very slick too.

You would have to consider your TCO to see what the best medium is for your electronic data collection and processing.

TCO is important and easy to create the next form....

MOSS will be a key coimponent and I like what I have seen with Document Information panels etc...

It would be nice to see where the next version of InfoPath will go... I was at ODC2008 in SF and didn't see any
stories about InfoPath and the future...

I will be at the MVP conference next week and meeting with the InfoPath team so maybe I will have some information after that which I can disclose.

Cool interesting areas I can see after 4 days digging in the product is

 1) Support for more fancy UI things like adding Ajax, Silverlight or WPF components, compare Silverlight for Sharepoint...
 2) The Business logic concept
 3) Future: Will InfoPath meet Entity Framework or where will InfoPath be in the Astoria(Oslo concept)

Also if we get better integration with WCF is of interest...