Yeah, 200MB might be a bit much over COM. How do you plan to transport the data across COM? XML? How much data will you be sending from .NET back to VFP? I can tell you CursorToXML() is fast, but with 200MB of data, XMLToCursor() performance will be unacceptable. And that's just the VFP side. You should run some tests.

If the 200MB query is relatively simple, I would pull that in with pure .NET code. Then send small chunks of data back to VFP for processing, taking advantage of your more complex existing code.

>We are using WinForms with VB.
>
>We need to pass +/- 200MB of table data to .Net UI controls and to get some table data back from those controls into VFP.
>Would it be better to :
>A) Host all UI Controls in a WinForm and just pass table data to and fro from VFP and we would call the Winform from VFP and EventBind etc (This is our preference)
> or
>B) Host the .Net UI controls on a VFP form and access the .Net Controls from within VFP ?
>
>We have never done ComInterop before - what is the performace like especially when passing large amounts of data such at 200MB ?
>
>Thanks for all the replies posted for far
>
>>But you don't need the VB interop toolkit for that, at least not to pass and receive data from a .net dll in VFP or fire events in VFP from .net. We do that now via com interop...
>
>>>The VB Interop Toolkit definately works with VFP. But you don't need it for ActiveX controls as they "just work" on a VFP form. What the toolkit does is allow you to call VFP code from .NET and vice-versa and even have events in one environment fire code in the other.
>>>>
>>>>Hi Jared,
>>>>
>>>>I have not used the VB Interop Toolkit, but my understanding is that it is supposed to work with VFP. If you're wanting to put .NET components on a VFP form (like an ActiveX control), then I think it is your only option. Otherwise, I would steer you towards wwDotNetBridge, which gives you more complete access to the .NET framework without COM wrappers. I believe it will let you open a .NET form in VFP, but you'll want to double-check on that:
>>>>
>>>>http://www.west-wind.com/webconnection/wwClient_docs/_24n1cfw3a.htm
>>>>http://www.west-wind.com/wwClientTools.asp
>>>>
>>>>As Tracy said, you could make .NET the host environment for your UI and put VFP code in a COM object. That may be a better choice if you'll be rewriting your entire UI at once. You can host a VFP form in .NET using the SetParent() API, but that's kind of a hack. It depends on who you want to do the driving.
>>>
>>>By the way, what will you be using for the new UI: Winforms, WPF, or SilverLight?