P3D v3 Any Microsoft .NET library to interface with P3D?

I need to interface to Prepar3D using C# and would like to know if there is any helper library that would use SimConnect or perhaps FSUIPC (Free).

I used to develop with a library called FSUIPClient.NET from Paul Henty for FSX but that relies exclusively on FSUIPC and I do not know if it works at all with P3D. I have been waiting to get my password reset from their forum but no luck so far.
There used to be a Managed SimConnect client for FSX and ESP maintained by a gentlemen who used to be on Aces team. Tim Gregson IIRC.

Maybe you can find it and use it, P3D should be backwards compatibile.


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Have you looked in the P3D SDK Core Utilities/SimConnect/Samples? There are samples for Client Event and for Managed Client Event for example. Also search this forum for C# relevant posts. I'm sure I remember posts about this, or contact rhumbaflappy via this forum - he actually knows things about this, which is more than I do.
@pfabian I tried the Beatles library from Tim Gregson some years ago but it appeared not to work anymore. If you look at his Beatles Blog his efforts stopped at a Beta 3 of his library back in 2009.

@hairyspin No I have not had the chance to look at it yet, I do not have access to the P3D SDK because I do not have a license yet and hoped to develop something prior to commiting to buying a license (I am unemployed).

I used successfully the FSUIPClient.Net library from Paul Henty (SimFlight forums, a subforum of Pete Dowson's FSUIPC support forum) but the newest version -and questions- can only be done once logged in at SimFlight Forums, and I think that only works via FSUIPC and therefore not in remote mode. Unfortunately I had a severe PC crash and lost my SimFlight password and since last week I have been trying to recover it and even with a new account but they never send me the reset or confirmation emails. Tried contacting them via Contact Us and no response either.


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The P3D SDKs are free downloads. No purchase necessary, just register with L-M on the P3D site first.


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Ok, LOW. From the P3D SDK page:

The Prepar3D® v3 SDK is available as a free download to anyone looking to get into developing add-ons or content for Prepar3D® v3.

The Prepar3D v3 SDK is the current version and should be used to develop new content for Prepar3D v3. The SimConnect.lib and LockheedMartin.Prepar3D.SimConnect.dll provided in the SDK can not be used to connect to FSX, ESP or any previous release of Prepar3D.

The SimConnect server in the Prepar3D v3 application is backwards compatible with the SimConnect.dll’s of P3D 2.x, P3D 1.x, FSX and ESP and the ESP SimConnect server is backwards compatible with the SimConnect.dll’s of FSX. This means that if you are trying to develop an add on that will work with FSX, ESP, Prepar3D v2, and Prepar3D, you will need to use a version of the SimConnect SDK that works with FSX.
So you can use the FSX simconnect and the FSX SDK to create P3D addons. I don't have P3D, but I suspect they are not misleading us.


I just downloaded the P3d v3 SDK, and it has a variety of 'managed' simconnect examples. 'managed' = C#
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Hi Tom (@hairyspin) thanks for the info, somewhere in the LM site I read that the SDK was only available if you had a Developer's license but I followed your tip and indeed found the SDKs readily available on their site. Still no luck on getting access to SimFlight forums, I think they are no longer managing that.

Dick (@rhumbaflappy) yup, I am a bit familiar with those managed examples, although I had until now preferred working with the FSUIPClient.NET but that doesn't fit my bill in this project. Just read that statement too so I will have to install the P3D v2.5 SDK side by side with the FSX SDK.