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Duplex WCF Service runs into NullReferenceException

Posted By:      Posted Date: May 22, 2011    Points: 0   Category :SharePoint
 

This question grew out of http://social.msdn.microsoft.com/Forums/en-US/wcf/thread/3ebbca54-5ebe-4ca3-a014-18036786982f (Duplex WCF Service - How to have it wait before doing the callback) but is logically independent.

A zip file is available at http://rad129.net/SRacq10.zip; it contains one VS2010 solution with two VB.Net projects. In order to show the problem succinctly, they are greatly condensed versions of my actual projects.

Project SRacq10 is a Windows Forms app that provides a duplex WCF service in file SU_ProvidesWCFservice.vb. The constructor of SU_MDI.vb starts the service.

Project TestSRacq10 is also a WinForms app; it contains the client: file SU_ConsumesWCFservice.vb has the definitions. The code in frmTSU sends commands and receives messages, and logs what's happening to RichTextBox rtbLog.

To make endpoint http://localhost:8080/Raad10/SU_WCF accessible, I have to run netsh in a command window similar to:
netsh http add urlacl url=http://+:8080/Raad10 user=mycomputer\myuserid

After opening the solution in VS2010, and possibly rebuilding TestSRacq10, run TestSRacq10.exe, say, from Win Explorer.

Now run SR


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