.Net Assembly Binding Redirect with Differing Public Key Tokens
Is it possible to perform an assembly binding redirect between different versions of a referenced assembly if the public key token is null on the older version and set on the newer version?
For example, I have two assemblies...
System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null
and
System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
Should the following assembly binding redirect work in the Asp.Net web.config...
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0" newVersion="2.0.0.0"/>
</dependentAssembly>
</assemblyBinding>
</runtime>
No, it is not possible. The assemblies need to have the same publicKeyToken.
The bindingRedirect tag only has the oldVersion and newVersion attributes, so there's no way to tell it about the "null" version anyway.
But the real reason behind is explained due to the strong name mechanism
You might be able to use the AppDomain.AssemblyResolve event to do that. I've included some sample code in this answer.