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c#-3.0clr

How to reference a specific DLL for functionality in said DLL

Good day,

I have an application that I developed that transfers files between two machines ("site" and "server"). This application was set to target dotNet 3.5. Furthermore, I am using Renci.SshNet to handle the connections between the machines and the transferring of said files.

The issue that I am facing currently though is that about 70% of the "site" machines do not have a standard dotNet and is also quite old; thus these machines do not support all the required functionality as the external dll makes calls to System.Threading.WaitHandle.WaitOne() and System.Threading.WaitHandle.WaitAny(WaitHandle[], Int32) and other overloads of these methods.

The workaround that I have for this though is to install netfx20SP2 or netfx30SP1, yet I am not in the position to perform this update on all machines as they are scattered across the country and have data limitations (bandwidth and cap).

What I want to do possibly is to embed the System.Threading dll that I have downloaded and then the application should use those classes instead, or alternatively just point the application to use the said dll.

Is this at all possible, or do you have to load the dll into the GAC? And also, will it be possible to "run" this higher version of System.Threading in the application while the system itself is on a lower framework version. Something is telling me that the best bet will be to actually run the service pack installation to avoid unnecessary coding but I'm not sure exactly how to approach this.

Thank you in advance for any assistance / suggestions, JD

Solution

  • To allow the execution of an application that, let's say, targets .Net 4; while the machine itself only has let's say, .Net 3.5, installed, one can redirect Windows to check the local (executing) directory for dlls that should contain the required symbols loaded into memory instead of the default symbols that get loaded upon execution (the default would be the NetFx installed on the machine - which I believe the highest version of the framework that can be found upon loading when the execution starts or would be the highest available version that is lower or equal to the targeted framework).

    This file's contents (myApp.exe.local) are ignored. It is just there to tell Windows to look in that folder for the applicable symbols and if not found, the system will roll back to attempt to load these symbols from the NetFx directory.

    Read more at Microsoft Dev Center - Docs (link is attached to the following paragraph which is a Copy-Paste of a section of this document).

    To use DLL redirection, create a redirection file for your application. The redirection file must be named as follows: App_name.local. For example, if the application name is Editor.exe, the redirection file should be named Editor.exe.local. You must install the .local file in the application directory. You must also install the DLLs in the application directory.