How to handle dynamically loaded managed libraries in C #

Question

I wrote an application in C # and added some kind of API for it. With this API, you can write plugins as dlls that underlie some interface rules.

I want to open a dll file through OpenFileDialog and use its contents. My API is a managed library, so I just add the link, but I want to use dll without knowing the dll file name. In addition, the namespace is another library.

How to load a DLL and run the code inside it?

Answer 1

What you describe is usually called a plugin system. Googling for something like "Create Plugin system using C #" will probably give you a lot of information, like below:

http://www.codeproject.com/Articles/4691/Plugin-Architecture-using-C

Main idea:

• Define the interface that your program implements so that the plugin can receive information from your program.
• Define the interface that all plugins will implement so that your program calls plugin methods that will do something.
• Put these interfaces in a separate dll, which is referenced by your program and any plug-ins.
• Provide some way to search for dlls with types that implement your plugin interface, for example. your OpenFileDialog.
• Download the dll and find the types that implement your plugin interface (using reflection).
• Import these types using reflection.
• Call methods on these types through the interface, if necessary.

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Relatively managed / non-managed. A managed DLL is one that is built / encoded using a managed .net environment. These will be things encoded in the .net language, for example C # .

An unmanaged dll is more or less encoded in another language.

What you would call an unmanaged dll, I would call a dynamically loaded managed dll. That is, it is still a managed dll (encoded in .net language), but is not loaded until the program is launched.

Answer 2

You can load a managed assembly from a DLL file using the Assembly.LoadFrom Method (String) (See also Assembly Recommendations ).