CODEWITHSUNDEEP
c#pluginsdll.net-assemblydynamic-loading
Kamran
Kamran

Reputation: 387

Dynamic load a .NET assembly with some other dll dependency

I want to create a plugin engine for my app, but I have a problem: How can I load a .Net assembly (Actually my plugin) which has some dependency to other assembly.

For example I want to load A.DLL and A.DLL need to B.dll or C.dll and so on to run. The A.dll has two method such as A() and B(). And A() or B() use some method of B.dll or C.dll.

What should I do to dynamically load A.DLL and call A() or B()?

Upvotes: 3

Views: 2701

Answers (1)

Massimo
Massimo

Reputation: 21

Use AssemblyResolve event in the current AppDomain:

To load DLLs:

string[] dlls = { @"path1\a.dll", @"path2\b.dll" };
foreach (string dll in dlls)
{
    using (FileStream dllFileStream = new FileStream(dll, FileMode.Open, FileAccess.Read))
    {
         BinaryReader asmReader = new BinaryReader(dllFileStream);
         byte[] asmBytes = asmReader.ReadBytes((int)dllFileStream.Length);
         AppDomain.CurrentDomain.Load(asmBytes);
    }
}
// attach an event handler to manage the assembly loading
AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;

The event handler checks for the name of the assembly and returns the right one:

private static Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
{
    AppDomain domain = (AppDomain)sender;
    foreach (Assembly asm in domain.GetAssemblies())
    {
        if (asm.FullName == args.Name)
        {
            return asm;
        }
    }
    throw new ApplicationException($"Can't find assembly {args.Name}");
}

Upvotes: 2

Related Questions