private static Assembly?LoadFromResolveHandler(object?sender, ResolveEventArgs args)
{
Assembly?requestingAssembly = args.RequestingAssembly;
if (requestingAssembly == null)
{
return(null);
}
// Requesting assembly for LoadFrom is always loaded in defaultContext - proceed only if that
// is the case.
if (AssemblyLoadContext.Default != AssemblyLoadContext.GetLoadContext(requestingAssembly))
{
return(null);
}
// Get the path where requesting assembly lives and check if it is in the list
// of assemblies for which LoadFrom was invoked.
string requestorPath = Path.GetFullPath(requestingAssembly.Location);
if (string.IsNullOrEmpty(requestorPath))
{
return(null);
}
lock (s_loadFromAssemblyList)
{
// If the requestor assembly was not loaded using LoadFrom, exit.
if (!s_loadFromAssemblyList.Contains(requestorPath))
{
#if CORECLR
if (AssemblyLoadContext.IsTracingEnabled())
{
AssemblyLoadContext.TraceAssemblyLoadFromResolveHandlerInvoked(args.Name, false, requestorPath, null);
}
#endif // CORECLR
return(null);
}
}
// Requestor assembly was loaded using loadFrom, so look for its dependencies
// in the same folder as it.
// Form the name of the assembly using the path of the assembly that requested its load.
AssemblyName requestedAssemblyName = new AssemblyName(args.Name !);
string requestedAssemblyPath = Path.Combine(Path.GetDirectoryName(requestorPath) !, requestedAssemblyName.Name + ".dll");
#if CORECLR
if (AssemblyLoadContext.IsTracingEnabled())
{
AssemblyLoadContext.TraceAssemblyLoadFromResolveHandlerInvoked(args.Name, true, requestorPath, requestedAssemblyPath);
}
#endif // CORECLR
try
{
// Load the dependency via LoadFrom so that it goes through the same path of being in the LoadFrom list.
return(Assembly.LoadFrom(requestedAssemblyPath));
}
catch (FileNotFoundException)
{
// Catch FileNotFoundException when attempting to resolve assemblies via this handler to account for missing assemblies.
return(null);
}
}
