.net – How to add folder to assembly search path at runtime in .NET

assembliesnetpathsearch

My DLLs are loaded by a third-party application, which we can not customize. My assemblies have to be located in their own folder. I can not put them into GAC (my application has a requirement to be deployed using XCOPY).
When the root DLL tries to load resource or type from another DLL (in the same folder), the loading fails (FileNotFound).
Is it possible to add the folder where my DLLs are located to the assembly search path programmatically (from the root DLL)? I am not allowed to change the configuration files of the application.

Best Answer

Sounds like you could use the AppDomain.AssemblyResolve event and manually load the dependencies from your DLL directory.

Edit (from the comment):

AppDomain currentDomain = AppDomain.CurrentDomain;
currentDomain.AssemblyResolve += new ResolveEventHandler(LoadFromSameFolder);

static Assembly LoadFromSameFolder(object sender, ResolveEventArgs args)
{
    string folderPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
    string assemblyPath = Path.Combine(folderPath, new AssemblyName(args.Name).Name + ".dll");
    if (!File.Exists(assemblyPath)) return null;
    Assembly assembly = Assembly.LoadFrom(assemblyPath);
    return assembly;
}

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C# – How to get the path of the assembly the code is in

I've defined the following property as we use this often in unit testing.

public static string AssemblyDirectory
{
    get
    {
        string codeBase = Assembly.GetExecutingAssembly().CodeBase;
        UriBuilder uri = new UriBuilder(codeBase);
        string path = Uri.UnescapeDataString(uri.Path);
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    }
}

The Assembly.Location property sometimes gives you some funny results when using NUnit (where assemblies run from a temporary folder), so I prefer to use CodeBase which gives you the path in URI format, then UriBuild.UnescapeDataString removes the File:// at the beginning, and GetDirectoryName changes it to the normal windows format.

C# – How to enable assembly bind failure logging (Fusion) in .NET

Add the following values to

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Fusion
Add:
DWORD ForceLog set value to 1
DWORD LogFailures set value to 1
DWORD LogResourceBinds set value to 1
DWORD EnableLog set value to 1
String LogPath set value to folder for logs (e.g. C:\FusionLog\)

Make sure you include the backslash after the folder name and that the Folder exists.

You need to restart the program that you're running to force it to read those registry settings.

By the way, don't forget to turn off fusion logging when not needed.

Best Answer

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C# – How to get the path of the assembly the code is in

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