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C#: use "Class Library" Project for plugins

this question follows my previous question.
I have a c# ASP.NET application and i want to provide support for plugins. Plugins can be custom c# classes, javascript, html, css, images, etc.
I see no problem as long as my application is extended with c# classes because all the user has to do is create a new "class library" project in visual studio and implement the interfaces, i provide. Then build a dll out of it and upload it to my server. The plugin-developer can add static files (html, js, css, etc.) into this project as well but i found some problems with that:
Every static file i add to the plugin project gets the build action "content" and it seems i cannot read those files from my server. (see my previously answered question). I have to manually select "Embedded Resource" on each file, so it is packed with the plugin dll.
I want to support Typescript for the plugins. The Typescript compiler generates javascript files in the same directory as the typescript-files. But the javascript files are not included in the project and therefore i have to include these in the plugin project and then set the correct build action. I don't want the plugin developers to do that all the time.
If the static files have the build action "enbedded resources", then the server can pickup these files by using the assembly.GetManifestResourceNames() method. This method returns the resources as a string. The path is not separated by \ or / but with a dot instead. So i am not able to distinguish between file path (this is relevant) or filename (also relevant to pickup the correct files), because the original filename can also have dots.
So i am starting to question the "class library" project type is right for my needs. Is there a way to get around of my issues or do i have to use another project type?
Thank you for any help!
Edit: Changed the question a little bit so it is better to understand.

You could make a zip package with the plugin dll and files. NuGet also uses this mechanism. A .nupkg is also just a zip file.

I would start by looking at MEF (Managed Extensibility Framework).
MSDN information can be found here: https://msdn.microsoft.com/en-us/library/dd460648(v=vs.110).aspx
From that link you can get more information and I believe there is a tutorial as well.

Oh, for me it seems very simple.
Let the developer create the plugin freestyle and put all the additional files in a directory, let's call it extras
To implement the your interface they will need your assembly so I guess you will ship it via nuget, or just some link. No matter what the case, provide them with some powershell script what will be required to run before the final build
The script would create zip archive from the extras directory and add it to the ClassLibrary project as EmbeddedResource.
As you mentioned earlier, you can access EmbeddedResource. So all you would do is to unpack it and you would have the exact directory tree.
The best idea would be to provide project template with script included, and also the empty zip archive added as embedded resource (it will be easier to just pack the files in the script and replace the file), and pre-build action set to run the script.
Am I missing something?

What about this.
In your web application, you could add a function that loop into your plugin directory and find DLL implementing an Iplugin (name is up to you) interface.
The interface is defined in a class library that both your web application and plugins have to implement.
You can use the Httpcontext Server mappath to read javascript and other files.
Here is a very basic implementation
First, you have the plugin interface (a class library implemented both by the web application and the individual plugins) I implemented sample properties and methods...
using System.Web;
public interface IPlugin
{
string Name { get; set; }
string Output { get; set; }
void Load(ref httpcontext Context);
void Dispose();
void Display();
}
Next, you have the Actual plugin class library we want to implement.
using System.Web;
using IPlugins;
public class AwesomePlugin : IPlugins.IPlugin
{
private string _Name = "AwesomePlugin";
private HttpContext _Context;
public string Name {
get { return _Name; }
set { _Name = value; }
}
public string Output {
get { return "Yay !!!"; }
set {
throw new NotImplementedException();
}
}
public void Display()
{
throw new NotImplementedException();
}
public void Dispose()
{
throw new NotImplementedException();
}
public void Load(ref Web.HttpContext Context)
{
}
}
Finally, you dynamically load your plugins so you can use them in your application.
private Dictionary<string, IPlugins.IPlugin> _Plugins = new Dictionary<string, IPlugins.IPlugin>();
public void LoadPlugins()
{
lock (static_LoadPlugins_IpluginType_Init) {
try {
if (InitStaticVariableHelper(static_LoadPlugins_IpluginType_Init)) {
static_LoadPlugins_IpluginType = typeof(IPlugins.IPlugin);
}
} finally {
static_LoadPlugins_IpluginType_Init.State = 1;
}
}
string ServerPath = HttpContext.Current.Server.MapPath("~") + "Plugins";
dynamic Plugins = io.Directory.GetFiles(ServerPath);
foreach (string PluginPath in Plugins) {
dynamic Assembly = system.Reflection.Assembly.LoadFile(PluginPath);
Type PluginClass = Assembly.GetTypes.Where(T => T.GetInterface("IPlugin") != null).First;
IPlugins.IPlugin MyPlugin = Activator.CreateInstance(PluginClass);
MyPlugin.Load(httpcontext.Current);
_Plugins.#add(PluginClass.ToString, MyPlugin);
}
}
static bool InitStaticVariableHelper(Microsoft.VisualBasic.CompilerServices.StaticLocalInitFlag flag)
{
if (flag.State == 0) {
flag.State = 2;
return true;
} else if (flag.State == 2) {
throw new Microsoft.VisualBasic.CompilerServices.IncompleteInitialization();
} else {
return false;
}
}
That way, you can implement whatever you want in your plugin.
I believe you could load your plugins in a separate appdomain with restricted permissions to everything.
The files (Javascript / CSS / Html) should be available by accessing the full path of the file.
string ServerPath = HttpContext.Current.Server.MapPath("~") + "Plugins";
If the resources is embedded into the plugin DLL, you could read the stream from the loaded assembly or let the plugin manage its own embedded files.

For question Number 2, you can use
MS Build
to change the contenttype during build process.
You have to make yourself confident with MS Build

Different resource files for different client deployments

I'm developing a WinForms application for 2 clients. The difference between the clients are only in branding: ClientA gets LogoA.png. ClientB gets LogoB.png. I need to ship the application to them as in installer and as zip file with all executables.
I'm thinking putting the images in different resource files and compile them as satellite assemblies and on the build server, when I produce zip-file and installer, I include only ResourceA for ClientA and ResourceB for ClientB. That is the plan, but I've never done this before.
The documentation says that resource files should be identified by language and culture codes. Both of my clients will run their machines in English (en-GB or en-US). I can ignore the recommendation and call the resources by the name of clients. But would they be picked up by the application? (taking there is only one resource file and machine culture does not match the resource culture code).
Is there a better solution for that?
p.s. I know about compiler directives, but it is making code hacky and dirty. Possibly, in the future, clients will have different text on the screens and that is the perfect case for the resources.

You can create a separate build configuration for each company. Then you can change the .csproj file to have msbuild tasks which will replace default resource file with chosen company resources, here is example how to check current configuration in msbuild.
<PropertyGroup Condition="'$(Configuration)' == 'CompanyABuild'">
//set resource to point to company A
</PropertGroup>
<PropertyGroup Condition="'$(Configuration)' == 'CompanyBBuild'">
//set resource to point to company B
</PropertGroup>

You can add to separate resource file one for clientA another one for clientB (ClientA.resx, Clinetb.resx). Then add a config entry in your app.config file with the name of the resource to use.
Then you need to create a wrapper class which will provide you resources depending on the config value, you need to use dynamic objects and resource managers here is a sample code:
class Program
{
static void Main(string[] args)
{
var res = new CompanyAResource();
var companyResources = new global::System.Resources.ResourceManager("ConsoleApplication1.CompanyAResource", typeof(CompanyAResource).Assembly);
dynamic resources = new DynamicResources(companyResources);
string name = resources.CompanyName;
Console.WriteLine(name);
}
}
public class DynamicResources : System.Dynamic.DynamicObject
{
private ResourceManager resources;
public DynamicResources(ResourceManager resources)
{
this.resources = resources;
}
public override bool TryGetMember(System.Dynamic.GetMemberBinder binder, out object result)
{
result = this.resources.GetString(binder.Name);
return true;
}
}

How to use .resx and .resource files in custom server control asp?

I am writing my own server side control and I am using images that are being stored in a .resx file. In the console application this code works fine:
ResXResourceReader rsxr = new ResXResourceReader("Resource1.resx");
foreach (DictionaryEntry d in rsxr)
{
Console.WriteLine(d.Key.ToString() + ":\t" + d.Value.ToString());
}
rsxr.Close();
but here
protected override void RenderContents(HtmlTextWriter output)
{
ResXResourceReader rsxr = new ResXResourceReader("Resource1.resx");
base.RenderContents(output);
foreach (DictionaryEntry d in rsxr)
{
output.Write(d.Key.ToString());
}
}
I get this error:
Could not find file 'C:\Program Files\Common Files\Microsoft Shared\DevServer\10.0\Resource1.resx'
I tried to use the ResourceManager, but it requires a .resource file. I can't access the resgen tool (command prompt does not understand the resgen command) and install it (during the attempt some errors ocured).
My questions are:
Why can't I read .resx?
How to install the resgen tool properly?
thanks.

It is considered good practice to store your resource file under App_GlobalResources folder in application root or in App_LocalResources with the same name as your user control file. So for example user user control is uc.ascx file in local resource folder should be uc.ascx.resx. That way it is easier to maintain and asp.net will automatically detect it.
Now your answers:
First Question:
Use Server.MapPath("~/") points to physical directly where your web.config is. If you want to use a resource file in Controls folder you have to write Server.MapPath("~/Controls/Resource1.resx") to get the path.
Not sure what you want to do with resgen tool? When you compile your application, resource file will also be compiled. select your resource file and click F4, it will show you build action, choose resource in build action and your resource file will be included in assembly.
You can review this post for more information: How to use image resource in asp.net website?

From your description, I understand you need to locate and access the user control's resource file. I found that it works nicely the following way:
Create a App_GlobalResources on project level (via context menu Add -> Add ASP.NET Folder -> App_GlobalResources)
Create the ressource file with the same name as the control, but inside the App_GlobalResources. For example, if the control is named myControl.ascx, then the ressource file's name for the default language has to be myControl.ascx.resx
Create additional ressource files for each language you require. For instance, if you need German ("de-DE"), then add myControl.ascx.de.resx
Add the class MultiLanguageUserControl as follows:
public class MultiLanguageUserControl : System.Web.UI.UserControl
{
public string getResValue(string id)
{
var ctrlPath = TemplateControl.AppRelativeVirtualPath;
var ctrlFile = System.IO.Path.GetFileName(ctrlPath);
var resObj = GetGlobalResourceObject(ctrlFile, id);
if (resObj!=null)
return resObj.ToString();
else
return string.Format("UNRESOLVED[{0}]", id);
}
}
Open the code behind of myControl and make it inherit from MultiLanguageUserControl instead from System.Web.UI.UserControl:
public partial class myControl : MultiLanguageUserControl { //... }
In the HTML code, use the new function, e.g.: <%=getResValue("resid")%>, where "resid" is the name of the ressource string you want to look up. You can also use the HTML-encoding tag <%: instead of <%=, depending on your requirements. Alternatively, you can use getResValue anywhere in your server-sided C# code in your user control to retrieve the value from the ressource file.
Ensure that you support the language detection in the Page_Load event of the page, which uses the user control. How you can do this is described here (look for the function InitializeCulture).
NOTE: If you want to read the page's local resource strings from inside the user control then take a look here.

C#.Net automatic resource file designer code generation

In C#.Net when we create a resource file .... Visual Studio generates the designer code for the file automatically. By default the ResourceManager class gets instantiated using the default namespace of the project.
Example
[global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
internal static global::System.Resources.ResourceManager ResourceManager {
get {
if (object.ReferenceEquals(resourceMan, null)) {
global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("ISC.Core.UI.DeployResources", typeof(DeployResources).Assembly);
resourceMan = temp;
}
return resourceMan;
}
}
I want this resource file to be under a custom namespace (say Custom.Default.DeployResources) and not in the default namespace of the project (which in this case is "ISC.Core.UI.DeployResources")
Is there a way to achieve this ?

Right click on your resx, and type your namespace in Custom Tool Namespace.
You can also change the access modifier from internal to public(at the top of your resx when opened in designer) and put your resources in an external assembly.

Could you create a separate project with that default namespace, specifically for resources?

Could not find any resources appropriate for the specified culture or the neutral culture

I have created an assembly and later renamed it.
Then I started getting runtime errors when calling:
toolsMenuName = resourceManager.GetString(resourceName);
The resourceName variable is "enTools" at runtime.
Could not find any resources
appropriate for the specified culture
or the neutral culture. Make sure
"Jfc.TFSAddIn.CommandBar.resources"
was correctly embedded or linked into
assembly "Jfc.TFSAddIn" at compile
time, or that all the satellite
assemblies required are loadable and
fully signed.
The code:
string resourceName;
ResourceManager resourceManager = new ResourceManager("Jfc.TFSAddIn.CommandBar", Assembly.GetExecutingAssembly());
CultureInfo cultureInfo = new CultureInfo(_applicationObject.LocaleID);
if(cultureInfo.TwoLetterISOLanguageName == "zh")
{
CultureInfo parentCultureInfo = cultureInfo.Parent;
resourceName = String.Concat(parentCultureInfo.Name, "Tools");
}
else
{
resourceName = String.Concat(cultureInfo.TwoLetterISOLanguageName, "Tools");
}
toolsMenuName = resourceManager.GetString(resourceName); // EXCEPTION IS HERE
I can see the file CommandBar.resx included in the project, I can open it and can see the "enTools" string there. It seems that either resources are not included into assembly or resource are included but .NET cannot resolve the name.

I think simpler solution would be to create separate resources file for each language.
As far as this case is concerned check if the assembly containing resources has the default namespace set to the same text (Project->Properties->Default namespace; in VS)
Check as well if the resx file has a property BuildAction set to "Embedded resource"

Sounds similar to an issue we had. The namespace was incorrect in the resource file's designer. I fixed it by manually re-running the custom-tool on the resx file.
Right click your.resx, and click Run Custom Tool.

I'm sure you've already got the answer, but just in case:
You can view your ManifestResourceName by calling
System.Reflection.Assembly.GetExecutingAssembly().GetManifestResourceNames()
Check that Manifest name and your name in GetString() calling are identical.
Also, be sure you have correct namespace in designer.resx file:
namespace Jfc.TFSAddIn {
...
global::System.Resources.ResourceManager temp =
new global::System.Resources.ResourceManager(
"Jfc.TFSAddIn.CommandBar", typeof(CommandBar).Assembly);
...
}
Open resx file properties: "Build Action" should be "Embedded Resource"

For me, the source of the problem was naming the rex files starting with a number:
20160216_tranlation.resx
I had to add an underscore _ before the resx file name when calling GetGlobalResourceObject:
public static string getResource(string key)
{
return HttpContext.GetGlobalResourceObject("_20160216_tranlation", key).ToString();
}

I corrected the namespace in designer file (Resources.Designer.cs) in ResourceManager static property & it worked for me.
See the code below:
[global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
internal static global::System.Resources.ResourceManager ResourceManager {
get {
if (object.ReferenceEquals(resourceMan, null)) {
global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("XYZAssembly.Properties.Resources", typeof(Resources).Assembly);
resourceMan = temp;
}
return resourceMan;
}
}

I added a temporary class within my Form.cs while (testing || debugging) that caused this exception to be thrown. The Form.resx file (Name || Resource ID) was modified to the temporary class name instead of the Form class name. This caused the issue for me. I (corrected || alleviated) this by creating a separate file for my temporary class in the project.

One Solution is to change the property of resx file from content to Embedded Resource and Build it.Sure this time u vil get

I have encountered this issue in Xamarin.Forms, when I tried to the rename the project, the resources could not be loaded anymore with the same stated error text.
To fix the problem I had to modify the .csproj by a text editor, and change the logical name of the embedded resource.
<EmbeddedResource Include="Localization\TextResources.resx">
<Generator>ResXFileCodeGenerator</Generator>
<LastGenOutput>TextResources.Designer.cs</LastGenOutput>
<LogicalName>YourNewNamespaceName.TextResources.resources</LogicalName>
<SubType>Designer</SubType>
</EmbeddedResource>
Also watch out for the autogenerated class when you rebuild it, the namespace stated in there might change.
Hope it helps someone that went into the same situation.

Got this error when I added a class ABOVE the partial form class in my Windows forms app.
It went away when I moved the class BELOW the partial form class.

This answer solved the problem for me! GetGlobalResourceObject