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javascriptc#asp.net-core-mvc

JavaScriptEngineSwitcher loading resource javascript file failing

I have a .NET 8 Core C# MVC project to provide the content as website and a class library to host the logic.

I'm trying to run ua-parser-js through JavaScriptEngineSwitcher as I couldnt find a C# based project like this which was recently updated.

I installed the nuget packages to my class library and added the JsEngineSwitcher to the available services in my MVC projects Program.cs file.

builder.Services.AddJsEngineSwitcher(options =>
{
    options.AllowCurrentProperty = false;
    options.DefaultEngineName = JintJsEngine.EngineName;
}).AddJint();

In my Controller I load the injected Service as below

var jsEngineSwitcher = _serviceProvider.GetService<IJsEngineSwitcher>();
var engine = jsEngineSwitcher.CreateDefaultEngine();

I'm passing the UA and the engine to my class library method where I am trying to load the JS file. The JS file is added as a embedded ressource in the root folder of the class library.

engine.ExecuteResource("<class library name>.ua-parser.min.js", typeof(Program).Assembly);

Unfortunately this fails with

System.NullReferenceException: 'Resource with name '<class library name>.ua-parser.min.js' is null.'

I checked if the JS file is really exiting as a ressource by below code, and it does have ".ua-parser.min.js"

System.Reflection.Assembly.GetExecutingAssembly().GetManifestResourceNames();

The sample projects in the github repo seem not to load any JS and I wasn't able to find a recent example except this.

Anyone having an idea what I am doing wrong?

Solution

  • Figured it out, instead of

    engine.ExecuteResource("<class library name>.ua-parser.min.js", typeof(Program).Assembly);

    I had to use

    engine.ExecuteResource("<class library name>.ua-parser.min.js", typeof(<class library name here>).Assembly);