What is the best way to Inject IOptions<T> in _Layout

Question

I built a small web app using ASP.NET Core Razor Pages, but I want to using IOptions<T> to pass settings from app.json in _Layout. Thanks!

Answer 1

You can use the @inject Razor directive to inject services into your Razor views. Of course, that also includes options. So if you have some MyOptions class that you have configured (e.g. using services.Configure<MyOptions>(options => { … }) in the Startup class), then you can just inject the options into the .cshtml:

@inject IOptions<MyOptions> myOptions

<h1>@myOptions.Value.ApplicationTitle</h1>
<p>@myOptions.Value.ApplicationIntroText</p>

To avoid having to access myOptions.Value explicitly all the time, you can also use a code block and store the result in a local variable first:

@inject IOptions<MyOptions> myOptions
@{
    var opts = myOptions.Value;
}

<h1>@opts.ApplicationTitle</h1>
<p>@opts.ApplicationIntroText</p>