UseMiddlewareExtensions_Extract2.cs

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

/// <summary>
/// Adds a middleware type to the application's request pipeline.
/// </summary>
/// <param name="app">The <see cref="IApplicationBuilder"/> instance.</param>
/// <param name="middleware">The middleware type.</param>
/// <param name="args">The arguments to pass to the middleware type instance's constructor.</param>
/// <returns>The <see cref="IApplicationBuilder"/> instance.</returns>
public static IApplicationBuilder UseMiddleware(this IApplicationBuilder app, [DynamicallyAccessedMembers(MiddlewareAccessibility)] Type middleware, params object?[] args)
{
	if (typeof(IMiddleware).IsAssignableFrom(middleware))
	{
		// IMiddleware doesn't support passing args directly since it's
		// activated from the container
		if (args.Length > 0)
		{
			throw new NotSupportedException(Resources.FormatException_UseMiddlewareExplicitArgumentsNotSupported(typeof(IMiddleware)));
		}

		return UseMiddlewareInterface(app, middleware);
	}

	var applicationServices = app.ApplicationServices;
	return app.Use(next =>
	{
        // contents elided for this example
	});
}