razor

https://cloud.tencent.com/developer/ask/59115

https://blog.csdn.net/megoodtoo/article/details/77160561

IRazorLightEngine engine = EngineFactory.CreatePhysical("Path-to-your-views");

// Files and strong models
string resultFromFile = engine.Parse("Test.cshtml", new Model("SomeData"));

https://weblog.west-wind.com/posts/2010/dec/27/hosting-the-razor-engine-for-templating-in-nonweb-applications

https://andrewlock.net/configuring-environment-specific-services-in-asp-net-core/

https://inneka.com/programming/c/return-view-as-string-in-net-core/

https://medium.com/a-layman/refactor-your-html-report-with-razorengine-59e878ac9d52

https://stackoverflow.com/questions/40912375/return-view-as-string-in-net-core

https://ppolyzos.com/2016/09/09/asp-net-core-render-view-to-string/

https://long2know.com/2017/08/rendering-and-emailing-embedded-razor-views-with-net-core/

https://medium.com/a-layman/refactor-your-html-report-with-razorengine-59e878ac9d52

using System.Diagnostics;
	using System.IO;
	using System.Reflection;
	using System.Threading.Tasks;
	using ClassLibrary;
	using Microsoft.AspNetCore.Hosting;
	using Microsoft.AspNetCore.Hosting.Internal;
	using Microsoft.AspNetCore.Mvc.Razor;
	using Microsoft.Extensions.DependencyInjection;
	using Microsoft.Extensions.FileProviders;
	using Microsoft.Extensions.ObjectPool;
	using Microsoft.Extensions.PlatformAbstractions;

	namespace Console
	{
	class Program
	{
	static async Task Main(string[] args)
	{
	var renderer = GetRenderer();
	var html = await renderer.RenderViewToStringAsync("/Myview.cshtml", new MyModel());
	System.Console.Write(html);
	System.Console.ReadKey();
	}

	private static RazorViewToStringRenderer GetRenderer()
	{
	var services = new ServiceCollection();
	var applicationEnvironment = PlatformServices.Default.Application;
	services.AddSingleton(applicationEnvironment);

	var appDirectory = Directory.GetCurrentDirectory();

	var environment = new HostingEnvironment
	{
	ApplicationName = Assembly.GetEntryAssembly().GetName().Name
	};
	services.AddSingleton<IHostingEnvironment>(environment);

	services.Configure<RazorViewEngineOptions>(options =>
	{
	options.FileProviders.Clear();
	options.FileProviders.Add(new PhysicalFileProvider(appDirectory));
	});

	services.AddSingleton<ObjectPoolProvider, DefaultObjectPoolProvider>();

	var diagnosticSource = new DiagnosticListener("Microsoft.AspNetCore");
	services.AddSingleton<DiagnosticSource>(diagnosticSource);

	services.AddLogging();
	services.AddMvc();
	services.AddSingleton<RazorViewToStringRenderer>();
	var provider = services.BuildServiceProvider();
	return provider.GetRequiredService<RazorViewToStringRenderer>();
	}
	}
	}

// 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.

	using System;
	using System.IO;
	using System.Linq;
	using System.Threading.Tasks;
	using Microsoft.AspNetCore.Http;
	using Microsoft.AspNetCore.Mvc;
	using Microsoft.AspNetCore.Mvc.Abstractions;
	using Microsoft.AspNetCore.Mvc.ModelBinding;
	using Microsoft.AspNetCore.Mvc.Razor;
	using Microsoft.AspNetCore.Mvc.Rendering;
	using Microsoft.AspNetCore.Mvc.ViewEngines;
	using Microsoft.AspNetCore.Mvc.ViewFeatures;
	using Microsoft.AspNetCore.Routing;

	namespace Mvc.RenderViewToString
	{
	public class RazorViewToStringRenderer
	{
	private IRazorViewEngine _viewEngine;
	private ITempDataProvider _tempDataProvider;
	private IServiceProvider _serviceProvider;

	public RazorViewToStringRenderer(
	IRazorViewEngine viewEngine,
	ITempDataProvider tempDataProvider,
	IServiceProvider serviceProvider)
	{
	_viewEngine = viewEngine;
	_tempDataProvider = tempDataProvider;
	_serviceProvider = serviceProvider;
	}

	public async Task<string> RenderViewToStringAsync<TModel>(string viewName, TModel model)
	{
	var actionContext = GetActionContext();
	var view = FindView(actionContext, viewName);

	using (var output = new StringWriter())
	{
	var viewContext = new ViewContext(
	actionContext,
	view,
	new ViewDataDictionary<TModel>(
	metadataProvider: new EmptyModelMetadataProvider(),
	modelState: new ModelStateDictionary())
	{
	Model = model
	},
	new TempDataDictionary(
	actionContext.HttpContext,
	_tempDataProvider),
	output,
	new HtmlHelperOptions());

	await view.RenderAsync(viewContext);

	return output.ToString();
	}
	}

	private IView FindView(ActionContext actionContext, string viewName)
	{
	var getViewResult = _viewEngine.GetView(executingFilePath: null, viewPath: viewName, isMainPage: true);
	if (getViewResult.Success)
	{
	return getViewResult.View;
	}

	var findViewResult = _viewEngine.FindView(actionContext, viewName, isMainPage: true);
	if (findViewResult.Success)
	{
	return findViewResult.View;
	}

	var searchedLocations = getViewResult.SearchedLocations.Concat(findViewResult.SearchedLocations);
	var errorMessage = string.Join(
	Environment.NewLine,
	new[] { $"Unable to find view '{viewName}'. The following locations were searched:" }.Concat(searchedLocations)); ;

	throw new InvalidOperationException(errorMessage);
	}

	private ActionContext GetActionContext()
	{
	var httpContext = new DefaultHttpContext();
	httpContext.RequestServices = _serviceProvider;
	return new ActionContext(httpContext, new RouteData(), new ActionDescriptor());
	}
	}
	}