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I found some article how to return view to string in ASP.NET, but could not covert any to be able to run it with .NET Core

public static string RenderViewToString(this Controller controller, string viewName, object model)

{

    var context = controller.ControllerContext;

    if (string.IsNullOrEmpty(viewName))

        viewName = context.RouteData.GetRequiredString("action");



    var viewData = new ViewDataDictionary(model);



    using (var sw = new StringWriter())

    {

        var viewResult = ViewEngines.Engines.FindPartialView(context, viewName);

        var viewContext = new ViewContext(context, viewResult.View, viewData, new TempDataDictionary(), sw);

        viewResult.View.Render(viewContext, sw);



        return sw.GetStringBuilder().ToString();

    }

}

which assumed to be able to call from a Controller using:

var strView = this.RenderViewToString("YourViewName", yourModel);

When I try to run the above into .NET Core I get lots of compilation errors.

I tried to convert it to work with .NET Core, but failed, can anyone help with mentioning the required using .. and the required "dependencies": {
"Microsoft.AspNetCore.Mvc": "1.1.0",
...
}, to be used in the project.json.

some other sample codes are here and here and here

NOTE
I need the solution to get the view converted to string in .NET Core, regardless same code got converted, or another way that can do it.

Thanks to Paris Polyzos and his article.

I'm re-posting his code here, just in case the original post got removed for any reason.

Create Service in file viewToString.cs as below code:

using System;

using System.IO;

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.ViewFeatures;

using Microsoft.AspNetCore.Routing;

 

namespace WebApplication.Services

{

    public interface IViewRenderService

    {

        Task<string> RenderToStringAsync(string viewName, object model);

    }

 

    public class ViewRenderService : IViewRenderService

    {

        private readonly IRazorViewEngine _razorViewEngine;

        private readonly ITempDataProvider _tempDataProvider;

        private readonly IServiceProvider _serviceProvider;

 

        public ViewRenderService(IRazorViewEngine razorViewEngine,

            ITempDataProvider tempDataProvider,

            IServiceProvider serviceProvider)

        {

            _razorViewEngine = razorViewEngine;

            _tempDataProvider = tempDataProvider;

            _serviceProvider = serviceProvider;

        }

 

        public async Task<string> RenderToStringAsync(string viewName, object model)

        {

            var httpContext = new DefaultHttpContext { RequestServices = _serviceProvider };

            var actionContext = new ActionContext(httpContext, new RouteData(), new ActionDescriptor());

 

            using (var sw = new StringWriter())

            {

                var viewResult = _razorViewEngine.FindView(actionContext, viewName, false);

 

                if (viewResult.View == null)

                {

                    throw new ArgumentNullException($"{viewName} does not match any available view");

                }

 

                var viewDictionary = new ViewDataDictionary(new EmptyModelMetadataProvider(), new ModelStateDictionary())

                {

                    Model = model

                };

 

                var viewContext = new ViewContext(

                    actionContext,

                    viewResult.View,

                    viewDictionary,

                    new TempDataDictionary(actionContext.HttpContext, _tempDataProvider),

                    sw,

                    new HtmlHelperOptions()

                );

 

                await viewResult.View.RenderAsync(viewContext);

                return sw.ToString();

            }

        }

    }

}

2. 
   

   Add the service to the Startup.cs file, as:

   
   
   

   using WebApplication.Services;
   
   
   
   public void ConfigureServices(IServiceCollection services)
   
   {
   
       ...
   
       services.AddScoped<IViewRenderService, ViewRenderService>();
   
    }
   
   

   
   

Add "preserveCompilationContext": true to the buildOptions in the project.json, so the file looks like:

{

  "version": "1.0.0-*",

  "buildOptions": {

    "debugType": "portable",

    "emitEntryPoint": true,

    "preserveCompilationContext": true

  },

  "dependencies": {

    "Microsoft.AspNetCore.Server.Kestrel": "1.0.1",

    "Microsoft.AspNetCore.Mvc": "1.0.1"

  },

  "frameworks": {

    "netcoreapp1.0": {

      "dependencies": {

        "Microsoft.NETCore.App": {

          "type": "platform",

          "version": "1.0.1"

        }

      },

      "imports": "dnxcore50"

    }

  }

}

4. 
   

   Define you model, for example:

   
   
   

   public class InviteViewModel {
   
       public string   UserId {get; set;}
   
       public string   UserName {get; set;}
   
       public string   ReferralCode {get; set;}
   
       public int  Credits {get; set;}
   
   }
   
   

   
   


5. 
   

   Create your Invite.cshtml for example:

   
   
   

   @{
   
       ViewData["Title"] = "Contact";
   
   }
   
   @ViewData["Title"].
   
   user id: @Model.UserId
   
   

   
   



6. In the Controller:

a. Define the below at the beginning:

private readonly IViewRenderService _viewRenderService;

 

public RenderController(IViewRenderService viewRenderService)

{

    _viewRenderService = viewRenderService;

}

b. Call and return the view with model as below:

var result = await _viewRenderService.RenderToStringAsync("Email/Invite", viewModel);

return Content(result);

c. The FULL controller example, could be like:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Threading.Tasks;

using Microsoft.AspNetCore.Mvc;



using WebApplication.Services;



namespace WebApplication.Controllers

{

[Route("render")]

public class RenderController : Controller

{

    private readonly IViewRenderService _viewRenderService;

 

    public RenderController(IViewRenderService viewRenderService)

    {

        _viewRenderService = viewRenderService;

    }

 

    [Route("invite")]

    public async Task<IActionResult> RenderInviteView()

    {

        ViewData["Message"] = "Your application description page.";

        var viewModel = new InviteViewModel

        {

            UserId = "cdb86aea-e3d6-4fdd-9b7f-55e12b710f78",

            UserName = "Hasan",

            ReferralCode = "55e12b710f78",

            Credits = 10

        };

 

        var result = await _viewRenderService.RenderToStringAsync("Email/Invite", viewModel);

        return Content(result);

    }

}



public class InviteViewModel {

        public string   UserId {get; set;}

        public string   UserName {get; set;}

        public string   ReferralCode {get; set;}

        public int  Credits {get; set;}

} 

}

If like me you have a number of controllers that need this, like in a reporting site, it's not really ideal to repeat this code, and even injecting or calling another service doesn't really seem right.

So I've made my own version of the above with the following differences:

• model strong-typing


• error checking when finding a view


• ability to render views as partials or pages


• asynchronus


• implemented as a controller extension


• 
  

  no DI needed

  
  
  

  using Microsoft.AspNetCore.Mvc;
  
  using Microsoft.AspNetCore.Mvc.Rendering;
  
  using Microsoft.AspNetCore.Mvc.ViewEngines;
  
  using Microsoft.AspNetCore.Mvc.ViewFeatures;
  
  using System.IO;
  
  using System.Threading.Tasks;
  
  
  
  namespace CC.Web.Helpers
  
  {
  
      public static class ControllerExtensions
  
      {
  
          public static async Task<string> RenderViewAsync<TModel>(this Controller controller, string viewName, TModel model, bool partial = false)
  
          {
  
              if (string.IsNullOrEmpty(viewName))
  
              {
  
                  viewName = controller.ControllerContext.ActionDescriptor.ActionName;
  
              }
  
  
  
              controller.ViewData.Model = model;
  
  
  
              using (var writer = new StringWriter())
  
              {
  
                  IViewEngine viewEngine = controller.HttpContext.RequestServices.GetService(typeof(ICompositeViewEngine)) as ICompositeViewEngine;
  
                  ViewEngineResult viewResult = viewEngine.FindView(controller.ControllerContext, viewName, !partial);
  
  
  
                  if (viewResult.Success == false)
  
                  {
  
                      return $"A view with the name {viewName} could not be found";
  
                  }
  
  
  
                  ViewContext viewContext = new ViewContext(
  
                      controller.ControllerContext,
  
                      viewResult.View,
  
                      controller.ViewData,
  
                      controller.TempData,
  
                      writer,
  
                      new HtmlHelperOptions()
  
                  );
  
  
  
                  await viewResult.View.RenderAsync(viewContext);
  
  
  
                  return writer.GetStringBuilder().ToString();
  
              }
  
          }
  
      }
  
  }
  
  

  
  

Then just implement with:

viewHtml = await this.RenderViewAsync("Report", model);

Or this for a PartialView:

partialViewHtml = await this.RenderViewAsync("Report", model, true);

The link below tackles pretty much the same issue:

Where are the ControllerContext and ViewEngines properties in MVC 6 Controller?

In Hasan A Yousef's answer I had to make the same change as in the link above to make it work me:

using Microsoft.AspNetCore.Hosting;

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.ViewFeatures;

using Microsoft.AspNetCore.Routing;

using System;

using System.IO;

using System.Threading.Tasks;



public class ViewRenderService : IViewRenderService

{

    private readonly IRazorViewEngine _razorViewEngine;

    private readonly ITempDataProvider _tempDataProvider;

    private readonly IServiceProvider _serviceProvider;

    private readonly IHostingEnvironment _env;



    public ViewRenderService(IRazorViewEngine razorViewEngine, ITempDataProvider tempDataProvider, IServiceProvider serviceProvider, IHostingEnvironment env)

    {

        _razorViewEngine = razorViewEngine; _tempDataProvider = tempDataProvider; _serviceProvider = serviceProvider; _env = env;

    }



    public async Task<string> RenderToStringAsync(string viewName, object model)

    {

        var httpContext = new DefaultHttpContext { RequestServices = _serviceProvider };

        var actionContext = new ActionContext(httpContext, new RouteData(), new ActionDescriptor());



        using (var sw = new StringWriter()) {

            //var viewResult = _razorViewEngine.FindView(actionContext, viewName, false);

            var viewResult = _razorViewEngine.GetView(_env.WebRootPath, viewName, false);

            if (viewResult.View == null) {

                throw new ArgumentNullException($"{viewName} does not match any available view");

            }

            var viewDictionary = new ViewDataDictionary(new EmptyModelMetadataProvider(), new ModelStateDictionary()) {

                Model = model

            };

            var viewContext = new ViewContext(actionContext, viewResult.View, viewDictionary, new TempDataDictionary(actionContext.HttpContext, _tempDataProvider), sw, new HtmlHelperOptions());

            await viewResult.View.RenderAsync(viewContext);

            return sw.ToString();

        }

    }