Nsryjdtyk

I am a bit new to .NET core, i currently have a service which generates email messages and return as a string, however i have a view component in which i usually call in my views and append the result with an already present string:

string result = @await Component.InvokeAsync("Widget", new { widgetZone = "stock_levels_summary_cart_price", additionalData = product.Id })

sb.AppendLine($"<td style="padding: 0.6em 0.4em;text-align: center;">{result}</td>");

how can i call this view component in my service and pass the result into a string in which i can use in my email message service

i was able to implement this by creating a partial view for the view component:

in the partial view, i declared my view component:

@model int



@await Component.InvokeAsync("Widget", new { widgetZone = "stock_levels_summary_cart_price", additionalData = Model})

in my controller created an action as follows:

public virtual PartialViewResult OrderDetailsStocklevel(int productId)

    {



        return PartialView("~/Views/Shared/_OrderDetailsStocklevel.cshtml", productId);

    }

then implemented a service to render the partial view content and return the result:

            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 Nop.Services.Helpers

                {



                    public interface IViewRenderHelper

                    {

                        string RenderToString(string viewName, object model, string viewPath);

                    }



                public class ViewRenderHelper : IViewRenderHelper

                {

                    private readonly IServiceProvider _serviceProvider;



                    public ViewRenderHelper(IServiceProvider serviceProvider)

                    {

                        _serviceProvider = serviceProvider;

                    }



                    public string RenderToString(string viewName, object model, string viewPath)

                    {

                        var httpContext = new DefaultHttpContext { RequestServices = _serviceProvider };

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



                        var engine = _serviceProvider.GetService(typeof(IRazorViewEngine)) as IRazorViewEngine;

                        var tempDataProvider = _serviceProvider.GetService(typeof(ITempDataProvider)) as ITempDataProvider;



                        if (engine == null)

                        {

                            throw new Exception("Can't find IRazorViewEngine");

                        }





                        var viewEngineResult = engine.FindView(actionContext, viewPath, false);



                        if (!viewEngineResult.Success)

                        {

                            throw new InvalidOperationException($"Couldn't find view '{viewName}'");

                        }



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

                        {

                            Model = model

                        };





                        using (var output = new StringWriter())

                        {

                            var viewContext = new ViewContext(actionContext, viewEngineResult.View,

                                viewDictionary, new TempDataDictionary(actionContext.HttpContext, tempDataProvider),

                                output, new HtmlHelperOptions());



                            viewEngineResult.View.RenderAsync(viewContext).GetAwaiter().GetResult();



                            return output.ToString();

                        }







                    }

                }

            }

then to load the partial view that was created from a view component, execute the method as follows:

             var stockLevelLabel = _viewRenderService.RenderToString("stocklevel", orderItem.ProductId, "_OrderDetailsStocklevel");