Question

我有一个生成电子邮件的系统。这些电子邮件的部分内容来自ParialViews。在我的EmailController中，我希望能够通过调用它们的相关动作并插入View HTML来获取构成电子邮件模板区域的HTML代码段。

我已经在此处（Return View as String in .NET Core）上看到过有关该帖子的信息，但效果不佳...

下面的解决方案确实找到并尝试获取View HTML ，但是实际上并没有尝试执行View的controller动作。由于视图是动态的，因此会导致错误。

因此，我可以执行 ControllerB.Action，将其结果作为字符串从ControllerA.Action中检索出来吗？

我当前的尝试：服务：

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();
            }
        }
    }

Starup.cs services.AddScoped<IViewRenderService, ViewRenderService>();

控制器A

private readonly IViewRenderService _viewRenderService;
public ReportController(...
        IViewRenderService viewRenderService)
{
    ...
    _viewRenderService = viewRenderService;
}

来自控制器A的呼叫： var theHtmlString = await _viewRenderService.RenderToStringAsync("ControllerB/Action1", new { parameters = paramsmodel });

.NET Core 2.1-从ControllerA.Action执行ControllerB.Action返回一个字符串

0 个答案: