我想输出两个不同的视图(一个作为字符串,将作为电子邮件发送),另一个是显示给用户的页面。

这在ASP中可能吗?NET MVC beta版?

我试过很多例子:

1. 在ASP。NET MVC Beta版

如果我使用这个例子,我会收到“HTTP后不能重定向” 报头已发送。”

2. MVC框架:捕获视图的输出

如果我使用这个,我似乎无法做一个重定向toaction,因为它 试图呈现一个可能不存在的视图。如果我返回视图 完全是一团糟,看起来一点都不对。

有人对我提出的这些问题有什么想法/解决方案吗?或者有什么更好的建议吗?

很多谢谢!

下面是一个例子。我要做的是创建GetViewForEmail方法:

public ActionResult OrderResult(string ref)
{
    //Get the order
    Order order = OrderService.GetOrder(ref);

    //The email helper would do the meat and veg by getting the view as a string
    //Pass the control name (OrderResultEmail) and the model (order)
    string emailView = GetViewForEmail("OrderResultEmail", order);

    //Email the order out
    EmailHelper(order, emailView);
    return View("OrderResult", order);
}

接受蒂姆·斯科特的回答(我做了一些修改和格式化):

public virtual string RenderViewToString(
    ControllerContext controllerContext,
    string viewPath,
    string masterPath,
    ViewDataDictionary viewData,
    TempDataDictionary tempData)
{
    Stream filter = null;
    ViewPage viewPage = new ViewPage();

    //Right, create our view
    viewPage.ViewContext = new ViewContext(controllerContext, new WebFormView(viewPath, masterPath), viewData, tempData);

    //Get the response context, flush it and get the response filter.
    var response = viewPage.ViewContext.HttpContext.Response;
    response.Flush();
    var oldFilter = response.Filter;

    try
    {
        //Put a new filter into the response
        filter = new MemoryStream();
        response.Filter = filter;

        //Now render the view into the memorystream and flush the response
        viewPage.ViewContext.View.Render(viewPage.ViewContext, viewPage.ViewContext.HttpContext.Response.Output);
        response.Flush();

        //Now read the rendered view.
        filter.Position = 0;
        var reader = new StreamReader(filter, response.ContentEncoding);
        return reader.ReadToEnd();
    }
    finally
    {
        //Clean up.
        if (filter != null)
        {
            filter.Dispose();
        }

        //Now replace the response filter
        response.Filter = oldFilter;
    }
}

示例使用

假设控制器通过Site调用订单确认电子邮件。主人的位置。

string myString = RenderViewToString(this.ControllerContext, "~/Views/Order/OrderResultEmail.aspx", "~/Views/Shared/Site.Master", this.ViewData, this.TempData);

当前回答

我从另一个网站上看到了MVC 3和Razor的实现,它对我有用:

    public static string RazorRender(Controller context, string DefaultAction)
    {
        string Cache = string.Empty;
        System.Text.StringBuilder sb = new System.Text.StringBuilder();
        System.IO.TextWriter tw = new System.IO.StringWriter(sb); 

        RazorView view_ = new RazorView(context.ControllerContext, DefaultAction, null, false, null);
        view_.Render(new ViewContext(context.ControllerContext, view_, new ViewDataDictionary(), new TempDataDictionary(), tw), tw);

        Cache = sb.ToString(); 

        return Cache;

    } 

    public static string RenderRazorViewToString(string viewName, object model)
    {

        ViewData.Model = model;
        using (var sw = new StringWriter())
        {
            var viewResult = ViewEngines.Engines.FindPartialView(ControllerContext, viewName);
            var viewContext = new ViewContext(ControllerContext, viewResult.View, ViewData, TempData, sw);
            viewResult.View.Render(viewContext, sw);
            return sw.GetStringBuilder().ToString();
        }
    } 

    public static class HtmlHelperExtensions
    {
        public static string RenderPartialToString(ControllerContext context, string partialViewName, ViewDataDictionary viewData, TempDataDictionary tempData)
        {
            ViewEngineResult result = ViewEngines.Engines.FindPartialView(context, partialViewName);

            if (result.View != null)
            {
                StringBuilder sb = new StringBuilder();
                using (StringWriter sw = new StringWriter(sb))
                {
                    using (HtmlTextWriter output = new HtmlTextWriter(sw))
                    {
                        ViewContext viewContext = new ViewContext(context, result.View, viewData, tempData, output);
                        result.View.Render(viewContext, output);
                    }
                }
                return sb.ToString();
            } 

            return String.Empty;

        }

    }

更多关于Razor渲染- MVC3视图渲染到字符串

其他回答

asp.net CORE的额外提示:

接口:

public interface IViewRenderer
{
  Task<string> RenderAsync<TModel>(Controller controller, string name, TModel model);
}

实现:

public class ViewRenderer : IViewRenderer
{
  private readonly IRazorViewEngine viewEngine;

  public ViewRenderer(IRazorViewEngine viewEngine) => this.viewEngine = viewEngine;

  public async Task<string> RenderAsync<TModel>(Controller controller, string name, TModel model)
  {
    ViewEngineResult viewEngineResult = this.viewEngine.FindView(controller.ControllerContext, name, false);

    if (!viewEngineResult.Success)
    {
      throw new InvalidOperationException(string.Format("Could not find view: {0}", name));
    }

    IView view = viewEngineResult.View;
    controller.ViewData.Model = model;

    await using var writer = new StringWriter();
    var viewContext = new ViewContext(
       controller.ControllerContext,
       view,
       controller.ViewData,
       controller.TempData,
       writer,
       new HtmlHelperOptions());

       await view.RenderAsync(viewContext);

       return writer.ToString();
  }
}

在Startup.cs中注册

...
 services.AddSingleton<IViewRenderer, ViewRenderer>();
...

在控制器中的使用:

public MyController: Controller
{
  private readonly IViewRenderer renderer;
  public MyController(IViewRendere renderer) => this.renderer = renderer;
  public async Task<IActionResult> MyViewTest
  {
    var view = await this.renderer.RenderAsync(this, "MyView", model);
    return new OkObjectResult(view);
  }
}

我发现了一个更好的方法来渲染剃刀视图页面,当我得到错误的方法上面,这个解决方案的web表单环境和mvc环境。 不需要控制器。

下面是代码示例,在这个示例中,我模拟了一个mvc动作与异步http处理程序:

    /// <summary>
    /// Enables processing of HTTP Web requests asynchronously by a custom HttpHandler that implements the IHttpHandler interface.
    /// </summary>
    /// <param name="context">An HttpContext object that provides references to the intrinsic server objects.</param>
    /// <returns>The task to complete the http request.</returns>
    protected override async Task ProcessRequestAsync(HttpContext context)
    {
        if (this._view == null)
        {
            this.OnError(context, new FileNotFoundException("Can not find the mvc view file.".Localize()));
            return;
        }
        object model = await this.LoadModelAsync(context);
        WebPageBase page = WebPageBase.CreateInstanceFromVirtualPath(this._view.VirtualPath);
        using (StringWriter sw = new StringWriter())
        {
            page.ExecutePageHierarchy(new WebPageContext(new HttpContextWrapper(context), page, model), sw);
            await context.Response.Output.WriteAsync(sw.GetStringBuilder().ToString());
        }
    }

这篇文章描述了如何在不同的场景中呈现一个视图给字符串:

MVC控制器调用它自己的另一个actionmethod MVC控制器调用另一个MVC控制器的ActionMethod WebAPI控制器调用MVC控制器的ActionMethod

解决方案/代码作为一个名为ViewRenderer的类提供。它是Rick Stahl在GitHub上的WestwindToolkit的一部分。

使用(3。- WebAPI示例):

string html = ViewRenderer.RenderView("~/Areas/ReportDetail/Views/ReportDetail/Index.cshtml", ReportVM.Create(id));

我使用的是MVC 1.0 RTM,上面的解决方案都不适合我。但这一个做到了:

Public Function RenderView(ByVal viewContext As ViewContext) As String

    Dim html As String = ""

    Dim response As HttpResponse = HttpContext.Current.Response

    Using tempWriter As New System.IO.StringWriter()

        Dim privateMethod As MethodInfo = response.GetType().GetMethod("SwitchWriter", BindingFlags.NonPublic Or BindingFlags.Instance)

        Dim currentWriter As Object = privateMethod.Invoke(response, BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.InvokeMethod, Nothing, New Object() {tempWriter}, Nothing)

        Try
            viewContext.View.Render(viewContext, Nothing)
            html = tempWriter.ToString()
        Finally
            privateMethod.Invoke(response, BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.InvokeMethod, Nothing, New Object() {currentWriter}, Nothing)
        End Try

    End Using

    Return html

End Function

如果你想完全放弃MVC,从而避免HttpContext的混乱…

using RazorEngine;
using RazorEngine.Templating; // For extension methods.

string razorText = System.IO.File.ReadAllText(razorTemplateFileLocation);
string emailBody = Engine.Razor.RunCompile(razorText, "templateKey", typeof(Model), model);

这里使用了非常棒的开源Razor Engine: https://github.com/Antaris/RazorEngine