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

你可以用这种方法获取字符串中的视图

protected string RenderPartialViewToString(string viewName, object model)
{
    if (string.IsNullOrEmpty(viewName))
        viewName = ControllerContext.RouteData.GetRequiredString("action");

    if (model != null)
        ViewData.Model = model;

    using (StringWriter sw = new StringWriter())
    {
        ViewEngineResult viewResult = ViewEngines.Engines.FindPartialView(ControllerContext, viewName);
        ViewContext viewContext = new ViewContext(ControllerContext, viewResult.View, ViewData, TempData, sw);
        viewResult.View.Render(viewContext, sw);

        return sw.GetStringBuilder().ToString();
    }
}

我们可以用两种方式调用这个方法

string strView = RenderPartialViewToString("~/Views/Shared/_Header.cshtml", null)

OR

var model = new Person()
string strView = RenderPartialViewToString("~/Views/Shared/_Header.cshtml", model)

其他回答

这是我想到的,它对我很有用。我将以下方法添加到控制器基类中。(你可以在其他地方创建这些静态方法,接受控制器作为参数)

MVC2 .ascx样式

protected string RenderViewToString<T>(string viewPath, T model) {
  ViewData.Model = model;
  using (var writer = new StringWriter()) {
    var view = new WebFormView(ControllerContext, viewPath);
    var vdd = new ViewDataDictionary<T>(model);
    var viewCxt = new ViewContext(ControllerContext, view, vdd,
                                new TempDataDictionary(), writer);
    viewCxt.View.Render(viewCxt, writer);
    return writer.ToString();
  }
}

Razor .cshtml样式

public 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);
    viewResult.ViewEngine.ReleaseView(ControllerContext, viewResult.View);
    return sw.GetStringBuilder().ToString();
  }
}

编辑:添加剃刀代码。

为了重复一个更未知的问题,看一下MvcIntegrationTestFramework。

它使您节省编写自己的助手流的结果,并被证明工作得足够好。我假设这将在一个测试项目中,作为奖励,一旦您获得了这个设置,您将拥有其他测试功能。主要的麻烦可能是整理依赖链。

 private static readonly string mvcAppPath = 
     Path.GetFullPath(AppDomain.CurrentDomain.BaseDirectory 
     + "\\..\\..\\..\\MyMvcApplication");
 private readonly AppHost appHost = new AppHost(mvcAppPath);

    [Test]
    public void Root_Url_Renders_Index_View()
    {
        appHost.SimulateBrowsingSession(browsingSession => {
            RequestResult result = browsingSession.ProcessRequest("");
            Assert.IsTrue(result.ResponseText.Contains("<!DOCTYPE html"));
        });
}

我发现了一个新的解决方案,可以将视图呈现为字符串,而不必与当前HttpContext的Response流(它不允许您更改响应的ContentType或其他报头)混淆。

基本上,你所要做的就是为视图创建一个伪HttpContext来渲染它自己:

/// <summary>Renders a view to string.</summary>
public static string RenderViewToString(this Controller controller,
                                        string viewName, object viewData) {
    //Create memory writer
    var sb = new StringBuilder();
    var memWriter = new StringWriter(sb);

    //Create fake http context to render the view
    var fakeResponse = new HttpResponse(memWriter);
    var fakeContext = new HttpContext(HttpContext.Current.Request, fakeResponse);
    var fakeControllerContext = new ControllerContext(
        new HttpContextWrapper(fakeContext),
        controller.ControllerContext.RouteData,
        controller.ControllerContext.Controller);

    var oldContext = HttpContext.Current;
    HttpContext.Current = fakeContext;

    //Use HtmlHelper to render partial view to fake context
    var html = new HtmlHelper(new ViewContext(fakeControllerContext,
        new FakeView(), new ViewDataDictionary(), new TempDataDictionary()),
        new ViewPage());
    html.RenderPartial(viewName, viewData);

    //Restore context
    HttpContext.Current = oldContext;    

    //Flush memory and return output
    memWriter.Flush();
    return sb.ToString();
}

/// <summary>Fake IView implementation used to instantiate an HtmlHelper.</summary>
public class FakeView : IView {
    #region IView Members

    public void Render(ViewContext viewContext, System.IO.TextWriter writer) {
        throw new NotImplementedException();
    }

    #endregion
}

这适用于ASP。NET MVC 1.0,以及ContentResult, JsonResult等(改变原始HttpResponse上的报头不会抛出“发送HTTP报头后服务器无法设置内容类型”异常)。

更新:在ASP。NET MVC 2.0 RC,代码有一点变化,因为我们必须传入用于将视图写入ViewContext的StringWriter:

//...

//Use HtmlHelper to render partial view to fake context
var html = new HtmlHelper(
    new ViewContext(fakeControllerContext, new FakeView(),
        new ViewDataDictionary(), new TempDataDictionary(), memWriter),
    new ViewPage());
html.RenderPartial(viewName, viewData);

//...

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

快速提示

对于强类型模型,只需将其添加到ViewData。Model属性,然后传递给RenderViewToString。如

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