This will be quite simple but
What is the best way of using classical webforms "response.write" in asp net MVC. Especially mvc5.
Let's say: I just would like to write a simple string to screen from controller.
Does response.write exist in mvc?
Thanks.
If the return type of your method is an ActionResult, You can use the Content method to return any type of content.
public ActionResult MyCustomString()
{
return Content("YourStringHere");
}
or simply
public String MyCustomString()
{
return "YourStringHere";
}
Content method allows you return other content type as well, Just pass the content type as second param.
return Content("<root>Item</root>","application/xml");
As #Shyju said you should use Content method, But there's another way by creating a custom action result, Your custom action-result could look like this::
public class MyActionResult : ActionResult
{
private readonly string _content;
public MyActionResult(string content)
{
_content = content;
}
public override void ExecuteResult(ControllerContext context)
{
context.HttpContext.Response.Write(_content);
}
}
Then you can use it, this way:
public ActionResult About()
{
ViewBag.Message = "Your application description page.";
return new MyActionResult("content");
}
Related
net I am trying to take a value from a previous form typically in php it would be written like this
$name= $_POST ["Username"];
$pass= $_POST ["Password"];
how can I write this in asp.net
if you use GET
string usrnm = Request.QueryString["username"];
string pass = Request.QueryString["password"];
if you use POST
string usrnm = Request.Form["username"];
string pass = Request.Form["password"];
in web forms
if (Page.IsPostBack)
{
//access posted input as
Request.Form["input1"]
Request.Form["input2"]
Request.Form["input3"]
}
in mvc
[HttpPost]
public ActionResult myaction(strig input1,strig input1,strig input1)
{
//you can access your input here
return View();
}
or if you have view model for it, which is capable to take 3 inputs as
public class myViewmodleclass()
{
public string input1{get;set;}
public string input2{get;set;}
public string input3{get;set;}
}
controller action
[HttpPost]
public ActionResult myaction(myViewmodleclass mymodelobject)
{
//you can access your input here
return View();
}
so you using mvc, which has a nice model binding.
So you are using mvc which has nice model binding. You can simply have a proper model object. For your example
public class LoginInfo()
{
public string UserName{get;set;}
public string Password {get;set;}
}
in your controller
[HttpPost]
public ActionResult Logon(LoginInfo loginInfo )
{
// Do stuff with loginInfo
}
A lot of my plain content is in the database, accessed by a custom CMS. Around the application I display simple "thank you" messages, etc. which consist of a controller action (simplified):
public ActionResult DetailsUpdated()
{
return View();
}
and my view:
#Html.GetContent("DetailsUpdated")
I have quite a few of these and its quite annoying having a lot of view files with one-liners in. I want to be able to return that content as a View, I can do return ContentResult(ContentRepository.GetContent("KEY")); but this returns as plain-text and there is no master view rendered.
So, basically, grab the content from the DB via ContentRepository.GetContent("KEY") (returns a string) and inject it into a master view, where RenderBody() is called. I'd like to have a custom ActionResult so I can just do:
public ActionResult DetailsUpdated()
{
return DbContentResult();
}
and then the DbContentResult ActionResult will find the content key relative to the action and controller name, go to the database and retrieve the content and display it within its master view, no physical file view needed. Is this possible?
You may have one view file and refer to that view file from several actions:
public class FooBarController : Controller {
public ViewResult Foo() {
return View("FooView", ContentRepository.GetContent("KEY"));
}
}
In this case, you will be able to render the view whose path is ~/Views/Shared/FooView.cshtml (unless you override the default convention of course).
Edit:
As you indicated, you can make a custom ViewResult which does this for you:
public class DbContentResult : ViewResult {
public DbContentResult() {
this.ViewName = "FooView";
this.ViewData.Model = "Foo Model";
}
}
Usage:
public ActionResult Index() {
return new DbContentResult();
}
Or even better, write an extension method for Controller class which integrates with DbContentResult:
public static class ControllerExtensions {
public static ViewResult DbContentResult(this Controller controller) {
return new DbContentResult();
}
}
Usage:
public ActionResult Index() {
return this.DbContentResult();
}
for more detail about creating custom actionresult go here:-
http://www.professionals-helpdesk.com/2012/06/create-custom-actionresult-in-mvc-3.html
I am trying to create a custom attribute in mvc to use it's parameters in a view as breadCrumb.
well, this is the code of the attribute
[AttributeUsage(AttributeTargets.All, AllowMultiple = true)]
public class BreadCrumbAttribute : Attribute {
public BreadCrumbAttribute(string title, string parent, string url) {
this._title = title;
this._parent = parent;
this._url = url;
}
#region named parameters properties
private string _title;
public string Title {
get { return _title; }
}
private string _url;
public string Url {
get { return _url; }
}
private string _parent;
public string Parent {
get { return _parent; }
}
#endregion
#region positional parameters properties
public string Comments { get; set; }
#endregion
}
this is the call of the attribute
[BreadCrumbAttribute("tile", "parent name", "url")]
public ActionResult Index() {
//code goes here
}
this is a way of how I'd like to get the values. (this is a partial view)
System.Reflection.MemberInfo inf = typeof(ProductsController);
object[] attributes;
attributes = inf.GetCustomAttributes(typeof(BreadCrumbAttribute), false);
foreach (Object attribute in attributes) {
var bca = (BreadCrumbAttribute)attribute;
Response.Write(string.Format("{0}><a href={1}>{2}</a>", bca.Parent, bca.Url, bca.Title));
}
Unfortunately, the attribute didn't get call with the way I implement it. Although, If I add the attribute in Class instead of an Action method it worked.
How could I make it work?
Thanks
The problem is that you are using reflection to get the attributes for the class, so naturally it does not include attributes defined on the action method.
To get those, you should define an ActionFilterAttribute, and in the OnActionExecuting or OnActionExecuted method, you can use filterContext.ActionDescriptor.GetCustomAttributes() method (MSDN description here).
Note that with this solution, you will likely have two different types of attributes: The first one is the one you wrote, to define the breadcrumbs. The second is the one that looks at the attributes on the executing action and builds up the breadcrumb (and presumably adds it to the ViewModel or sticks it in HttpContext.Items or something).
If given the route:
{FeedName}/{ItemPermalink}
ex: /Blog/Hello-World
If the item doesn't exist, I want to return a 404. What is the right way to do this in ASP.NET MVC?
Shooting from the hip (cowboy coding ;-)), I'd suggest something like this:
Controller:
public class HomeController : Controller
{
public ActionResult Index()
{
return new HttpNotFoundResult("This doesn't exist");
}
}
HttpNotFoundResult:
using System;
using System.Net;
using System.Web;
using System.Web.Mvc;
namespace YourNamespaceHere
{
/// <summary>An implementation of <see cref="ActionResult" /> that throws an <see cref="HttpException" />.</summary>
public class HttpNotFoundResult : ActionResult
{
/// <summary>Initializes a new instance of <see cref="HttpNotFoundResult" /> with the specified <paramref name="message"/>.</summary>
/// <param name="message"></param>
public HttpNotFoundResult(String message)
{
this.Message = message;
}
/// <summary>Initializes a new instance of <see cref="HttpNotFoundResult" /> with an empty message.</summary>
public HttpNotFoundResult()
: this(String.Empty) { }
/// <summary>Gets or sets the message that will be passed to the thrown <see cref="HttpException" />.</summary>
public String Message { get; set; }
/// <summary>Overrides the base <see cref="ActionResult.ExecuteResult" /> functionality to throw an <see cref="HttpException" />.</summary>
public override void ExecuteResult(ControllerContext context)
{
throw new HttpException((Int32)HttpStatusCode.NotFound, this.Message);
}
}
}
// By Erik van Brakel, with edits from Daniel Schaffer :)
Using this approach you comply to the framework standards. There already is a HttpUnauthorizedResult in there, so this would simply extend the framework in the eyes of another developer maintaining your code later on (you know, the psycho who knows where you live).
You could use reflector to take a look into the assembly to see how the HttpUnauthorizedResult is achieved, because I don't know if this approach misses anything (it seems too simple almost).
I did use reflector to take a look at the HttpUnauthorizedResult just now. Seems they're setting the StatusCode on the response to 0x191 (401). Although this works for 401, using 404 as the new value I seem to be getting just a blank page in Firefox. Internet Explorer shows a default 404 though (not the ASP.NET version). Using the webdeveloper toolbar I inspected the headers in FF, which DO show a 404 Not Found response. Could be simply something I misconfigured in FF.
This being said, I think Jeff's approach is a fine example of KISS. If you don't really need the verbosity in this sample, his method works fine as well.
We do it like so; this code is found in BaseController
/// <summary>
/// returns our standard page not found view
/// </summary>
protected ViewResult PageNotFound()
{
Response.StatusCode = 404;
return View("PageNotFound");
}
called like so
public ActionResult ShowUserDetails(int? id)
{
// make sure we have a valid ID
if (!id.HasValue) return PageNotFound();
throw new HttpException(404, "Are you sure you're in the right place?");
The HttpNotFoundResult is a great first step to what I am using. Returning an HttpNotFoundResult is good. Then the question is, what's next?
I created an action filter called HandleNotFoundAttribute that then shows a 404 error page. Since it returns a view, you can create a special 404 view per controller, or let is use a default shared 404 view. This will even be called when a controller doesn't have the specified action present, because the framework throws an HttpException with a status code of 404.
public class HandleNotFoundAttribute : ActionFilterAttribute, IExceptionFilter
{
public void OnException(ExceptionContext filterContext)
{
var httpException = filterContext.Exception.GetBaseException() as HttpException;
if (httpException != null && httpException.GetHttpCode() == (int)HttpStatusCode.NotFound)
{
filterContext.HttpContext.Response.TrySkipIisCustomErrors = true; // Prevents IIS from intercepting the error and displaying its own content.
filterContext.ExceptionHandled = true;
filterContext.HttpContext.Response.StatusCode = (int) HttpStatusCode.NotFound;
filterContext.Result = new ViewResult
{
ViewName = "404",
ViewData = filterContext.Controller.ViewData,
TempData = filterContext.Controller.TempData
};
}
}
}
Note that as of MVC3, you can just use HttpStatusCodeResult.
Using ActionFilter is hard to maintain because whenever we throw an error the filter need to be set in the attribute. What if we forget to set it? One way is deriving OnException on base controller. You need to define a BaseController derived from Controller and all your controllers must derive from BaseController. It is a best practise to have a base controller.
Note if using Exception the response status code is 500, so we need to change it to 404 for Not Found and 401 for Unauthorized. Just like I mention above, use OnException overrides on BaseController to avoid using filter attribute.
The new MVC 3 also make more troublesome by returning an empty view to browser. The best solution after some research is based on my answer here How to return a view for HttpNotFound() in ASP.Net MVC 3?
To make more convinience I paste it here:
After some study. The workaround for MVC 3 here is to derive all HttpNotFoundResult, HttpUnauthorizedResult, HttpStatusCodeResult classes and implement new (overriding it) HttpNotFound() method in BaseController.
It is best practise to use base Controller so you have 'control' over all derived Controllers.
I create new HttpStatusCodeResult class, not to derive from ActionResult but from ViewResult to render the view or any View you want by specifying the ViewName property. I follow the original HttpStatusCodeResult to set the HttpContext.Response.StatusCode and HttpContext.Response.StatusDescription but then base.ExecuteResult(context) will render the suitable view because again I derive from ViewResult. Simple enough is it? Hope this will be implemented in the MVC core.
See my BaseController bellow:
using System.Web;
using System.Web.Mvc;
namespace YourNamespace.Controllers
{
public class BaseController : Controller
{
public BaseController()
{
ViewBag.MetaDescription = Settings.metaDescription;
ViewBag.MetaKeywords = Settings.metaKeywords;
}
protected new HttpNotFoundResult HttpNotFound(string statusDescription = null)
{
return new HttpNotFoundResult(statusDescription);
}
protected HttpUnauthorizedResult HttpUnauthorized(string statusDescription = null)
{
return new HttpUnauthorizedResult(statusDescription);
}
protected class HttpNotFoundResult : HttpStatusCodeResult
{
public HttpNotFoundResult() : this(null) { }
public HttpNotFoundResult(string statusDescription) : base(404, statusDescription) { }
}
protected class HttpUnauthorizedResult : HttpStatusCodeResult
{
public HttpUnauthorizedResult(string statusDescription) : base(401, statusDescription) { }
}
protected class HttpStatusCodeResult : ViewResult
{
public int StatusCode { get; private set; }
public string StatusDescription { get; private set; }
public HttpStatusCodeResult(int statusCode) : this(statusCode, null) { }
public HttpStatusCodeResult(int statusCode, string statusDescription)
{
this.StatusCode = statusCode;
this.StatusDescription = statusDescription;
}
public override void ExecuteResult(ControllerContext context)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
context.HttpContext.Response.StatusCode = this.StatusCode;
if (this.StatusDescription != null)
{
context.HttpContext.Response.StatusDescription = this.StatusDescription;
}
// 1. Uncomment this to use the existing Error.ascx / Error.cshtml to view as an error or
// 2. Uncomment this and change to any custom view and set the name here or simply
// 3. (Recommended) Let it commented and the ViewName will be the current controller view action and on your view (or layout view even better) show the #ViewBag.Message to produce an inline message that tell the Not Found or Unauthorized
//this.ViewName = "Error";
this.ViewBag.Message = context.HttpContext.Response.StatusDescription;
base.ExecuteResult(context);
}
}
}
}
To use in your action like this:
public ActionResult Index()
{
// Some processing
if (...)
return HttpNotFound();
// Other processing
}
And in _Layout.cshtml (like master page)
<div class="content">
#if (ViewBag.Message != null)
{
<div class="inlineMsg"><p>#ViewBag.Message</p></div>
}
#RenderBody()
</div>
Additionally you can use a custom view like Error.shtml or create new NotFound.cshtml like I commented in the code and you may define a view model for the status description and other explanations.
How do I Unit Test a MVC redirection?
public ActionResult Create(Product product)
{
_productTask.Save(product);
return RedirectToAction("Success");
}
public ActionResult Success()
{
return View();
}
Is Ayende's approach still the best way to go, with preview 5:
public static void RenderView(this Controller self, string action)
{
typeof(Controller).GetMethod("RenderView").Invoke(self,new object[] { action} );
}
Seems odd to have to do this, especially as the MVC team have said they are writing the framework to be testable.
[TestFixture]
public class RedirectTester
{
[Test]
public void Should_redirect_to_success_action()
{
var controller = new RedirectController();
var result = controller.Index() as RedirectToRouteResult;
Assert.That(result, Is.Not.Null);
Assert.That(result.Values["action"], Is.EqualTo("success"));
}
}
public class RedirectController : Controller
{
public ActionResult Index()
{
return RedirectToAction("success");
}
}
This works for ASP.NET MVC 5 using NUnit:
[Test]
public void ShouldRedirectToSuccessAction()
{
var controller = new RedirectController();
var result = controller.Index() as RedirectToRouteResult;
Assert.That(result.RouteValues["action"], Is.EqualTo("success"));
}
If you want to test that you are redirecting to a different controller (say NewController), the assertion would be:
Assert.That(result.RouteValues["controller"], Is.EqualTo("New"));
You can assert on the ActionResult that is returned, you'll need to cast it to the appropriate type but it does allow you to use state-based testing. A search on the Web should find some useful links, here's just one though.
you can use Mvc.Contrib.TestHelper which provides assertions for testing redirections. Take a look at http://kbochevski.blogspot.com/2010/06/unit-testing-mvcnet.html and the code sample. It might be helpful.