Inconvenient to upload files to the server and use TempData - asp.net-mvc

I'm trying to make a file upload to the server using Uploadify, but not working the TempData to pass variables between controllers and I have not found an error.
I'm trying passing the variables fileName and file with TempData of the controller "GetFile" to the controller "ModelCreate".
The controller "GetFile" works well, but when I check the value of "date1" and "date2" in the controller "ModelCreate" is null
I just want to make the file saved in the controller "ModelCreate"
public string GetFile(HttpPostedFileBase file)
{
var fileName = this.Server.MapPath("~/Informs/" + System.IO.Path.GetFileName(file.FileName));
if (System.IO.File.Exists(fileName))
return "has been uploaded successfully";
file.SaveAs(fileName);
TempData["NameFile"] = fileName;
TempData["File"] = file;
return "1";
}
[HttpPost]
public ActionResult ModelCreate(INFORME inform)
{
var date1 = TempData["NameFile"] as string;
var date2 = TempData["File"] as HttpPostedFileBase;
date2.SaveAs(date1);
.
.
.
.
}
why "date1" and "date2" are null?
Blessings

There's not enough information to provide an answer to this question. As requested in the comments section I will provide a full example illustrating a form allowing the user to fill a couple of input fields and upload a file.
As always we start by defining the view model which will reflect the information that we want to display on the view:
public class MyViewModel
{
[Required]
public string TextField { get; set; }
[DataType(DataType.MultilineText)]
public string TextAreaField { get; set; }
public bool CheckBoxField { get; set; }
[Required]
public HttpPostedFileBase FileField { get; set; }
}
Then we could have a controller with 2 actions: a GET action that simply displays the form and a POST action that processes the form information when submitted:
public class HomeController : Controller
{
public ActionResult Index()
{
var model = new MyViewModel();
return View(model);
}
[HttpPost]
public ActionResult Index(MyViewModel model)
{
if (!ModelState.IsValid)
{
// there were validation errors => redisplay the view
return View(model);
}
// at this stage the model is valid => we could do some processing
// first let's save the file
var appData = Server.MapPath("~/app_data");
var file = Path.Combine(appData, Path.GetFileName(model.FileField.FileName));
model.FileField.SaveAs(file);
// then we could process the other properties
// ...
return Content("Thanks for submitting the data");
}
}
and finally a strongly typed view top the view model:
#model MyViewModel
#Html.ValidationSummary(false)
#using (Html.BeginForm(null, null, FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<div>
#Html.EditorFor(x => x.TextField)
#Html.ValidationMessageFor(x => x.TextField)
</div>
<div>
#Html.EditorFor(x => x.TextAreaField)
#Html.ValidationMessageFor(x => x.TextAreaField)
</div>
<div>
#Html.CheckBoxFor(x => x.CheckBoxField)
#Html.ValidationMessageFor(x => x.CheckBoxField)
</div>
<div>
#Html.LabelFor(x => x.FileField)
#Html.TextBoxFor(x => x.FileField, new { type = "file" })
</div>
<button type="submit">OK</button>
}

Related

Null object from view in ASP.NET MVC Form

I'm building a simple inventory application where the user create an order by selecting the items he wants to be delivered, fill a form with the name of the recipient and then the order get processed.
First of all I have an OrdineScarico class that stores a collection of InventoryItems to be processed (like a cart), a DeliverDetails class that stores the recipient name
public class OrdineScarico
{
private List<SingoloOrdine> ordineCollection = new List<SingoloOrdine>();
// collection methods
}
public class SingoloOrdine
{
public InventoryItem InventoryItem { get; set; }
public int Qty { get; set; }
}
public class DeliverDetails
{
[Required(ErrorMessage = "Inserire il nome del ricevente")]
public string Nome { get; set; }
}
and then a ConfermaScaricoViewModel class -in a different namespace- for wrapping them up
public class ConfermaScaricoViewModel
{
public OrdineScarico OrdineScarico { get; set; }
public DeliverDetails DeliverDetails { get; set; }
}
I have these action methods in the ScaricoController
public ViewResult Conferma()
{
return View(
new ConfermaScaricoViewModel
{
OrdineScarico = GetScarico(),
DeliverDetails = new DeliverDetails()
});
}
[HttpPost]
public ViewResult Conferma(ConfermaScaricoViewModel viewModel)
{
if (ModelState.IsValid)
{
repositoryProcessor.ScaricaItem(viewModel.OrdineScarico, viewModel.DeliverDetails);
viewModel.OrdineScarico.Clear();
return View("Confermato");
}
else
{
return View(
new ConfermaScaricoViewModel
{
OrdineScarico = GetScarico(),
DeliverDetails = new DeliverDetails()
});
}
}
where GetScarico() reads the OrdineScarico instance from the active session
private OrdineScarico GetScarico()
{
OrdineScarico scarico = (OrdineScarico)Session["Scarico"];
if (scarico == null)
{
scarico = new OrdineScarico();
Session["Scarico"] = scarico;
}
return scarico;
}
This is the view code:
#model GestioneMagazzino.WebUI.Models.ConfermaScaricoViewModel
#{
ViewBag.Title = "Conferma";
}
<h2>Conferma scarico</h2>
#using (Html.BeginForm())
{
#Html.ValidationSummary()
<div class="form-group col-md-12">
<div class="row">
<label class="text-left">Ricevente:</label>
</div>
<div class="row">
#Html.TextBoxFor(model => model.DeliverDetails.Nome, new { #class="col-md-7" })
</div>
</div>
<div>
<input class="btn btn-primary" type="submit" value="Conferma" />
</div>
}
The problem is that when the POST action method is called, I get a null value for the OrdineScarico argument, and the ModelState is always false. I also tried adding an hidden field
#Html.HiddenFor(model => model.OrdineScarico)
but the OrdineScarico argument is always null when the POST method is called, while it's not when the controller renders the view.
Thanks,
Davide.
you must use #Html.HiddenFor(model => model.OrdineScarico)
also may be DeliverDetails has other field that you must set value for it.
you can use break point on line :
if (ModelState.IsValid)
in method post of Conferma.
run code and when code arrived to break point,
move cursor to the ModelState and wait to see data in it.
on values check all entities and find which property has error and you can see the message of error.
edit: cause you have not send any data for OrdineScarico. so it will be null in post action.
the OrdineScarico has a list member so
you should add this.
<input hidden name="OrdineScarico.ordineCollection[]" value="#value">

pass multiple models data from controller to view MVC C# [duplicate]

I want to have 2 models in one view. The page contains both LoginViewModel and RegisterViewModel.
e.g.
public class LoginViewModel
{
public string Email { get; set; }
public string Password { get; set; }
}
public class RegisterViewModel
{
public string Name { get; set; }
public string Email { get; set; }
public string Password { get; set; }
}
Do I need to make another ViewModel which holds these 2 ViewModels?
public BigViewModel
{
public LoginViewModel LoginViewModel{get; set;}
public RegisterViewModel RegisterViewModel {get; set;}
}
I need the validation attributes to be brought forward to the view. This is why I need the ViewModels.
Isn't there another way such as (without the BigViewModel):
#model ViewModel.RegisterViewModel
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(model => model.Name)
#Html.TextBoxFor(model => model.Email)
#Html.PasswordFor(model => model.Password)
}
#model ViewModel.LoginViewModel
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(model => model.Email)
#Html.PasswordFor(model => model.Password)
}
There are lots of ways...
with your BigViewModel
you do:
#model BigViewModel
#using(Html.BeginForm()) {
#Html.EditorFor(o => o.LoginViewModel.Email)
...
}
you can create 2 additional views
Login.cshtml
#model ViewModel.LoginViewModel
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(model => model.Email)
#Html.PasswordFor(model => model.Password)
}
and register.cshtml same thing
after creation you have to render them in the main view and pass them the viewmodel/viewdata
so it could be like this:
#{Html.RenderPartial("login", ViewBag.Login);}
#{Html.RenderPartial("register", ViewBag.Register);}
or
#{Html.RenderPartial("login", Model.LoginViewModel)}
#{Html.RenderPartial("register", Model.RegisterViewModel)}
using ajax parts of your web-site become more independent
iframes, but probably this is not the case
I'd recommend using Html.RenderAction and PartialViewResults to accomplish this; it will allow you to display the same data, but each partial view would still have a single view model and removes the need for a BigViewModel
So your view contain something like the following:
#Html.RenderAction("Login")
#Html.RenderAction("Register")
Where Login & Register are both actions in your controller defined like the following:
public PartialViewResult Login( )
{
return PartialView( "Login", new LoginViewModel() );
}
public PartialViewResult Register( )
{
return PartialView( "Register", new RegisterViewModel() );
}
The Login & Register would then be user controls residing in either the current View folder, or in the Shared folder and would like something like this:
/Views/Shared/Login.cshtml: (or /Views/MyView/Login.cshtml)
#model LoginViewModel
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(model => model.Email)
#Html.PasswordFor(model => model.Password)
}
/Views/Shared/Register.cshtml: (or /Views/MyView/Register.cshtml)
#model ViewModel.RegisterViewModel
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(model => model.Name)
#Html.TextBoxFor(model => model.Email)
#Html.PasswordFor(model => model.Password)
}
And there you have a single controller action, view and view file for each action with each totally distinct and not reliant upon one another for anything.
Another way is to use:
#model Tuple<LoginViewModel,RegisterViewModel>
I have explained how to use this method both in the view and controller for another example: Two models in one view in ASP MVC 3
In your case you could implement it using the following code:
In the view:
#using YourProjectNamespace.Models;
#model Tuple<LoginViewModel,RegisterViewModel>
#using (Html.BeginForm("Login1", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(tuple => tuple.Item2.Name, new {#Name="Name"})
#Html.TextBoxFor(tuple => tuple.Item2.Email, new {#Name="Email"})
#Html.PasswordFor(tuple => tuple.Item2.Password, new {#Name="Password"})
}
#using (Html.BeginForm("Login2", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(tuple => tuple.Item1.Email, new {#Name="Email"})
#Html.PasswordFor(tuple => tuple.Item1.Password, new {#Name="Password"})
}
Note that I have manually changed the Name attributes for each property when building the form. This needs to be done, otherwise it wouldn't get properly mapped to the method's parameter of type model when values are sent to the associated method for processing. I would suggest using separate methods to process these forms separately, for this example I used Login1 and Login2 methods. Login1 method requires to have a parameter of type RegisterViewModel and Login2 requires a parameter of type LoginViewModel.
if an actionlink is required you can use:
#Html.ActionLink("Edit", "Edit", new { id=Model.Item1.Id })
in the controller's method for the view, a variable of type Tuple needs to be created and then passed to the view.
Example:
public ActionResult Details()
{
var tuple = new Tuple<LoginViewModel, RegisterViewModel>(new LoginViewModel(),new RegisterViewModel());
return View(tuple);
}
or you can fill the two instances of LoginViewModel and RegisterViewModel with values and then pass it to the view.
Use a view model that contains multiple view models:
namespace MyProject.Web.ViewModels
{
public class UserViewModel
{
public UserDto User { get; set; }
public ProductDto Product { get; set; }
public AddressDto Address { get; set; }
}
}
In your view:
#model MyProject.Web.ViewModels.UserViewModel
#Html.LabelFor(model => model.User.UserName)
#Html.LabelFor(model => model.Product.ProductName)
#Html.LabelFor(model => model.Address.StreetName)
Do I need to make another view which holds these 2 views?
Answer:No
Isn't there another way such as (without the BigViewModel):
Yes, you can use Tuple (brings magic in view having multiple model).
Code:
#model Tuple<LoginViewModel, RegisterViewModel>
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(tuple=> tuple.Item.Name)
#Html.TextBoxFor(tuple=> tuple.Item.Email)
#Html.PasswordFor(tuple=> tuple.Item.Password)
}
#using (Html.BeginForm("Login", "Auth", FormMethod.Post))
{
#Html.TextBoxFor(tuple=> tuple.Item1.Email)
#Html.PasswordFor(tuple=> tuple.Item1.Password)
}
Add this ModelCollection.cs to your Models
using System;
using System.Collections.Generic;
namespace ModelContainer
{
public class ModelCollection
{
private Dictionary<Type, object> models = new Dictionary<Type, object>();
public void AddModel<T>(T t)
{
models.Add(t.GetType(), t);
}
public T GetModel<T>()
{
return (T)models[typeof(T)];
}
}
}
Controller:
public class SampleController : Controller
{
public ActionResult Index()
{
var model1 = new Model1();
var model2 = new Model2();
var model3 = new Model3();
// Do something
var modelCollection = new ModelCollection();
modelCollection.AddModel(model1);
modelCollection.AddModel(model2);
modelCollection.AddModel(model3);
return View(modelCollection);
}
}
The View:
enter code here
#using Models
#model ModelCollection
#{
ViewBag.Title = "Model1: " + ((Model.GetModel<Model1>()).Name);
}
<h2>Model2: #((Model.GetModel<Model2>()).Number</h2>
#((Model.GetModel<Model3>()).SomeProperty
a simple way to do that
we can call all model first
#using project.Models
then send your model with viewbag
// for list
ViewBag.Name = db.YourModel.ToList();
// for one
ViewBag.Name = db.YourModel.Find(id);
and in view
// for list
List<YourModel> Name = (List<YourModel>)ViewBag.Name ;
//for one
YourModel Name = (YourModel)ViewBag.Name ;
then easily use this like Model
My advice is to make a big view model:
public BigViewModel
{
public LoginViewModel LoginViewModel{get; set;}
public RegisterViewModel RegisterViewModel {get; set;}
}
In your Index.cshtml, if for example you have 2 partials:
#addTagHelper *,Microsoft.AspNetCore.Mvc.TagHelpers
#model .BigViewModel
#await Html.PartialAsync("_LoginViewPartial", Model.LoginViewModel)
#await Html.PartialAsync("_RegisterViewPartial ", Model.RegisterViewModel )
and in controller:
model=new BigViewModel();
model.LoginViewModel=new LoginViewModel();
model.RegisterViewModel=new RegisterViewModel();
I want to say that my solution was like the answer provided on this stackoverflow page: ASP.NET MVC 4, multiple models in one view?
However, in my case, the linq query they used in their Controller did not work for me.
This is said query:
var viewModels =
(from e in db.Engineers
select new MyViewModel
{
Engineer = e,
Elements = e.Elements,
})
.ToList();
Consequently, "in your view just specify that you're using a collection of view models" did not work for me either.
However, a slight variation on that solution did work for me. Here is my solution in case this helps anyone.
Here is my view model in which I know I will have just one team but that team may have multiple boards (and I have a ViewModels folder within my Models folder btw, hence the namespace):
namespace TaskBoard.Models.ViewModels
{
public class TeamBoards
{
public Team Team { get; set; }
public List<Board> Boards { get; set; }
}
}
Now this is my controller. This is the most significant difference from the solution in the link referenced above. I build out the ViewModel to send to the view differently.
public ActionResult Details(int? id)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
TeamBoards teamBoards = new TeamBoards();
teamBoards.Boards = (from b in db.Boards
where b.TeamId == id
select b).ToList();
teamBoards.Team = (from t in db.Teams
where t.TeamId == id
select t).FirstOrDefault();
if (teamBoards == null)
{
return HttpNotFound();
}
return View(teamBoards);
}
Then in my view I do not specify it as a list. I just do "#model TaskBoard.Models.ViewModels.TeamBoards" Then I only need a for each when I iterate over the Team's boards. Here is my view:
#model TaskBoard.Models.ViewModels.TeamBoards
#{
ViewBag.Title = "Details";
}
<h2>Details</h2>
<div>
<h4>Team</h4>
<hr />
#Html.ActionLink("Create New Board", "Create", "Board", new { TeamId = #Model.Team.TeamId}, null)
<dl class="dl-horizontal">
<dt>
#Html.DisplayNameFor(model => Model.Team.Name)
</dt>
<dd>
#Html.DisplayFor(model => Model.Team.Name)
<ul>
#foreach(var board in Model.Boards)
{
<li>#Html.DisplayFor(model => board.BoardName)</li>
}
</ul>
</dd>
</dl>
</div>
<p>
#Html.ActionLink("Edit", "Edit", new { id = Model.Team.TeamId }) |
#Html.ActionLink("Back to List", "Index")
</p>
I am fairly new to ASP.NET MVC so it took me a little while to figure this out. So, I hope this post helps someone figure it out for their project in a shorter timeframe. :-)
Create one new class in your model and properties of LoginViewModel and RegisterViewModel:
public class UserDefinedModel()
{
property a1 as LoginViewModel
property a2 as RegisterViewModel
}
Then use UserDefinedModel in your view.
you can always pass the second object in a ViewBag or View Data.
This is a simplified example with IEnumerable.
I was using two models on the view: a form with search criteria (SearchParams model), and a grid for results, and I struggled with how to add the IEnumerable model and the other model on the same view. Here is what I came up with, hope this helps someone:
#using DelegatePortal.ViewModels;
#model SearchViewModel
#using (Html.BeginForm("Search", "Delegate", FormMethod.Post))
{
Employee First Name
#Html.EditorFor(model => model.SearchParams.FirstName,
new { htmlAttributes = new { #class = "form-control form-control-sm " } })
<input type="submit" id="getResults" value="SEARCH" class="btn btn-primary btn-lg btn-block" />
}
<br />
#(Html
.Grid(Model.Delegates)
.Build(columns =>
{
columns.Add(model => model.Id).Titled("Id").Css("collapse");
columns.Add(model => model.LastName).Titled("Last Name");
columns.Add(model => model.FirstName).Titled("First Name");
})
...
)
SearchViewModel.cs:
namespace DelegatePortal.ViewModels
{
public class SearchViewModel
{
public IEnumerable<DelegatePortal.Models.DelegateView> Delegates { get; set; }
public SearchParamsViewModel SearchParams { get; set; }
....
DelegateController.cs:
// GET: /Delegate/Search
public ActionResult Search(String firstName)
{
SearchViewModel model = new SearchViewModel();
model.Delegates = db.Set<DelegateView>();
return View(model);
}
// POST: /Delegate/Search
[HttpPost]
public ActionResult Search(SearchParamsViewModel searchParams)
{
String firstName = searchParams.FirstName;
SearchViewModel model = new SearchViewModel();
if (firstName != null)
model.Delegates = db.Set<DelegateView>().Where(x => x.FirstName == firstName);
return View(model);
}
SearchParamsViewModel.cs:
namespace DelegatePortal.ViewModels
{
public class SearchParamsViewModel
{
public string FirstName { get; set; }
}
}

How do I get a strongly typed DropDownList to bind to a control Action

I've just started a new MVC project and I'm having trouble getting the post result from a form.
This is my Model Class :
public class User
{
public int id { get; set; }
public string name { get; set; }
}
public class TestModel
{
public List<User> users { get; set; }
public User user { get; set; }
public SelectList listSelection { get; set; }
public TestModel()
{
users = new List<User>()
{
new User() {id = 0, name = "Steven"},
new User() {id = 1, name = "Ian"},
new User() {id = 2, name = "Rich"}
};
listSelection = new SelectList(users, "name", "name");
}
}
This is my view class
#model MvcTestApplicaiton.Models.TestModel
#{
ViewBag.Title = "Index";
}
<h2>Index</h2>
#using (Html.BeginForm())
{
#Html.DropDownListFor(x => x.user, #Model.listSelection)
<p>
<input type="submit" value="Submit" />
</p>
}
#if (#Model.user != null)
{
<p>#Model.user.name</p>
}
And this is my controller :
public class TestModelController : Controller
{
public TestModel model;
//
// GET: /TestModel/
public ActionResult Index()
{
if(model ==null)
model = new TestModel();
return View(model);
}
[HttpPost]
public ActionResult Test(TestModel test)
{
model.user = test.user;
return RedirectToAction("index", "TestModel");
}
}
The drop down list appears just fine but I can't see to get the ActionResult Test function to run. I thought it would just bind itself with reflection but whatever is wrong, I can't see it.
You have two main errors in your code.
As Brett said you're posting to the Index method, but you don't have Index method that supports POST verb. The easiest way to fix is to change Html.BeginForm() with Html.BeginForm("Test", "TestModel")
You're using Html.DropDownListFor in a wrong way. You could pass only a value types there, because don't forget that the View will generate an HTML page. So instead of User in your Model you should have an UserID and in your View you should have #Html.DropDownListFor(x => x.UserID, #Model.listSelection). And finally in your Action you should query your data source to get the details for the user with this ID.
Hope this helps.
Looks like you're posting back to index. Either use a GET Test() action method, or specify the ACTION parameter in BeginForm().
For example,
#using (Html.BeginForm("Test", "TestModel"))
{
#Html.DropDownListFor(x => x.user, #Model.listSelection)
<p>
<input type="submit" value="Submit" />
</p>
}
Or use a view named Test (rename index.cshtml to test.cshtml):
public ActionResult Test()
{
if(model ==null)
model = new TestModel();
return View(model);
}

ASP.NET MVC Dropdown Selected Item

I have a DropDownListFor that is on my Index page and one in my Create page. Both dropdownlists serve the same purpose.
What I want is when the user selects an item in the Index dropdownlist in the index page, it saves that selected item's value which is a GUID to the session and when the Create page loads, I want the dropdownlist in there to select the item based on the GUID in the session.
At the moment when the user clicks on "Create" and goes to the create page, I am merely setting up an object and sending that object to the Create View.
Edit:
I am sending the user over to the Create page by doing this:
Html.ActionLink("Create New Listing", "Create", null, new { #class = "btn btn-primary" }))
How do I send the GUID of the selecteditem over to the view?
I guess you have a situation like this. Here is the Index view:
#model Models.IndexViewModel
#{
ViewBag.Title = "Index";
}
<h2>Index</h2>
#using (Html.BeginForm("SaveGuid", "Flow"))
{
Html.DropDownListFor(x => x.SelectedGuid, Model.Guids, new { onchange = "this.form.submit();" });
}
Here is the Index model:
public class IndexViewModel
{
public Guid SelectedGuid { get; set; }
public SelectList Guids { get; set; }
}
The Index and SaveGuid Action look like this:
private List<Guid> Guids = new List<Guid> { Guid.NewGuid(), Guid.NewGuid() }; // for testing only
public ActionResult Index()
{
var model = new IndexViewModel { Guids = new SelectList(Guids, Guids.First()) };
return View(model);
}
public ActionResult SaveGuid(IndexViewModel model)
{
Session["SelectedGuid"] = model.SelectedGuid;
return new RedirectResult("Create");
}
The Create View looks like this...
#model MvcBootStrapApp.Models.CreateViewModel
#{
ViewBag.Title = "Create";
}
<h2>Create</h2>
#using (Html.BeginForm("SaveGuid", "Flow"))
{
#Html.DropDownListFor(x => x.SelectedGuid, Model.Guids, new { onchange = "this.form.submit();" });
}
#using (Html.BeginForm("SaveCreate", "Flow"))
{
// setup other controls
<input type="submit" value="Submit" />
}
Using a CreateViewModel like this...
public class CreateViewModel
{
public Guid SelectedGuid { get; set; }
public SelectList Guids { get; set; }
// include other model properties
}
The Create and CreateSave ActionResults look like this...
public ActionResult Create()
{
Guid selectedGuid = Guids.First();
if (Session["SelectedGuid"] != null)
selectedGuid = (Guid)Session["SelectedGuid"];
return View(new CreateViewModel
{
Guids = new SelectList(Guids, selectedGuid),
SelectedGuid = selectedGuid
});
}
public ActionResult SaveCreate(CreateViewModel model)
{
// save properties
return new RedirectResult("Index");
}
I used two forms to allow both the change of selected Guid and to postback all the Create properties.
If you want to use Session, what I think you need is to use a form to post to an ActionResult to save the dropdownlist's value and then redirect to the Create page.
public ActionResult SaveGuid(Guid value)
{
Session["SelectedGuid"] = value;
return new RedirectResult("Create");
}
Then in your Create ActionResult, pass the Session value to the Create View's Model.
public ActionResult Create()
{
var selectedGuid = (Guid)Session["SelectedGuid"];
return View(new CreateViewModel { SelectedGuid = selectedGuid, /* include other properties */ };
}
In your view you can set the selected option on the SelectList passed to your DropDownListFor...
#Html.DropDownListFor(
x => x.SelectedGuid,
new SelectList(Model.ListOfStuff, "Key", "Value", Model.SelectedGuid)
)

Uploading Files into Database with ASP.NET MVC

I want to give a facility on my form for user to upload files and save in Database.
How is this done in ASP.NET MVC.
What DataType to write in my Model Class. I tried with Byte[], but during the scaffolding the solution could not generate the appropriate HTML for it in the corresponding View.
How are these cases handled?
You could use a byte[] on your model and a HttpPostedFileBase on your view model. For example:
public class MyViewModel
{
[Required]
public HttpPostedFileBase File { get; set; }
}
and then:
public class HomeController: Controller
{
public ActionResult Index()
{
var model = new MyViewModel();
return View(model);
}
[HttpPost]
public ActionResult Index(MyViewModel model)
{
if (!ModelState.IsValid)
{
return View(model);
}
byte[] uploadedFile = new byte[model.File.InputStream.Length];
model.File.InputStream.Read(uploadedFile, 0, uploadedFile.Length);
// now you could pass the byte array to your model and store wherever
// you intended to store it
return Content("Thanks for uploading the file");
}
}
and finally in your view:
#model MyViewModel
#using (Html.BeginForm(null, null, FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<div>
#Html.LabelFor(x => x.File)
#Html.TextBoxFor(x => x.File, new { type = "file" })
#Html.ValidationMessageFor(x => x.File)
</div>
<button type="submit">Upload</button>
}

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