I've been reading over several of the questions similar to this, dealing with customizing the #Html.ValidationMessageFor but none of them touched on what I'm looking to do.
The current form I'm working on is editing a user in a database. Within this form I need to check that the email being entered is not already used for another user. I have the logic, but what I don't have is the custom validation message to appear on the page if they use an already in-use email.
Controller code:
[HttpPost]
public ActionResult EditUser(int id, EditUserModel model)
{
if (ModelState.IsValid)
{
tbl_Users editedUser = tblUsers.EditUser(id, model, HttpContext.User.Identity.Name);
tblHSDA.EditHSDAS(id, editedUser, model.hsdas, HttpContext.User.Identity.Name);
return Redirect("~/UserManage/ListActiveUsers");
}
if (tblUsers.ValidateEmailInUse(model.Email))
{
// change validation message and return View(model);
}
tbl_Users tbl_users = db.tbl_Users.SingleOrDefault(item => item.User_id == id);
ViewBag.hsdas = tblHSDA.GetHSDANameAlpha();
ViewBag.Username = tbl_users.Username;
return View(model);
}
Is this something done at the Controller level?
as per your logic the email check part will never execute if the user fills in the form correctly and provides a duplicate email
what you can do is change the ActionResult like
[HttpPost]
public ActionResult EditUser(int id, EditUserModel model)
{
if (ModelState.IsValid)
{
if(!CheckEmail(model.Email)){
tbl_Users editedUser = tblUsers.EditUser(id, model, HttpContext.User.Identity.Name);
tblHSDA.EditHSDAS(id, editedUser, model.hsdas, HttpContext.User.Identity.Name);
return Redirect("~/UserManage/ListActiveUsers");
}else{
ModelState.AddModelError("Email","Email provided is already in use...")
}
}
tbl_Users tbl_users = db.tbl_Users.SingleOrDefault(item => item.User_id == id);
ViewBag.hsdas = tblHSDA.GetHSDANameAlpha();
ViewBag.Username = tbl_users.Username;
return View(model);
}
private bool CheckEmail(string email){
//email check logic
// return true or false
}
also have a look at http://msdn.microsoft.com/en-us/library/gg508808%28v=vs.98%29.aspx
Related
how can i send data between actions with redirectAction??
I am using PRG pattern. And I want to make something like that
[HttpGet]
[ActionName("Success")]
public ActionResult Success(PersonalDataViewModel model)
{
//model ko
if (model == null)
return RedirectToAction("Index", "Account");
//model OK
return View(model);
}
[HttpPost]
[ExportModelStateToTempData]
[ActionName("Success")]
public ActionResult SuccessProcess(PersonalDataViewModel model)
{
if (!ModelState.IsValid)
{
ModelState.AddModelError("", "Error");
return RedirectToAction("Index", "Account");
}
//model OK
return RedirectToAction("Success", new PersonalDataViewModel() { BadgeData = this.GetBadgeData });
}
When redirect you can only pass query string values. Not entire complex objects:
return RedirectToAction("Success", new {
prop1 = model.Prop1,
prop2 = model.Prop2,
...
});
This works only with scalar values. So you need to ensure that you include every property that you need in the query string, otherwise it will be lost in the redirect.
Another possibility is to persist your model somewhere on the server (like a database or something) and when redirecting only pass the id which will allow to retrieve the model back:
int id = StoreModel(model);
return RedirectToAction("Success", new { id = id });
and inside the Success action retrieve the model back:
public ActionResult Success(int id)
{
var model = GetModel(id);
...
}
Yet another possibility is to use TempData although personally I don't recommend it:
TempData["model"] = model;
return RedirectToAction("Success");
and inside the Success action fetch it from TempData:
var model = TempData["model"] as PersonalDataViewModel;
You cannot pass data between actions using objects, as Darin mentioned, you can only pass scalar values.
If your data is too large, or does not consist only of scalar values, you should do something like this
[HttpGet]
public ActionResult Success(int? id)
{
if (!(id.HasValue))
return RedirectToAction("Index", "Account");
//id OK
model = LoadModelById(id.Value);
return View(model);
}
And pass that id from RedirectToAction
return RedirectToAction("Success", { id = Model.Id });
RedirectToAction method returns an HTTP 302 response to the browser, which causes the browser to make a GET request to the specified action. So you can not pass complex objects like you calling other methods with complex objects.
Your possible solution is to pass an id using with the GET action can build the object again. Some thing like this
[HttpPost]
public ActionResult SuccessProcess(PersonViewModel model)
{
//Some thing is Posted (P)
if(ModelState.IsValid)
{
//Save the data and Redirect (R)
return RedirectToAction("Index",new { id=model.ID});
}
return View(model)
}
public ActionResult Index(int id)
{
//Lets do a GET (G) request like browser requesting for any time with ID
PersonViewModel model=GetPersonFromID(id);
return View(id);
}
}
You can keep data (The complex object) between This Post and GET request using Session also (TempData is internally using session even). But i believe that Takes away the purity of PRG Pattern.
I'm getting an error with TryUpdateModel when the field doesn't have a value and it's not nullable in the database. If I change the field in the database to nullable, it works. Anybody know a fix to get this to work with non nullable fields? I'm new to MVC, so I'm just playing with a tutorial to try to understand it....
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Add(FormCollection form)
{
var movieToAdd = new Movies();
if (Request != null && Request.Form != null && Request.Form.HasKeys() && ValueProvider == null)
{
ValueProvider = new FormCollection(Request.Form).ToValueProvider();
}
//Deserialize (Include white list!)
TryUpdateModel(movieToAdd, new string[] { "Title", "Director" }, form.ToValueProvider());
// Validate
if (string.IsNullOrEmpty(movieToAdd.Title))
ModelState.AddModelError("Title", "Title is required!");
if (string.IsNullOrEmpty(movieToAdd.Director))
ModelState.AddModelError("Director", "Director is required!");
// If valid, save movie to database
if (ModelState.IsValid)
{
_db.AddToMovies1(movieToAdd);
_db.SaveChanges();
return RedirectToAction("Index");
}
// Otherwise, reshow form
return View(movieToAdd);
}
There are a few things I would change.
Modify your method signature to accept the strongly typed model that your ActionResult is expecting. From there you can check if the Model is valid or not and continue with saving to the database
Use strongly typed models and data annotations for validating your model
EG:
Create a model which you would use for the form Get And Post actions:
public class YourModel
{
[Required]
public string Title {get; set;]
[Required]
public string Director {get; set;}
}
Your Post ActionResult then becomes:
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Add(YourModel postedform)
{
// If valid, save movie to database
if (ModelState.IsValid)
{
_db.AddToMovies1(postedform);
_db.SaveChanges();
return RedirectToAction("Index");
}
// Otherwise, reshow form
return View(postedform);
}
Here's my code:
[HttpGet]
public ActionResult Register()
{
RegisterViewModel model = new RegisterViewModel();
using (CityRepository city = new CityRepository())
{
model.SelectCityList = new SelectList(city.FindAllCities().ToList(), "CityID", "CityName");
}
using (CountryRepository country = new CountryRepository())
{
model.SelectCountryList = new SelectList(country.FindAllCountries().ToList(), "CountryID", "CountryName");
}
return View(model);
}
[HttpPost]
public ActionResult Register(RegisterViewModel model)
{
if (ModelState.IsValid)
{
//Actually register the user here.
RedirectToAction("Index", "Home");
}
//Something went wrong, redisplay the form for correction.
return View(model);
}
Is this the best approach or is there another better tested way? Keep in mind that my database tables/field names are nothing like what I declared in my models. I have to scrape the values from the ViewModel and put them into an entity framework generated class to persist the information.
Anything here that screams out at you as wrong?
I use that pattern and another pattern which looks like this (important part is the AutoMapper part):
[HttpPost]
public ActionResult Register(RegisterViewModel model)
{
if (!ModelState.IsValid)
{
// repopulate any input or other items set in GET
// prefer to do at top due to ^^^ is easy to overlook
return View(model);
}
// if it's an edit, pull to new instance
// from the database and use automapper to
// map over the submitted values from model to instance
// then update instance in database
//
// VALUE: useful if form only shows
// some of the properties/fields of model
// (otherwise, those not shown would be null/default)
// if it's new, insert
RedirectToAction("Index", "Home");
}
That's the pattern I generally use.
I prefer this pattern:
Controller:
[HttpGet]
public ActionResult Index()
{
var cities= (from m in db.cities select m);
ViewBag.Cities= cities;
var states = (from m in db.States select m);
ViewBag.States = states;
return View();
}
[HttpPost]
public ActionResult Index(RegisterViewModel model)
{
if (ModelState.IsValid)
{
// Saving the data
return View("ActionName", model);
}
return View();
}
View:
#Html.DropDownList("DDLCities",new SelectList(ViewBag.Cities, "CityId" , "CityName" ), new { #class = "className" })
#Html.DropDownList("DDLStates",new SelectList(ViewBag.States, "StateId" , "StateName" ), new { #class = "className" })
Advised changes to [HttpGet]:
[HttpGet]
public ActionResult Register()
{
// Get
var cities = new List<City>();
var countries = new List<Country>();
using (CityRepository city = new CityRepository())
{
cities = city.FindAllCities().ToList();
}
using (CountryRepository country = new CountryRepository())
{
counties = country.FindAllCountries().ToList();
}
// Map.
var aggregatedObjects = new SomePOCO(cities, countries);
var model = Mapper.Map<SomePOCO,RegisterViewModel>(aggregatedObjects );
// Return
return View(model);
}
Summary of changes:
Layout your logic in such a way the controller's job makes sense. Get - Map - Return. Exactly the tasks (in order) for which a Controller is designed for.
Use AutoMapper to do the heavy lifting of ViewModel creation for you.
Advised changes to your [HttpPost]:
[HttpPost]
public ActionResult Register(RegisterViewModel model)
{
if (!ModelState.IsValid)
return View(model);
try
{
var dbObj = Mapper.Map<RegisterViewModel,SomeDomainObj>(model);
_repository.Save(dbObj);
return RedirectToAction("Index");
}
catch (Exception exc)
{
if (exc is BusinessError)
ModelState.AddModelError("SomeKey", ((BusinessError)exc).FriendlyError);
else
ModelState.AddModelError("SomeKey", Resources.Global.GenericErrorMessage);
}
return View(model);
}
Summary of changes:
Try/catch. Always need to capture exceptions, whether they are domain exceptions or lower-level (database ones)
Check ModelState validity first. As #Cymen says - do it first so you don't forget later
Add exceptions to ModelState. Use custom exception classes for business errors with descriptive, resource-based messages. If the error is too low-level for the user (foreign key constraint, etc), show a generic message
If I have the usual Edit actions, one for GET to retrieve an object by it's ID and to display it in an edit form. The next for POST to take the values in the ViewModel and update the object in the database.
public virtual ActionResult Edit(int id)
[HttpPost]
public ActionResult Edit(VehicleVariantEditSaveViewModel viewModel)
If an error occurs during model binding in the POST action, I understand I can RedirectToAction back to the GET action and preserve the ModelState validation errors by copying it to TempData and retrieving it after the redirect in the GET action.
if (TempData["ViewData"] != null)
{
ViewData = (ViewDataDictionary)TempData["ViewData"];
}
How do I then convert that ViewData, which includes the previous invalid ModelState, into a new model to send to the view so the user sees their invalid input with validation warnings? Oddly enough if I pass in a new instance of my ViewModel retrieved from the database (with the original valid data) to the View() this is ignored and the (invalid) data in the ViewData is displayed!
Thanks
I had a similar problem and decided to use the following pattern:
public ActionResult PersonalRecord(Guid id)
{
if (TempData["Model"] == null)
{
var personalRecord = _context.PersonalRecords.Single(p => p.UserId == id);
var model = personalRecord.ToPersonalRecordModel();
return View(model);
}
else
{
ViewData = (ViewDataDictionary) TempData["ViewData"];
return View(TempData["Model"]);
}
}
[HttpPost]
public ActionResult PersonalRecord(PersonalRecordModel model)
{
try
{
if (ModelState.IsValid)
{
var personalRecord = _context.PersonalRecords.Single(u => u.UserId == model.UserId);
personalRecord.Email = model.Email;
personalRecord.DOB = model.DOB;
personalRecord.PrimaryPhone = model.PrimaryPhone;
_context.Update(personalRecord);
_context.SaveChanges();
return RedirectToAction("PersonalRecord");
}
}
catch (DbEntityValidationException ex)
{
var errors = ex.EntityValidationErrors.First();
foreach (var propertyError in errors.ValidationErrors)
{
ModelState.AddModelError(propertyError.PropertyName, propertyError.ErrorMessage);
}
}
TempData["Model"] = model;
TempData["ViewData"] = ViewData;
return RedirectToAction("PersonalRecord", new { id = model.UserId });
}
Hope this helps.
I noticed that the Model is included in ViewData so you don't need to pass it in addition to the ViewData, what I don't understand is how you get at it to then return it to the view.
public ViewResult Edit(int id)
{
// Check if we have ViewData in the session from a previous attempt which failed validation
if (TempData["ViewData"] != null)
{
ViewData = (ViewDataDictionary)TempData["ViewData"];
}
VehicleVariantEditViewModel viewModel = new VehicleVariantControllerViewModelBuilder()
.BuildForEdit(id);
return View(viewModel);
}
The above works but obviously it's making an unnecessary call to the database to build a new Model (which gets automagically overwritten with the invalid values from the Model in the passed ViewData)
Confusing.
I'm a beginner of MVC3 with ASP.Net (C#) but I don't get the next situation to delete a record.
I have a View that ask the user to confirm delete a item (record). As code I have this to initialize the view:
public ActionResult KeywordsDelete(Guid id)
{
_db = new BlaContext();
return _db.SearchTerms.Where(x => x.id.Equals(id)).First();
}
But when confirmed, then I have the next code.
[HttpPost]
public ActionResult KeywordsDelete(Guid id)
{
_db = new BlaContext();
var term = _db.SearchTerms.Where(x => x.id == id).First();
_db.SearchTerms.Remove(term);
_db.SaveChanges();
return View("Keywords", _db.SearchTerms.ToList());
}
Building is not possible because the signature of this method is already exists (same parameters and method name).
So I don't get how to delete a record in this situation. The view is created with a default Scaffold template (delete).
I found an alternative solution to this problem while reading up on MVC. Check out: Improving the Details and Delete Methods
[HttpPost, ActionName("Delete")]
public ActionResult DeleteConfirmed(int id = 0)
{
// Delete stuff...
}
This will route the action Delete to the method DeleteConfirmed.
You can give your post function another additional parameter
[HttpPost]
public ActionResult KeywordsDelete(Guid id, FormCollection collection)
{
_db = new BlaContext();
var term = _db.SearchTerms.Where(x => x.id == id).First();
_db.SearchTerms.Remove(term);
_db.SaveChanges();
return View("Keywords", _db.SearchTerms.ToList());
}
But your GET Action should also return a View not a data object, I think.
public ActionResult KeywordsDelete(Guid id)
{
_db = new BlaContext();
return View(_db.SearchTerms.Where(x => x.id.Equals(id)).First());
}