I have this field called Mobile_Number in my class Friends
[Remote("CheckMobileDuplicate", "Friends", ErrorMessage = "This mobile number is already in use", AdditionalFields = "Friend_Id")]
public string Mobile_Number { get; set; }
Now there are 2 views in which post back occurs for the model class Friends, Create view and an edit view.
My CheckMobileDuplicate function is as follows
public JsonResult CheckMobileDuplicate(string Mobile_Number,int Friend_Id)
{
if (db.Friends.Any(x => (x.Mobile_Number == Mobile_Number) && (x.Friend_Id != Friend_Id))
return Json(false, JsonRequestBehavior.AllowGet);
else
return Json(true, JsonRequestBehavior.AllowGet);
}
Now the condition x.Friend_Id != Friend_Id
Checks if the Friend_Id already exists so when we are checking in edit view it does not compare the mobile_number to the mobile_number of the same friend in the database.
But in create the Friend_Id is undefined as the row in database table is not yet created and hence this is not working for create.
So how do I check in the function whether it is called from create view or edit view because making Friend_Id nullable is not an option ?
You should be using a view model for this. The RemoteAttribute is a view specific attribute and does not belong in a data model.
public class FriendsVM
{
public int? Friend_Id { get; set; }
[Remote("CheckMobileDuplicate", "Friends", ErrorMessage = "...", AdditionalFields = "Friend_Id")]
public string Mobile_Number { get; set; }
.... // other properties of Friend
}
and then in the view, add a hidden input for Friend_Id
#Html.HiddenFor(m => m.Friend_Id)
and modify the controller method to
public JsonResult CheckMobileDuplicate(string Mobile_Number, int? Friend_Id)
{
bool isUnique = IsUniqueMobile(Mobile_Number, Friend_Id);
return Json(isUnique, JsonRequestBehavior);
}
private bool IsUniqueMobile(string number, int? ID)
{
if (ID.hasValue) // its an existing Friend
{
return !db.Friends.Any(x => x.Mobile_Number == number && x.Friend_Id != ID.Value);
}
else // its a new Friend
{
return !db.Friends.Any(x => x.Mobile_Number == number);
}
}
Note that I have refactored the database access code into a private method, so that method can also be called in the POST method
Related
How to solve one to many relational issue in asp.net?
I have Topic which contain many playlists.
My code:
public class Topic
{
public int Id { get; set; }
public String Name { get; set; }
public String Image { get; set; }
---> public virtual List<Playlist> Playlist { get; set; }
}
and
public class Playlist
{
public int Id { get; set; }
public String Title { get; set; }
public int TopicId { get; set; }
---> public virtual Topic Topic { get; set; }
}
My controller function
[Route("data/binding/search")]
public JsonResult Search()
{
var search = Request["term"];
var result= from m in _context.Topics where m.Name.Contains(search) select m;
return Json(result, JsonRequestBehavior.AllowGet);
}
When I debug my code I will see an infinite data because Topics will call playlist then playlist will call Topics , again the last called Topic will recall playlist and etc ... !
In general when I just use this relation to print my data in view I got no error and ASP.NET MVC 5 handle the problem .
The problem happens when I tried to print the data as Json I got
Is there any way to prevent an infinite data loop in JSON? I only need the first time of data without call of reference again and again
You are getting the error because your entity classes has circular property references.
To resolve the issue, you should do a projection in your LINQ query to get only the data needed (Topic entity data).
Here is how you project it to an anonymous object with Id, Name and Image properties.
public JsonResult Search(string term)
{
var result = _context.Topics
.Where(a => a.Name.Contains(term))
.Select(x => new
{
Id = x.Id,
Name = x.Name,
Image = x.Image
});
return Json(result, JsonRequestBehavior.AllowGet);
}
If you have a view model to represent the Topic entity data, you can use that in the projection part instead of the anonymous object
public class TopicVm
{
public int Id { set;get;}
public string Name { set;get;}
public string Image { set;get;}
}
public JsonResult Search(string term)
{
var result = _context.Topics
.Where(a => a.Name.Contains(term))
.Select(x => new TopicVm
{
Id = x.Id,
Name = x.Name,
Image = x.Image
});
return Json(result, JsonRequestBehavior.AllowGet);
}
If you want to include the Playlist property data as well, you can do that in your projection part.
public JsonResult Search(string term)
{
var result = _context.Topics
.Where(a => a.Name.Contains(term))
.Select(x => new
{
Id = x.Id,
Name = x.Name,
Image = x.Image,
Playlist = x.Playlist
.Select(p=>new
{
Id = p.Id,
Title = p.Title
})
});
return Json(result, JsonRequestBehavior.AllowGet);
}
I am in a big trouble. I read 4 stackoverflow question and one blogpost. I have tried 5 different approach to view the selected items in a multiple selectlist.
I have no success.
The multiple selectlist is generated, but it does not select the items. I have no more idea.
Model:
public class EditableModel
{
public IList<Company> SelectedCompanies { get; set; }
public IList<SelectListItem> SelectListCompanies { get; set; }
}
Controller:
public ActionResult Edit(int id)
{
var service = _serviceDAL.GetEditableModel(id);
if (service!= null)
{
service.SelectListCompanies = GetSelectListCompanies(service.SelectedCompanies);
return View(service);
}
}
private IList<SelectListItem> GetSelectListCompanies(IList<Company> selectedCompanies)
{
List<SelectListItem> items = new List<SelectListItem>();
foreach (Companycompany in _companyService.GetCompanies())
{
items.Add(new SelectListItem
{
Value = company.CompanyId.ToString(),
Text = company.Name,
Selected = selectedCompanies.Any(x => x.CompanyId == company.CompanyId)
});
}
return items;
}
View
#Html.ListBox("SelectedCompanies", Model.SelectListCompanies, Model.SelectedCompanies.Select(x => x.CompanyId.ToString()) )
And nothing. The items in the select list is not selected...
I have tried this Multiselect, the same result, or this one as the current solution.
You cannot bind a <select multiple> to a collection of complex objects. It binds to, and posts back an array of simple values (the values of the selected options).
Your SelectedCompanies property needs to be IEnumerable<int> (assuming the CompanyId of Company is also int). Note also the Selected property of SelectListItem is ignored when binding to a property.
Your also using the same collection for the selected Companies and the list of all Companies which makes no sense. Your SelectListCompanies should be generated from your table of Company.
Model
public class MyViewModel
{
public IEnumerable<int> SelectedCompanies { get; set; }
public IEnumerable<SelectListItem> SelectListCompanies { get; set; }
}
Base on your current code for EditableModel, your code should be
public ActionResult Edit(int id)
{
var service = _serviceDAL.GetEditableModel(id);
....
MyViewModel model = new MyViewModel
{
SelectedCompanies = service.SelectedCompanies.Select(x => x.CompanyId),
SelectListCompanies = GetSelectListCompanies()
};
return View(model);
private IEnumerable<SelectListItem> GetSelectListCompanies()
{
var all companies = ... // call method to get all Companies
return companies.Select(x => new SelectListItem
{
Value = x.CompanyId.ToString(),
Text = x.Name
});
}
However, it look like you should be modifying your EditableModel and the GetEditableModel() code to return the correct data in the first place.
In my controller I have a function to get the roles that belong to a user.
This function is using .GetRolesAsync() and is returning an IList.
In the browser the user can submit a name, and see the roles for a user.
This however returns my list in a blank page. example
Controller :
[HttpPost]
public async Task<IList<string>> GetRoles(UserRoleViewModel model)
{
ApplicationUser user = await _userManager.FindByEmailAsync(model.Email);
if(user != null)
{
model.GetRoles = await _userManager.GetRolesAsync(user);
}
return model.GetRoles;
}
How can I return this list to my ViewModel without opening a blank page so I can call this from my view ?
ViewModel :
public class UserRoleViewModel
{
public List<SelectListItem> Roles { get; set; }
public IList<string> GetRoles { get; set; }
public string Role { get; set;}
public string Email { get; set; }
public string CurrentPassword { get; set; }
public string NewPassword { get; set; }
}
As per my knowledge, you are getting the blank page because , when the below method get executes,
Existing code :
[HttpPost]
public async Task<IList<string>> GetRoles(UserRoleViewModel model)
{
ApplicationUser user = await _userManager.FindByEmailAsync(model.Email);
if(user != null)
{
model.GetRoles = await _userManager.GetRolesAsync(user);
}
return model.GetRoles;
}
It return just result of list and doesn't return any actionresult to retain in the same view
Solution :
Make the returntype of the method like below
Replaced code :
[HttpPost]
public async Task<ActionResult> GetRoles(UserRoleViewModel model)
{
ApplicationUser user = await _userManager.FindByEmailAsync(model.Email);
if(user != null)
{
model.GetRoles = await _userManager.GetRolesAsync(user);
}
return view("viewname")
//Note: here viewname can be the same view ,where this post method was
// called if you dont want to create new view
}
And specify the view name of which you called this post method, if you dont want to create a new view.
So that it wont give a blank page for the user , when it is called.
Hope the above information was useful , kindly let me know your thoughts or feedbacks
Thanks
Karthik
I managed to populate DropDownList with value from a Database in ASP.NET MVC 5. My goal is to assing one of the dropDownList's value to a specific model, and send it back to the Database. So, if i leave the default value in the dropdownlist, the data in SQL server is null, which is Okay, but if I choose an option, I get an error :
Exception thrown: 'System.InvalidOperationException' in System.Web.Mvc.dll ("There is no ViewData item of type 'IEnumerable' that has the key 'Status'."). I tried everything so far and i am opened for suggestions. Thank you !!!
In Controller :
ViewBag.Status = new SelectList(db.Status, "Id", "Name");
in View
#Html.DropDownList("Status","Select status...")
In Controller so far..
public ActionResult Index()
{
return View();
}
[HttpGet]
public ActionResult Apply(ViewModelVM vm,int x=0)
{
myDb db = new myDb();
ViewBag.SocialStatus = new SelectList(db.SocialStatuses, "Id", "StatusDescription");
return View();
}
[HttpPost]
public ActionResult Apply(ViewModelVM vm)
{
if (ModelState.IsValid)
{
using (myDb db = new myDb())
{
var personalinfo = new PersonalInformation()
{
FirstName = vm.PersonalInformation.FirstName,
LastName = vm.PersonalInformation.LastName,
Birthdate = vm.PersonalInformation.Birthdate,
SocialStatus = vm.SocialStatus
};
ViewBag.SocialStatus = new SelectList(db.SocialStatuses, "Id", "StatusDescription");
db.PersonalInformations.Add(personalinfo);
db.SaveChanges();
}
return View("Success");
}
return View();
}
The model:
public partial class Status
{
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
public SocialStatus()
{
PersonalInformations = new HashSet<PersonalInformation>();
}
public int Id { get; set; }
[StringLength(20)]
public string StatusDescription { get; set; }
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
public virtual ICollection<PersonalInformation> PersonalInformations { get; set; }
}
}
The ViewModel:
public class ViewModelVM
{
...
public Status SocialStatus { set; get; }
...
}
Firstly your using a view model so include a property in your view model for the SelectList
public IEnumerable<SelectListItem> StatusList { get; set; }
Next remove the parameter for the model from the GET method (and since you don't appear to be using the value of x, that should be removed also)
[HttpGet]
public ActionResult Apply(ViewModelVM vm,int x=0)
{
myDb db = new myDb();
ViewModelVM model = new ViewModelVM()
{
StatusList = new SelectList(db.SocialStatuses, "Id", "StatusDescription");
};
return View(model); // return the model to the view
}
Next, your dropdown is binding to a property named Status but your view model does not contain a property named status (its SocialStatus) and SocialStatus is a complex object and you cannot bind a <select> to a complex object (a <select> only posts back a single value (or array or values in the case of <select multiple>).
In addition, because your view model contains a property which is a complex object with validation attributes on its properties, ModelState will always be invalid because you do not post back a value for StatusDescription. As a result you always return the view in the POST method, and because you have not reassigned ViewBag.Status = ...., it is null, hence the error.
Remove property public Status SocialStatus { set; get; } and include
[Display(Name = "Social Status")]
[Required(ErrorMessage = "Please select a status")]
public int SocialStatus { get; set; }
an then in the view, strongly bind to your model using
#Html.LabelFor(m => m.SocialStatus)
#Html.DropDownListFor(m => m.SocialStatus, Model.StatusList, "-Please select-")
#Html.ValidationMessageFor(m => m.SocialStatus)
Then, in the POST method, if ModelState is invalid, populate the select list again before returning the view
if(!ModelState.IsValid)
{
model.StatusList = new SelectList(db.SocialStatuses, "Id", "StatusDescription");
return View(model);
}
// save and redirect
Finally, review What is ViewModel in MVC?.
So what I'm doing might seem simple, but I don't know exactly how to do it.
I have already registered and logged in with an account (I'm using the default membership system used in ASP.NET MVC 4) and so I want to do add my UserId to some data I'm inserting to the database.
This is the model of the data I'm inserting:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace Reroute.Models
{
public class Request
{
public int RequestId { get; set; }
// I want to add UserId based on my current session
public int UserId { get; set; }
public string OrderNumber { get; set; }
public string TrackingNumber { get; set; }
public string CurrentAddress { get; set; }
public string NewAddress { get; set; }
public string Comment { get; set; }
}
}
And the ActionResult (here's where I supposed I have to make the changes):
[HttpPost]
public ActionResult Create(Request collection)
{
try
{
_db.Requests.Add(collection);
_db.SaveChanges();
//return RedirectToAction("Index");
return Content("Done! Added to DB");
}
catch
{
return View();
}
}
Thanks
use this it gets u the userid ...
Membership.GetUser().ProviderUserKey
You can save the UserId of the authenticated user in Session after logging in:
Session["UserId"] = userId;
or since you are using FormsAuthentication you can either use the UserData property as shown here or do a nice-that-will-do-trick:
public SignInUser(string name, string id) {
// store the userid
FormsAuthentication.SetAuthCookie(name + '|' + id, false);
}
then retrieve the Name and UserId like this:
public int CurrentUserId
{
get
{
var context = HttpContext.Current;
if (context == null) return 0;
return context.Request.IsAuthenticated
? Convert.ToInt32(context.User.Identity.Name.Split('|')[1])
: 0;
}
}
public string CurrentUserName
{
get
{
var context = HttpContext.Current;
if (context == null) return string.Empty;
return context.Request.IsAuthenticated
? context.User.Identity.Name.Split('|')[0]
: string.Empty;
}
}
You can have those method and properties in a class so you have them in one place, I actually do it that way. Now, you can call it in your controller like so:
[HttpPost]
public ActionResult Create(Request collection)
{
try
{
collection.UserId = _authProvider.CurrentUserId;
// if you want to use session, I prefer the FormsAuthentication approach
// you need to do additional check that the Session has not expired (not null)
collection.UserId = Session["UserId"];
_db.Requests.Add(collection);
_db.SaveChanges();
//return RedirectToAction("Index");
return Content("Done! Added to DB");
}
catch
{
return View();
}
}
_authProvider is an instance of the class that has the code I gave above.
This should work.
var loggedInUserName=Thread.CurrentPrincipal.Identity.Name;
var user=Membership.GetUser(loggedInUserName);
var key = user.ProviderUserKey;
T
Assuming your Create also has a GET which is loaded up and used as the model for Create.cshtml, you would just need to set it explicitly in that ActionResult
public ActionResult Create()
{
Result model = new Result();
model.UserId = myUserId;
}
Then in your Create.cshtml you could have a hidden field for it:
#Html.HiddenFor(m => m.UserId)
I would still check in the POST to make sure the user doing the saving is allowed to be saving and hasn't spoofed your hidden field value to somebody completely different.