I want to get the values of dynamically added Textbox on submit button in MVC 3.
I am storing the values in hidden field and getting using FromCollection. Is there any better approach?
If you name your values something like
MyValues[x] where x is a zero based, continuously increasing integer, you can receive the string values as a list of strings named MyValues.
This trick also works for properties if the main model object, if needed.
You should check some articles about how to bind to collections In ASP mvc, they could give you some ideas.
For example http://haacked.com/archive/2008/10/23/model-binding-to-a-list.aspx
You could do something like this (written very quickly outside of editor, so may have typos/issues):
Make a view model:
public class DynamicTextBoxViewModel
{
public IList<string> DynamicTextBox { get; set; }
public int OtherStuffInViewModel { get; set; }
}
Then in your Get Action:
var model = new YourViewModel
{
DynamicTextBoxList =
new List<DynamicTextBox>
{
new DynamicTextBox
{
TextBoxText = string.Empty,
}
},
OtherStuffInViewModel = xxx,
};
return View(model)
Then in your Post Action:
You would bind everything where you wanted it.
The idea is to move all the data into a ViewModel and pass that around so you gain the benefits of the ViewModel instead of passing around FormCollection - which is sloppier and more error prone.
Related
Currently using the Kendo UI AutoCompleteFor() and ComboBoxFor() helper.
Noticing that they generate/render a bunch of <li>s.
How does one add additional custom data-* attributes to those <li>s?
Here's the current scenario:
The user starts typing stuff in the AutoCompleteFor
An ajax call is triggered to fetch some data related to what the
user has typed.
The obtained results are transformed into an
IEnumerable<SelectListItem>.
The result is then sent to Json. Json(result, JsonRequestBehavior.AllowGet)
My goal is to add one or more additional data-* attribute to each of these <li> generate lines so that I can fetch these data-* in the onChange() event.
How does one achieve this?
In addition, I'm aware that I could create my own .Template() and possibly achieve my task but I was curious if anyone knows of a different way to do this then having to create my own template.
Sincerely
Ok I've found a solution; I'll share it here in case anyone is interested.
Instead of transforming my obtained results into an IEnumerable<SelectListItem>, I simply transform this into an IEnumerable<CustomDTO>.
The CustomDTO class looks like this:
public class CustomDTO
{
public int Value { get; set; }
public string Text { get; set; }
public int Age { get; set; }
//Add whatever more properties you think you’ll need.
}
In my controller, I then do the following:
var result = _myService.GetData().ToList();
return Json(result, JsonRequestBehavior.AllowGet);
Where GetData() returns an IEnumerable<CustomDTO>.
Inside my View, I have an AutoCompleteFor() control to which I bind a client side
.Events(x => x.Select("onSelect") event handler.
The handler is defined like so:
function onSelect(e)
{
if (e.item == null) return;
var dataItem = this.dataItem(e.item.index());
var valueAttribute = dataItem.Value;
var textAttribute = dataItem.Text;
var ageAttribute = dataItem.Age; //This is how I get my additional value
//...code...
}
So that's it.
I am using MVVM and displaying some items on a DataGrid. My model is RecordingInfo and looks like:
public class RecordingInfo : IDataErrorInfo
{
public RecordingInfo(string fullDirectoryName, string recordingName, int recordingNumber)
{
FullDirectoryName = fullDirectoryName;
RecordingName = recordingName;
RecordingNumber = recordingNumber;
}
public string FullDirectoryName { get; internal set; }
public string RecordingName { get; set; }
public int RecordingNumber { get; internal set; }
public string Error
{
get { throw new NotImplementedException(); }
}
public string this[string propertyName]
{
get {
if (propertyName == "RecordingName")
{
if (this.RecordingName.Length < 2)
return "Recording Name must be at least two characters";
}
return null;
}
}
}
I end up with a collection of these RecordingInfo programmatically. The user is not allowed to do much with these but he/she can change the RecordingName subject to the name being 2 characters or more AND that the RecordingName must be unique. I.e. no changing it to match another RecordingName. I have taken care of the first requirement. It's the second one that is giving me grief.
For my ViewModel, I have
public class RecordingListViewModel : ViewModelBase//, IDataErrorInfo
{
private ObservableCollection<RecordingInfo> _recordings = null;
public RecordingListViewModel()
{
}
public ObservableCollection<RecordingInfo> Recordings
{
get
{
return _recordings;
}
}
// more stuff left off for brevity
In my view I bind the collection to a DataGrid and have:
<DataGrid ItemsSource="{Binding Path=Recordings}" AutoGenerateColumns="False" >
<DataGrid.Columns>
<DataGridTextColumn Header="Recording" IsReadOnly="False" EditingElementStyle="{StaticResource CellEditStyle}" ElementStyle="{StaticResource CellNonEditStyle}" Binding="{Binding RecordingName, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" >
</DataGridTextColumn>
...
</DataGrid.Columns>
My way of checking for 2 or more characters works great. But this doesn't work for checking that the user is not trying to give a recording an existing name. Presumably, I need to somehow handle this at the ViewModel layer since the ViewModel knows about all Recordings. I tried playing with having my ViewModel derive from IDataErrorInfo but the property indexer never gets called, which makes sense as it's the Observable collection and therefore the individual RecordingInfos that are bound. I also thought about doing something with a "Lost Focus" event, but DataGridTextColumn doesn't seem to have that. I would think this is a somewhat common problem: validation must take into account relationships between the items of the collection.
By the way, I'm not wedded to the IDataErrorInfo and I am not opposed to other changes in architecture. Please let me know if I can provide more details. I have tried to provide a minimal amount of code. Clearly, this is part of a much bigger project. Any advice is appreciated.
Thanks,
Dave
I would do the following
1) Make RecordingInfo implement INotifyPropertyChanged
2) Use a BindingList<> instead of ObservableCollection<>
In your viewmodel, subscribe to the BindingList.ListChanged Event. This event will fire when items are added and removed, but also when the top level properties on RecordingInfo changes. In the case of a property being changed, the ListChangedEventArgs.PropertyDescriptor property will contain the name of the property, if you want to run validation for just that property (be careful though, this can be null when the item as added/removed). You'll need to use the ListChangedType property to determine the reason of the event (E.x.: Reset means everything changed, ItemAdded means the item was added, but the ItemChanged means a property changed as occurred on an existing item.
You can have the parent ViewModel (that contains and creates your RecordingInfos) pass a name validation Func in their constructors for them to call when validating their name changes.
I am using the example at The Complete Guide To Validation In ASP.NET MVC 3 to create a RequiredIf validation attribute (it's about 1/3 down the page under the heading of "A more complex custom validator"). It all works fine with the exception of one scenario, and that is if I have the need to validate against a complex type. For example, I have the following model:
public class MemberDetailModel
{
public int MemberId { get; set; }
// Other model properties here
public MemberAddressModel HomeAddress { get; set; }
public MemberAddressModel WorkAddress { get; set; }
}
public class MemberAddressModel
{
public bool DontUse { get; set; }
// Other model properties here
[RequiredIf("DontUse", Comparison.IsEqualTo, false)]
public string StreetAddress1 { get; set; }
}
The problem is that when the attribute validation for the StreetAddress property is rendered, it get's decorated with the attribute of data-val-requiredif-other="DontUse". Unfortunately, since the address is a sub-type of the main model, it needs to be decorated with a name of HomeAddress_DontUse and not just DontUse.
Strangely enough, the validation works fine for server-side validation, but client-side unobtrusive validation fails with an JS error because JS can't find the object with a name of just "DontUse".
Therefore, I need to find a way to change the ModelClientValidationRequiredIfRule method to know that the property it is validating is a sub-type of a parent type, and if so, prepend the ParentType_ to the "otherProperty" field (e.g. otherProperty becomes HomeAddress_DontUse.
I have tried passing in typeof(MemberAddressModel) as a parameter of the attribute, but even when debugging the attribute creation, I can't seem to find any reference to the parent type of HomeAddress or WorkAddress from that type.
Based on the suggestion from The Flower Guy, I was able to come up with the following which seems to work. I simply modified the following in the customValidation.js file:
jQuery.validator.addMethod("requiredif", function (value, element, params) {
if ($(element).val() != '') return true;
var prefix = getModelPrefix(element.name); // NEW LINE
var $other = $('#' + prefix + params.other); // MODIFIED LINE
var otherVal = ($other.attr('type').toUpperCase() == "CHECKBOX") ? ($other.attr("checked") ? "true" : "false") : $other.val();
return params.comp == 'isequalto' ? (otherVal != params.value) : (otherVal == params.value);
});
I also added the following method to that file (within the JQuery block so as to be only privately accessible):
function getModelPrefix(fieldName) {
return fieldName.substr(0, fieldName.lastIndexOf(".") + 1).replace(".","_");
}
Cannot do it exactly right now, but the problem is in the client javascript function:
jQuery.validator.addMethod("requiredif" ...
The js is not sophisticated enough to cope with complex view models where there may be a model prefix. If you take a look at Microsoft's jquery.validate.unobstrusive.js (in the Scripts folder over every MVC3 application), you will find some useful methods including getModelPrefix and appendModelPrefix. You can take a similar approach and change the requiredIf validation method - take a look at the equalto method in jquery.validate.unobstrusive.js for a helping hand.
I have a question.
My question actually extends from this one:
Shortly - what I want to get: 3 models, and 1 super model for this specific view. This super model fills(properly) IENumerable, IENumerable, IENumerable, to use them in View part. (as far as I understand it, at least...)
In this other topic Dan Revell proposed verry nice and elegant solution, but this solution does not fetch data from DB itself...
Question:
What must be done to get data in this model from DB, not from "new" instance constructors?
While using this approach tried to fetch data from DBContext. And got some problems in it ) I can't understand when (or how) to create my DBContext... Or how to access one that is created by application...
Tried to create it forcefully in Controller, like
using (var Db = new thetaskermvc.Models.TaskerDBContext())
{
var themodel = new thetaskermvc.Models.TotalView();
//Jobbers
themodel.Jobberz = new Dictionary<int, thetaskermvc.Models.Jobbers>();
var jobbers = from Jobbers in Db.Jobbers.OrderBy(g => g.jobb_name) select Jobbers;
foreach (Models.Jobbers ad in jobbers)
{
themodel.Jobberz.Add(ad.jobb_id,
new Models.Jobbers(ad.jobb_id, ad.jobb_name, ad.jobb_from, ad.jobb_carma, ad.jobb_status, ad.jobb_balance, ad.jobb_time));
}
if (themodel.Jobberz.Count == 0)
{
themodel.Jobberz.Add(-1, new Models.Jobbers(0, "NOTHING FOUND",DateTime.Now,0,"",0,0));
}
}
But as created that way Context stops it's existence (?) after passing data away from controller - I can't use it any other way but to get all data inside this controller, and fill data in model by direct add into collections in it (while use of IENumerable would fetch data on-demand, as far as I get it).
So.. If it ain't hard please enlighten me about - is it Ok to use such approach, or there is some other "common" way? Becaus beside it's clumsiness - this approach works...
PS I'm quite new to Asp, yet...
I have one view model per view with data from multiple tables (if required). On my view I have data that needs to be loaded from 2 different database tables. In my grant application controller I have the following:
private readonly IBankService bankService;
private readonly IAccountTypeService accountTypeService;
public GrantApplicationController(IBankService bankService, IAccountTypeService accountTypeService)
{
// Check incoming parameters for null values
this.bankService = bankService;
this.accountTypeService = accountTypeService;
}
In my Create action method I populate my banks and account types (to be used in drop downs) like this (different tables):
public ActionResult Create()
{
GrantApplicationCreateViewModel viewModel = new GrantApplicationCreateViewModel
{
Banks = bankService.FindAll(),
AccountTypes = accountTypeService.FindAll()
}
// Do what ever else you need to get done
return View(viewModel);
}
My partial view model would like this:
public class GrantApplicationCreateViewModel
{
public int BankId { get; set; }
public IEnumerable<Bank> Banks { get; set; }
public int AccountTypeId { get; set; }
public IEnumerable<AccountType> AccountTypes { get; set; }
// Other properties
}
In my repository class I would use the database context like this (I use Entity Framework code first):
public class BankRepository : IBankRepository
{
HefContext db = new HefContext
public IEnumerable<Bank> FindAll()
{
return db.Banks.OrderBy(x => x.Name);
}
}
In my database context class:
public class HefContext : DbContext
{
public DbSet<Bank> Banks { get; set; }
public DbSet<AccountType> AccountTypes { get; set; }
}
Doing it this way you can have one view model that has data from multiple sources. I hope this answers your question? If you need more explanation please let me know :)
You may want to have a look at this post, it explains (with a sample project) how an ideal MVC application architecture should be.
In your code sample above, your shouldn't have any references to DbContexts in a controller. Controller's job is to control the flow of requests not to connect to the DB and perform Model population.
Ok, this was supposed to be a question asking for help getting my form to work properly. In the process of creating an example to post, I figured out what the fix is.
So now it's a become a question about why it works one way and not the other. I really cannot understand the behaviour. Have I found a bug in MVC? Or is there something I don't understand about html requests which makes this behaviour correct?
The example invloves setting the selected value in a dropdown through an enum property in a view model which is bound from the querystring (it's probaly clearer what I'm talking about if you just read the code):
Controller/Model
public class HomeController : Controller
{
public ActionResult Index(TestModel model)
{
return View(model);
}
}
public class TestModel
{
public SelectList EnumOptions { get; set; }
public TestEnum EnumValue { get; set; }
public TestModel()
{
var options = from Enum e in Enum.GetValues(typeof(TestEnum))
select new { Value = e, Name = e.ToString() };
EnumOptions = new SelectList(options, "Value", "Name", TestEnum.NotSet);
}
}
public enum TestEnum
{
NotSet = 0,
Dog = 1,
Cat = 2
}
View
#Html.DropDownListFor(m => m.EnumValue, Model.EnumOptions)
Dog numeric
Dog string
It's all pretty simple.
The question is, why doesn't the second "Dog" link work properly? Note it submits the enumValue as a numeric property, instead of as a "string" property.
But the model binder has no problem with this. The model supplied to the View is exactly the same in either case. So how does the dropdown selected value get rendered correctly in one case but not the other?
DropDownListFor looks into the modelstatedictionary for getting the current value of the field/property.
The ValueProviderResult for the second link has a value from 1.
The modelbinder knows that the requested type is a TestEnum. A 1 can be converted to Dog.
The dropwdownlist converts the value of the ValueProviderResult into a string. A 1 converts to "1" as a string. There is no entry in the selectlist with a value of "1".
Therefor the dropdownlist has a wrong current value.