I'm experiencing very odd behavior in the way an ASP.NET MVC3 view model is emitted -- for one field, ModelMetadata is not propagated. I'm using the templated helpers after Brad Wilson, though updated for Razor. Here's my view model:
public class FamilyBaseViewModel : ViewModelBase
{
[Display(Order = 10)]
public string FamilyName { get; set; }
[Display(Order = 30)]
[StringLength(50, ErrorMessage = "Street name can only be 50 characters long.")]
public string Street { get; set; }
}
public class FamilyPrivateViewModel : FamilyBaseViewModel
{
[Display(Name = "Date Started", Order = 20)]
[DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:d}")]
[DataType(DataType.Date)]
public DateTime? DateStarted { get; set; }
}
The object.cshtml template runs through the properties and uses Html.Display to show them:
// object.cshtml
<ol>
#foreach (var prop in
ViewData.ModelMetadata.Properties.Where(pm => pm.ShowForDisplay
&& !ViewData.TemplateInfo.Visited(pm)
&& pm.ModelType != typeof(System.Data.EntityState)))
{
<li>
#Html.Display(prop.PropertyName)
</li>
}
</ol>
In the above scenario, all three fields have the right descriptors in the object.cshtml call (prop.DisplayName, prop.TemplateHint), but when the first property -- FamilyName -- is passed to String.cshtml, the ViewData.ModelMetadata is not populated at all. As a result, the template can't display a label (except "String"), nor assign the ID of the control, etc.
Street and DateStarted are emitted normally, with the ID and all. So I'm completely at a loss as to why the one property would fail to set the ViewData properties -- nor do I know how to step through past the Html.Display call to see what might be happening.
Any ideas for a next place to look?
So the problem was in the controller action, which for unrelated reasons used "FamilyName" for a ViewData value:
ViewBag.FamilyName = familyName;
And this caused all heck to break loose in the mapping of model fields with the same name -- that is, ModelMetadata will not propagate. So, the lesson is: don't give ViewData dictionary items keys with the same name as a field in your view model.
Related
I am building a simple ASP.NET MVC 3 site, using Entity Framework to build the model based on some tables in an already existing Oracle database (in other words, I used the 'database first' methodology to have my model built). I now have a simple blog type site, which I am quite familiar with as I have been learning MVC in a number of languages.
I want to change some of the auto-generated views. One piece I would like to change in particular is that I have a field in one of my tables called 'Visible'. This is simply a numeric value (0 or 1) indicating whether or not a display application should use the row as display data. Currently, I have the simple text field that is auto-generated:
<div class="editor-field">
#Html.EditorFor(model => model.VISIBLE)
#Html.ValidationMessageFor(model => model.VISIBLE)
</div>
What I would like to do is replace this with a drop down box with string values like True and False. The application should display any entry with a 0 as false and vice versa. If a user wants to flip the toggle, the drop down should allow them to do that and understand to make the numeric update when clicking submit. How can this be done?
I have seen countless examples where the drop-down was going to be filled with more then just two values, and in those cases I understand that you can add logic to your controller that pulls all the distinct values, puts them in a list, then adds the list to the ViewBag. However, in my case with only two possible numeric values, it seems like there should be a simpler, more accepted way to do it.
Any help is greatly appreciated.
UPDATE
Following Quinton's answer, I am trying to place said code in my model. Here is my current model:
namespace CurrentActivityBlog
{
using System;
using System.Collections.Generic;
using System.Web.UI.WebControls;
public partial class TBLCURRENTACTIVITY
{
public string TITLE { get; set; }
public string DESCRIPTION { get; set; }
public System.DateTime DATETIME { get; set; }
public short VISIBLE { get; set; }
public decimal ID { get; set; }
public IEnumerable<SelectedListItem> PossibleValues { get; set; }
public TBLCURRENTACTIVITY() {
PossibleValues = new[] { new SelectListItem { Value = "0", Text = "Hidden" },
new SelectListItem { Value = "1", Text = "Visible" } };
}
}
}
I am unable to build this solution, but Visual Studio 2010 is telling me that
"the type or namespace name 'SelectedListItem' could not be found (are you missing a using directive or an assembly reference?)"
As you can see, I have
using System.Web.UI.controls
and have added the reference to System.Web. Is there anything I am forgetting, or anything I should know about (such as models generated using EF behaving differently then one might expect, etc.)?
Thanks again.
The one line solution to it would be:
#Html.DropDownList(Model.VISIBLE.ToString(), new [] {new SelectListItem { Value = "0", Text = "Hidden"}, new SelectListItem { Value = "1", Text = "Visible"}})
but you probably don't want domain logic in your view. So add the possible items to your Model (or from the controller):
public class MyModel {
public int VISIBLE { get; set; }
public IEnumerable<SelectListItem> PossibleValues { get; set; }
public MyModel() {
PossibleValues = new[] { new SelectListItem { Value = "0", Text = "Hidden" }, new SelectListItem { Value = "1", Text = "Visible" } };
}
}
and then your razor code:
#Html.DropDownList(Model.VISIBLE.ToString(), Model.PossibleValues)
Obviously "Hidden" and "Visible" descriptions can be replaced with "False" and "True" or whatever.
You could also create and Editor and Display Template for that specific field. Checkout ScottGu's blog post here, search for "UI Helper Templating Support" and you'll see how to create a editor template and how to render a specific template by name.
EDIT:
If your model is not part of your MVC project, then referencing any classes that are in the MVC assemblies would require a explicit add reference. You can avoid this though by initializing any MVC assembly types in your model from your controller, like such:
public class MyModel {
public int VISIBLE { get; set; }
public IEnumerable<SelectListItem> PossibleValues { get; set; }
}
controller action method:
public ActionResult Edit(int Id) {
...
myModelInstance. PossibleValues = new[] { new SelectListItem { Value = "0", Text = "Hidden" }, new SelectListItem { Value = "1", Text = "Visible" } };
...
Return View(myModel);
}
I'm working on the first MVC3 project at our company, and I've hit a block. No one can seem to figure out what's going on.
I have a complex Model that I'm using on the page:
public class SpaceModels : List<SpaceModel> {
public bool HideValidation { get; set; }
[Required(ErrorMessage=Utilities.EffectiveDate + Utilities.NotBlank)]
public DateTime EffectiveDate { get; set; }
public bool DisplayEffectiveDate { get; set; }
}
In the Controller, I create a SpaceModels object with blank SpaceModels for when Spaces get combined (this would be the destination Space).
// Need a list of the models for the View.
SpaceModels models = new SpaceModels();
models.EffectiveDate = DateTime.Now.Date;
models.DisplayEffectiveDate = true;
models.Add(new SpaceModel { StoreID = storeID, SiteID = siteID, IsActive = true });
return View("CombineSpaces", models);
Then in the View, I am using that SpaceModels object as the Model, and in the form making a TextBox for the Effective Date:
#model Data.SpaceModels
#using (Html.BeginForm("CombineSpaces", "Space")) {
<div class="EditLine">
<span class="EditLabel LongText">
New Space Open Date
</span>
#Html.TextBoxFor(m => m.EffectiveDate, new {
size = "20",
#class = "datecontrol",
// Make this as a nullable DateTime for Display purposes so we don't start the Calendar at 1/1/0000.
#Value = Utilities.ToStringOrDefault(Model.EffectiveDate == DateTime.MinValue ? null : (DateTime?)Model.EffectiveDate, "MM/dd/yyyy", string.Empty)
})
#Html.ValidationMessageFor(m => m.EffectiveDate)
</div>
<hr />
Html.RenderPartial("_SpaceEntry", Model);
}
The Partial View that gets rendered iterates through all SpaceModels, and creates a containing the Edit fields for the individual SpaceModel objects. (I'm using the List to use the same Views for when the Spaces get Subdivided as well.)
Then on the HttpPost, the EffectiveDate is still back at it's DateTime.MinValue default:
[HttpPost]
public ActionResult CombineSpaces(SpaceModels model, long siteID, long storeID, DateTime? effectiveDate) {
// processing code
}
I added that DateTime? effectiveDate parameter to prove that the value when it gets changed does in fact come back. I even tried moving the rendering of the TextBox into the _SpaceEntry Partial View, but nothing worked there either.
I did also try using the #Html.EditorFor(m => m.EffectiveDate) in place of the #Html.TextBoxFor(), but that still returned DateTime.MinValue. (My boss doesn't like giving up the control of rendering using the #Html.EditorForModel by the way.)
There has to be something simple that I'm missing. Please let me know if you need anything else.
Looking at the source code for DefaultModelBinder, specifically BindComplexModel(), if it detects a collection type it will bind the individual elements but will not attempt to bind properties of the list object itself.
What model binding does is attempt to match the names of things or elements in the view to properties in your model or parameters in your action method. You do not have to pass all of those parameters, all you have to do is add them to your view model, then call TryUpdateModel in your action method. I am not sure what you are trying to do with SpaceModel or List but I do not see the need to inherit from the List. Im sure you have a good reason for doing it. Here is how I would do it.
The view model
public class SpacesViewModel
{
public DateTime? EffectiveDate { get; set; }
public bool DisplayEffectiveDate { get; set; }
public List<SpaceModel> SpaceModels { get; set; }
}
The GET action method
[ActionName("_SpaceEntry")]
public PartialViewResult SpaceEntry()
{
var spaceModels = new List<SpaceModel>();
spaceModels.Add(
new SpaceModel { StoreID = storeID, SiteID = siteID, IsActive = true });
var spacesVm = new SpacesViewModel
{
EffectiveDate = DateTime.Now,
DisplayEffectiveDate = true,
SpaceModels = spaceModels
};
return PartialView("_SpaceEntry", spacesVm);
}
The POST action method
[HttpPost]
public ActionResult CombineSpaces()
{
var spacesVm = new SpacesViewModel();
// this forces model binding and calls ModelState.IsValid
// and returns true if the model is Valid
if (TryUpdateModel(spacesVm))
{
// process your data here
}
return RedirectToAction("Index", "Home");
}
And the view
<label>Effective date: </label>
#Html.TextBox("EffectiveDate", Model.EffectiveDate.HasValue ?
Model.EffectiveDate.Value.ToString("MM/dd/yyyy") : string.empty,
new { #class = "datecontrol" })
Sometimes you need to explicitly bind form data using hidden fields such as
#Html.HiddenField("EffectiveDate", Model.EfectiveDate.)
In order to bind the properties of the SpaceModel object you can add individual properties such as SiteID to the view model or add a SpaceModel property for a single SpaceModel. If you want to successfully bind a complex model, add it as a Dictionary populated with key-value pairs rather than a List. You should then add the dictionary to the view model. You can even add a dictionary of dictionaries for hierarchical data.
I hope this helps :)
I have two classes as follows
public class ODCTE_Major
{
public int ODCTE_MajorId { get; set; }
public string OfficialMajorName { get; set; }
public string MajorCode { get; set; }
... More unrelated code ....
}
AND
public class CareerMajor
{
...lots of unrealted code to this question left out
public int ODCTE_MajorId { get; set; }
public virtual ODCTE_Major ODCTE_Major { get; set; }
}
I added a controller with CRUD methods and in the create.cshtml there is this line
<div class="editor-field">
#Html.DropDownList("ODCTE_MajorId", String.Empty)
#Html.ValidationMessageFor(model => model.ODCTE_MajorId)
</div>
The select list populates it with the OfficialMajorName from ODCTE_Major. I need the select list to populate with the MajorCode or a value that looks like MajorCode - OfficialMajorName.
Could someone provide assistance for how this is done, please?
Thanks.
Add this to ODCTE_Major:
public string MajorDisplayName
{
get { return string.Format("{0} - {1}", MajorCode, OfficialMajorName); }
}
This is just a read only property used to create the display text in the format you want the menu to use.
Then in CareerMajor, add:
public IEnumerable<ODCTE_Major> Majors{ set; get; } // Thank you Shyju!
This will give you a place in your view model to pass the list of Majors you want in your menu to the view.
Then in your action method when you're creating a CareerMajor view model to send to the view, populate the new IEnumberable with the ODCTE_Major entities you'd like displayed in your menu.
On the view page:
#Html.DropDownListFor(m => m.ODCTE_MajorId, new SelectList(Model.Majors, "ODCTE_MajorId", "MajorDisplayName", Model.ODCTE_MajorId), "Select One")
This creates a SelectList to populate the drop down with. The SelectList constructor is saying use ODCTE_MajorId as the value for a SelectListItem in the menu, and to use MajorDisplayName as the text to actually display in the menu. It sets the selected value, if there is one, and adds a null item with the text "Select One" to the top of the menu. Feel free to take that final argument out if you don't want the null text.
Have your ViewModel hold a Collection property to represent all available Majors (for poulating the Dropdown)
public class CareerMajor
{
//other proiperties
public int ODCTE_MajorId { get; set; }
public IEnumerable<ODCTE_Major> Majors{ set; get; }
}
And in your GET Action, fill it and send it to your strongly typed view
pubilc ACtionResult Create()
{
var viewModel=new CareerMajor();
viewModel.Majors=db.GetllAllMajors(); // getting a list of ODCTE_Major objects
return View(viewModel);
}
and in the View, use the DropDownListFor HTML Helper method.
#model CareerMajor
#Html.BeginForm())
{
#Html.DropDownListFor(m=>m.ODCTE_MajorId,
new SelectList(Model.Majors,"ODCTE_MajorId ","MajorCode"),"select one..")
//other elements
}
In your controller action:
ViewBag.ODCTE_MajorId = new SelectList(availableMajors, "ODCTE_MajorId", "MajorCode");
*second and third parameters are the names of the value and text fields respectively
Then in your view:
#Html.DropDownList("ODCTE_MajorId", String.Empty)
where availableMajors is an IEnumerable that contains the majors you want to list.
How can I return return a collection in a method from a LINQ query that has a one to many relationship?
For instance, I have the following code where I can have many Projects to a TimeTracking object. Will the type that I have defined for the return type (IEnumerable) work? It is set up in my EF model as this specific kind of relationship.
public IEnumerable<TimeTracking> GetTimeTrackings()
{
YeagerTechEntities DbContext = new YeagerTechEntities();
DbContext.Configuration.ProxyCreationEnabled = false;
DbContext.Configuration.LazyLoadingEnabled = false;
var timeTrackings = (from timeTrackingProjects in DbContext.TimeTrackings.Include("TimeTrackings.Projects")
select timeTrackingProjects).Where(p => p.TimeTrackingID > 0);
CloseConnection(DbContext);
return timeTrackings;
}
If so, when I display it in my MVC 3 View, and my View contains an IEnumerable<YeagerTech.YeagerTechWcfService.TimeTracking> model, will the model variable have records in it for the TimeTracking and Project objects? I don't think it will. My TimeTracking object is set up as follows unless I need to inherit the Project class with it (which would then have the Project properties):
public partial class TimeTracking
{
[DataMember]
public int TimeTrackingID { get; set; }
[DataMember]
public short ProjectID { get; set; }
[DataMember]
public byte[] Attachment { get; set; }
[Required]
[DataType(DataType.Date)]
[DataMember]
public System.DateTime StartDate { get; set; }
[Required]
[DataType(DataType.Date)]
[DataMember]
public System.DateTime EndDate { get; set; }
[DataMember]
public string Notes { get; set; }
[DataMember]
public System.DateTime CreatedDate { get; set; }
[DataMember]
public Nullable<System.DateTime> UpdatedDate { get; set; }
[DataMember]
public virtual Project Project { get; set; }
}
I also want my View to display the Project text that is associated with the TimeTracking and not the Project value. How can I do this?Can someone please help?
I got the following msg from invoking a method on my WCF client.
'cannot be serialized if reference tracking is disabled'
After getting the msg, I then modified my DataContracts to include references ([DataContract(IsReference = true)]).
namespace YeagerTechModel
{
[Serializable]
[DataContract(IsReference = true)]
public partial class Customer
{
public Customer()
{
this.Projects = new HashSet<Project>();
}
[DataMember]
public short CustomerID { get; set; }
[Required]
[StringLength(50)]
[DataType(DataType.EmailAddress)]
[DataMember]
public string Email { get; set; }
I am executing the following server side code to successfully get data from my database in a parent/child relationship. The Include method explicity invokes getting the related Project data for the specific Customer. I had to do it this way because you must turn LazyLoading off if you want to get your parent/child data across the wire.
If I look at the WCF messagelog, I can see the actual data coming across in a Customer object and it has the Project object inside of the Customer object.
However, after the call is made and I actually inspect the contents of the "customer" variable, I don't see any refernces to any Project data.
public IEnumerable<Customer> GetCustomers()
{
YeagerTechEntities DbContext = new YeagerTechEntities();
DbContext.Configuration.ProxyCreationEnabled = false;
DbContext.Configuration.LazyLoadingEnabled = false;
IQueryable<Customer> customer = DbContext.Customers.Include("Projects").Where(p => p.CustomerID > 0);
CloseConnection(DbContext);
return customer;
}
The thing I want to do now, is reference the Project data coming back from the call. However, I don't get any Customer object intellisense after typing "customer.". It's all pertains to an IQueryable object.
I'm passing it back into my MVC Controller as the following type:
IEnumerable<YeagerTechWcfService.Customer> customerList = db.GetCustomers();
and into my View as the following model:
IEnumerable<YeagerTech.YeagerTechWcfService.Customer>
Now, the big question is "How can I reference the Project data coming back in my View?
The below is my code for the View, but there is no intellisense for "item.Project". Note that "Email" is a property inside my Customer object.
foreach (var item in Model)
{
<tr>
<td>
#Html.DisplayFor(modelItem => item.Email)
</td>
Looks like your Linq query should be closer to this (NOTE: did not test the query, might need tweaking):
var query = (from tt in DbContext.TimeTrackings.Include("Projects")
where tt.TimeTrackingID > 0
select tt).ToList();
Linq query as you have written is deferred execution, you are closing your connection before retrieving the data, so that would probably cause a runtime error.
.Include() statement should specify the property on the entity (TimeTracking in your case) that need to be loaded, so in this case that would be Project property
Once you have retrieved your enumerable collection of TimeTracking entities you can access the properties of the Project entity associated with a particular TimeTracking entity like so:
foreach(var tracking in GetTimeTrackings())
{
foreach(var project in tracking.Projects)
{
// Assuming your Project entity has a Name property
Response.Write(project.Name);
}
}
I'm not sure what you mean by
I also want my View to display the Project text that is associated
with the TimeTracking and not the Project value.
can you clarify what property from which entity you want to see? What is the Project Entity definition?
In response to your comment about closing connection after retrieving the data:
The statement IQueryable<Customer> customer = DbContext.Customers.Include("Projects").Where(p => p.CustomerID > 0); does not actually execute a query against the database until you start to iterate it (most likely in your view with a foreach statement). If you add a .ToList() at the end of that statement, it will execute it and return a List<Customer> (which is also IEnumerable) which contains all the records that are result of your query.
When you try to type customer. to get intellisense for the Customer entity, you're not seeing it because customer is a list of Customer entities (or rather an IQueryiable of them) so you would need to do something like customer[0]. to access the properties of the first Customer entity in that list (or iterate over it).
I'm not 100% sure how entity references come through in ASP.NET MVC on a model entity but a really simple way you can get this done is create a model class you want to use in your view, say something like this:
public class TimeTrackingModel {
public int TimeTrackingID { get; set; }
public string ProjectName { get; set; }
}
then in your query do this:
var customers = (from tt in DbContext.TimeTrackings.Include("Projects")
where tt.TimeTrackingID > 0
select new TimeTrackingModel { TimeTrackingID = tt.TimeTrackingID, ProjectName = tt.Project.ProjectName }).ToList();
then in your view specify IEnumberable<TimeTrackingModel> as the model and then access the properties like this:
foreach (var item in Model)
{
<tr>
<td>
#Html.DisplayFor(modelItem => item.ProjectName)
</td>
Actually, after further review, I can now see the Project collection in my Customer collection all the way back up to my client after adding a QucikWatch on the object.
The correct answer is the last part of my post where the LazyLoadingEnabled = false appears.
I am using strongly typed views in an MVC3 web app. I've noticed that when a form is submitted, the ViewModel that is passed to the controller only has values for properties that have form elements associated with them. For instance, the example below shows a simple confirmation View with a checkbox and a phone number that the user must confirm before proceeding. When the form is submitted to the controller action, the UserConfirmed property contains a value, but the PhoneNumber property is null.
Is there any way for the ViewModel to retain all of its values or do I have to repopulate the ViewModel properties that do not have form elements associated with them?
The View
#model WebMeterReplacement.ViewModels.Appointment.ScheduleConfirmationViewModel
#using (Html.BeginForm()) {
#Html.ValidationSummary(false)
#Html.CheckBoxFor(model => model.UserConfirmed)
<span>Please confirm before proceeding</span>
<div>
Phone Number: #Model.PhoneNumber
</div>
<input type="submit" value="Confirm"/>
The Controller
[HttpPost]
public ActionResult ScheduleConfirmation(ScheduleConfirmationViewModel model)
{
if (model.UserConfirmed)
{
// add ViewModel data to repository
}
else
{
ModelState.AddModelError("ERROR", WebResources.strERROR_ConfirmSchedule);
}
return View(model);
}
Since your writing the phonenumber as output to the page it won't be automatically posted back (you've found out that part) What you can do is populate an hidden or read-only field with the phonenumber so that it will be posted back to your controller. An second option is to make a new call to your datasource and repopulate your object before saving it back to your datasource.
I generally POST back information like this in a hidden input. I personally use this heavily to pass data needed to return the user exactly where they where before pressing edit.
In your case it's as simple as
#model WebMeterReplacement.ViewModels.Appointment.ScheduleConfirmationViewModel
#using (Html.BeginForm()) {
#Html.ValidationSummary(false)
#Html.CheckBoxFor(model => model.UserConfirmed)
<span>Please confirm before proceeding</span>
<div>
#Html.HiddenFor(m => m.PhoneNumber)
Phone Number: #Model.PhoneNumber
</div>
<input type="submit" value="Confirm"/>
For future reference:
If your passing complex objects back you need one hidden field per attribute (Hiddenfor does NOT iterate)
View
WRONG
#Html.HiddenFor(m => m.PagingData)
RIGHT
#Html.HiddenFor(m => m.PagingData.Count)
#Html.HiddenFor(m => m.PagingData.Skip)
#Html.HiddenFor(m => m.PagingData.PageSize)
Action
public HomeController(AViewModel Model)
{
PagingData PagingData = Model.PagingData;
Skip = PagingData.Skip;
}
If your passing Arrays you can do it like this
View
#if (Model.HiddenFields != null)
{
foreach (string HiddenField in Model.HiddenFields)
{
#Html.Hidden("HiddenFields", HiddenField)
}
}
Action
public HomeController(AViewModel Model)
{
String[] HiddenFields = Model.HiddenFields;
}
Well, the form will only POST elements that you have created. As you found out, simply writing the phone number out to the page will not suffice. The model binder can only bind those properties which exist in the posted data.
Generally you have a couple of options here:
1) You can create Input elements for all of the properties in your model, using visible elements (like a textbox) for those properties you want to edit, and hidden elements which should be posted back but have no UI
2) Post back a partial representation of your model (as you are doing now), read the entity back in from it's data source (I assume you're using some kind of data source, EF maybe) and then alter the properties of that entity with the ones from your form.
Both scenarios are common but it really depends on the complexity of your model.
I know this thread is a bit old, but thought I'd resurrect it to get feed back on my solution to this.
I'm in a similar situation where my objects are passed to a view, and the view may only display part of that object for editing. Obviously, when the controller receives the model back from the default model binder, and values not posted back become null.. and saving this means that a DB value becomes null just because it wasn't displayed/returned from a view.
I didn't like the idea of creating a model for each view. I know it's probably the right way... but I was looking for a reusable pattern that can be implemented fairly quickly.
See the "MergeWith" method... as this would be used to take a copy of the object from the database and merge it with the one returned from the view (posted back)
namespace SIP.Models
{
[Table("agents")]
public class Agent
{
[Key]
public int id { get; set; }
[Searchable]
[DisplayName("Name")]
[Column("name")]
[Required]
[StringLength(50, MinimumLength = 4)]
public string AgentName { get; set; }
[Searchable]
[DisplayName("Address")]
[Column("address")]
[DataType(DataType.MultilineText)]
public string Address { get; set; }
[DisplayName("Region")]
[Searchable]
[Column("region")]
[StringLength(50, MinimumLength = 3)]
public string Region { get; set; }
[DisplayName("Phone")]
[Column("phone")]
[StringLength(50, MinimumLength = 4)]
public string Phone { get; set; }
[DisplayName("Fax")]
[Column("fax")]
[StringLength(50, MinimumLength = 4)]
public string Fax { get; set; }
[DisplayName("Email")]
[RegularExpression(#"(\S)+", ErrorMessage = "White space is not allowed")]
[Column("email")]
[StringLength(50, MinimumLength = 4)]
public string Email { get; set; }
[DisplayName("Notes")]
[Column("notes")]
[DataType(DataType.MultilineText)]
public string Notes{ get; set; }
[DisplayName("Active")]
[Column("active")]
public bool Active { get; set; }
public override string ToString()
{
return AgentName;
}
public bool MergeWith(Agent a, string[] fields)
{
try
{
foreach (PropertyInfo pi in this.GetType().GetProperties())
{
foreach (string f in fields)
{
if (pi.Name == f && pi.Name.ToLower() != "id")
{
var newVal = a.GetType().GetProperty(f).GetValue(a,null);
pi.SetValue(this, newVal, null);
}
}
}
}
catch (Exception ex)
{
return false;
//todo: Log output to file...
}
return true;
}
}
}
And to use this in the controller.. you'd have something like..
[HttpPost]
public ActionResult Edit(Agent agent)
{
if (ModelState.IsValid)
{
Agent ag = db.Agents.Where(a => a.id == agent.id).ToList<Agent>().First<Agent>();
ag.MergeWith(agent, Request.Params.AllKeys);
db.Entry(ag).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
return View(agent);
}
This way, during post back, it takes the object from the database, and updates it with object from view... but only updates the values that were posted back.. So if you have a field like "address" or something that doesn't appear in the view.. it doesn't get touched during the update.
I've tested this so far and i works for my purposes, tho i welcome any feedback as I'm keen to see how others have overcome this situation. It's a first version and i'm sure it can be implemented better like through an extension method or something.. but for now the MergeWith can be copy/pasted to each model object.
Yes, Just place hidden fields in the form for those values which you are not using and want to return to server control.
Thanks