I'm trying to allow a user to set an association by looking up by name.
Unfortunately, even though I'm using virtual, ASP-MVC 4 is complaining that this is an invalid column name for this particular virtual field "VesselName". Here's the error:
Invalid column name 'VesselName'.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: Invalid column name 'VesselName'.
Here's my code:
public int VesselID { get; set; }
public virtual Vessel Vessel { get; set; }
public virtual string VesselName
{
get
{
return Vessel.Name;
}
set
{
if (value != null)
{
// make sure we use upper case
VesselID = db.Vessels.Where(v => v.Name.Equals(value.ToUpper())).First().ID;
}
}
}
You can have "virtual" or "unmapped" attributes in Entity framweork by using the [NotMapped] DataAnnotation. Virtual as used in the program refers to something else.
See virtual method tables.
http://en.wikipedia.org/wiki/Virtual_method_table
Related
I have a view that has one field that is editable.
My thought was to create an update query and map it to that view, but breeze is throwing an error when I call SaveChanges.
** Error **
TypeError: Cannot read property 'map' of undefined
at i._prepareSaveResult (breeze.min.js:formatted:5066)
at Object.it.AbstractDataServiceAdapter.i.saveChanges.n.ajax.success (breeze.min.js:formatted:4755)
at n (breeze.min.js:formatted:4818)
at angular.js:9408
at processQueue (angular.js:13248)
at angular.js:13264
at Scope.$get.Scope.$eval (angular.js:14466)
at Scope.$get.Scope.$digest (angular.js:14282)
at Scope.$get.Scope.$apply (angular.js:14571)
at done (angular.js:9698)
EDIT
My view is mapped to an entity
public partial class Shop
{
public Shop()
{
this.Notes = new HashSet<SoNote>();
}
public int SoId { get; set; }
public int DetailId { get; set; }
//[other properties removed for brevity]
public string ShopTech { get; set; }
public virtual OrderEdit OrderEdit { get; set; }
public virtual ICollection<SoNote> Notes { get; set; }
}
}
SoId and DetailId are my key and I want the user to be able to update ShopTech.
This is using model first.
I'm not sure this error is the actual root cause. How is your view defined and what kind of database are you using? There are restriction on the database as far as updating a view is concerned. In most cases views are read-only and a SQL update statement against it will fail. Certain types of views are editable. For the other cases, EntityFramework 6 allows you to define insert/update/delete stored procedures. Have you defined an update stored procedure? As long as EF is able to update your entity, Breeze should be just fine with that.
Here's more info on using stored procs with code first. https://msdn.microsoft.com/en-us/data/dn468673.aspx
I'm really trying hard to put everything on my project to work with the EF, but it's really getting difficult and sometimes it makes me wonder if it's really the smart move (to rely on EF against coding all the ins and outs of the database).
Well, my problem is still related to 1-N creating/editing/deleting functionality (something that should be simple, right?).
Ok, I'm pasting here some simple equivalent of my code.
For the Entities, I got the main class as:
[Table("OLIM_LOTE")]
public class Lote
{
[Key]
[Column("LOTE_ID_LOTE")]
public int? IDLote { get; set; }
[Column("LOTE_TX_OBS")]
public string Obs {get;set;}
[Column("LOTE_TX_DOCUMENTO_EXTRA")]
public string DocumentoExtra { get; set; }
[NotMapped]
public List<DocumentoLote> Documentos { get; set; }
public void LoadLists()
{
OlimpiqueDBContext myDbContext = new OlimpiqueDBContext();
var docs = (from doc in myDbContext.DocumentosLote
where doc.IDLote == this.IDLote
select doc);
this.Documentos = docs.ToList<DocumentoLote>();
}
}
[Notice that i used the nullable int? for Key - otherwise it throws me validation exception asking for a value on creation]
For the child class, i got this:
[Table("OLIM_DOCUMENTO_LOTE")]
public class DocumentoLote
{
[Key]
[Column("DOLO_ID_DOCUMENTO_LOTE")]
public int? IDDocumentoLote { get; set; }
[Column("DOCU_ID_DOCUMENTO")]
[ForeignKey("Documento")]
public int IDDocumento { get; set; }
public virtual Documento Documento { get; set; }
[Column("LOTE_ID_LOTE")]
[ForeignKey("Lote")]
public int IDLote { get; set; }
public virtual Lote Lote { get; set; }
}
[Notice that the child class has a reference back to the owner class, which are the "IDLote" and "Lote" attributes, and the owner class has a list of child class instances - so I got i bi-directional refernce - I assume that this is somehow related to the problems]
I got a Controller and View generated automatically by VS2012 with Read/Write functionality related to the class Lote.
What I did in the View can be described as: I used a Jquery DataTable to manage the child class data (the user can add "N" instances on the DataTable). I substituted the Post Button with a call to a JS method that simply gets all the data from the Form and from the DataTable and wrap it in a JSon object and send it to the controller via Ajax.
The controller method that receives it can be simplified as below:
[HttpPost]
public JsonResult Edit(Lote lote)
{
try
{
if (ModelState.IsValid) //<< HAVING PROBLEMS HERE... DETAILS BELOW
{
if (lote.IDLote.HasValue)
{
//Separete updates/inserts from deletes
List<int?> dbDocs = db.DocumentosLote
.Where(dt => dt.IDLote == lote.IDLote)
.Select(dt => dt.IDDocumentoLote)
.ToList();
List<int?> postedDocs = lote.Documentos
.Select(pt => pt.IDDocumentoLote)
.ToList();
List<int?> deletedDocs = dbDocs
.Except(postedDocs).ToList();
//Perform deletes
foreach (var delDocId in deletedDocs)
{
if (delDocId.HasValue)
{
DocumentoLote delDoc = db.DocumentosLote
.Where(dt => dt.IDLote == lote.IDLote && dt.IDDocumentoLote == delDocId)
.Single();
db.Entry(delDoc).State = EntityState.Deleted;
}
}
//Perform insert and updates
foreach (var doc in lote.Documentos)
{
if (doc.IDDocumentoLote.HasValue)
{
db.Entry(doc).State = EntityState.Modified;
}
else
{
db.Entry(doc).State = EntityState.Added;
doc.IDLote = (int)lote.IDLote;
}
}
}
else
{
db.Lotes.Add(lote);
}
db.SaveChanges();
// If Sucess== 1 then Save/Update Successfull else there it has Exception
return Json(new { Success = 1, ex = "" });
}
else
{
return Json(new { Success = 0, ex = "Falha ao tentar salvar os dados" });
}
}
catch (Exception ex)
{
// If Sucess== 0 then Unable to perform Save/Update Operation and send Exception to View as JSON
return Json(new { Success = 0, ex = ex.Message.ToString() });
}
}
Problems: Well I really passed through a lot to got to this point and now, I got only 2 problems. The first being that the creation is throwing a Validation Exception sayin that it needs an IDLote (for the child classes - but anyway, how would i have it if the owner class itself still doesn't have an Id at that point in creation?)
Second problem: Deletion dont work at all! Doesn't matter how i code it, it throws the exception "objects cannot be defined because they are attached to different ObjectContext objects". I really feel that this has something to do with the bidirectional reference between owner-children classes, but still, don't have a clue on exactly whats happening and how to solve it
I'm starting to feel really lost here. Any ideas on this would be very appreciated. Thanks
As there are a lot of views on this old question and now I do have some answer, I'm posting them for reference:
Q - Regarding the int? type for the key attributes:
A - It doesn't have to be a nullable int at all. The entity can be declared with a simple int attribute as key and when posting the JSon object from the View, back to some controller method, this attribute (the key) can be filled with the value "0". EF will generate the correct value as soon as it persists the object.
Q - Regarding the navigational attributes and how to implement the relation between the two classes when neither of them have already got a value (non-zero) on theis keys:
A - The JSon object to be sent back can implement the exact navigational relationaship between them. Wehn the controller binds the data posted to the model it should be receiving, it will "understand" their relationship and as soon as the values for the keys are generated, they will correctly reference one another.
Q - Regarding the error described on the delete method attempts:
A - When objects should interact with other objects, and those interactions should be persisted or "understood" by EF in any way, they must have been obtained, generated or attached to a same DBContext. EF rely on the DB context to create a tree of this interactions, thus, rendering impossible to build this tree when objets are not present on the same DB Context.
This is the problem that we're facing in .NET MVC 2.
We're trying to use DataAnnotations to take care of the Model Validation for us, like it's supposed to. The only problem that we're having is that we don't want the standard error messages (because we have multiple languages on our website).
We want to localize this, but the way the site is setup, is that all text comes from a database. So we'd like to have our error messages in the database as well.
So we wrote a custom RequiredAttribute, like this:
public class LocalizedRequiredAttribute : RequiredAttribute
{
public string LocalizedErrorMessage
{
get
{
return ErrorMessage;
}
set
{
ErrorMessage = value.Translate();
}
}
}
We wrote an extension to the String class to add the "Translate()" method, which does the necessary database lookup for the correct localized version.
We use our attribute like this:
[LocalizedRequired(LocalizedErrorMessage = "Naam is required")]
public string Name {get; set; }
This works, but only once.
If you visit the site in French first, you'll see the French error message stating that you're supposed to enter a value. If you visit the English site later, you'll still see the French error on the English page. The Setter seems to be called only once.
What can we do to prevent this behavior and refresh the error message every time the validation is run / the model is populated with values?
Thanks for any help you can give me.
Couldn't you fix this by moving your .Translate() from your setter to your getter? It makes sense that your setter is called only once.
Edit:
I assumed ErrorMessage was a virtual message, which is not the case.
Your only option might be to create Resource class (you don't need a resource file) that retrieves your values from the database.
[Required(ErrorMesageResourceName="FirstName", ErrorMessageResourceType=typeof(ABCResourceClass))]
public string Name {get; set; }
class ABCResourceClass{
public static String FirstName{
get{
return Translate("FirstName");
}
}
}
As you can infer from the example, the annotations framework calls the property with the name that matches the string you provide to ErrorMessageResourceName.
You could resort to some kindof code generation technique to create the ABCResourceClass if you have a lot of properties.
Just use method FormatErrorMessage() (whis is called everytime) to set ErrorMessage property
But it's hackish
public class ErrorLocalizedRequiredAttribute : RequiredAttribute
{
public ErrorLocalizedRequiredAttribute(string name)
{
Name = name;
}
public string Name
{ get; set; }
public override string FormatErrorMessage(string name)
{
//get translation from DB by Name
ErrorMessage = Localization.Translate(Name);
return base.FormatErrorMessage(name);
}
}
.
.
.
[ErrorLocalizedRequiredAttribute("EmailIsRequired")]
public string Email
{
get; set;
}
I am using Reflection provider for my WCF Data Service and my Data Context object has two key members, say EmpId and DeptId.
If I specify [DataServiceKey("EmpId", "DeptId")], the service doesn't work. When I try to access the collection with the URL http://localhost:55389/DataService.svc/EmployeeData, I get the following error:
The XML page cannot be displayed
Cannot view XML input using XSL style
sheet. Please correct the error and
then click the Refresh button, or try
again later. The following tags were
not closed: feed. Error processing
resource
'http://localhost:55389/DataService.svc/EmployeeData'.
With single member in the DataServiceKey, it works fine. I tried with Custom Data Provider and I could achieve this functionality. But if I can do it with the Reflection provider, that would be great.
I don't think the problem is the multiple keys. To confirm please use for example Fiddler or something similar to grab the whole response from the server and share the error in it (as I'm sure there will be one in there).
Guessing from the description I think the problem is that one of your key property values is null. That is not supported and would cause so called in-stream error which would leave the response XML incomplete (which seems to be your case).
OData can handle multiple keys but all keys must have a valid value. Review this for OData's rule. If you want to retrieve an entry with EmpId=1 and DeptId=someString, you should reconstruct your URI into something like:
http://localhost:55389/DataService.svc/EmployeeData(EmpId=1,DeptId='someString')
Be careful in OData queries because they are case sensitive.
That is weird, I just tried this:
public class Context
{
public IQueryable<Person> People {
get {
return (new List<Person> {
new Person { EmpId = 1, DeptId = 2, Name = "Dude" }
}).AsQueryable();
}
}
}
[DataServiceKey("EmpId", "DeptId")]
public class Person
{
public int EmpId { get; set; }
public int DeptId { get; set; }
public string Name { get; set; }
}
public class WcfDataService1 : DataService<Context>
{
// This method is called only once to initialize service-wide policies.
public static void InitializeService(DataServiceConfiguration config)
{
config.SetEntitySetAccessRule("*", EntitySetRights.AllRead);
config.DataServiceBehavior.MaxProtocolVersion =
DataServiceProtocolVersion.V2;
}
}
And it works just fine, do you notice any major differences?
-Alex
When I use UpdateModel or TryUpdateModel, the MVC framework is smart enough to know if you are trying to pass in a null into a value type (e.g. the user forgets to fill out the required Birth Day field) .
Unfortunately, I don't know how to override the default message, "A value is required." in the summary into something more meaningful ("Please enter in your Birth Day").
There has to be a way of doing this (without writing too much work-around code), but I can't find it. Any help?
EDIT
Also, I guess this would also be an issue for invalid conversions, e.g. BirthDay = "Hello".
Make your own ModelBinder by extending DefaultModelBinder:
public class LocalizationModelBinder : DefaultModelBinder
Override SetProperty:
base.SetProperty(controllerContext, bindingContext, propertyDescriptor, value);
foreach (var error in bindingContext.ModelState[propertyDescriptor.Name].Errors.
Where(e => IsFormatException(e.Exception)))
{
if (propertyDescriptor.Attributes[typeof(TypeErrorMessageAttribute)] != null)
{
string errorMessage =
((TypeErrorMessageAttribute)propertyDescriptor.Attributes[typeof(TypeErrorMessageAttribute)]).GetErrorMessage();
bindingContext.ModelState[propertyDescriptor.Name].Errors.Remove(error);
bindingContext.ModelState[propertyDescriptor.Name].Errors.Add(errorMessage);
break;
}
}
Add the function bool IsFormatException(Exception e) to check if an Exception is a FormatException:
if (e == null)
return false;
else if (e is FormatException)
return true;
else
return IsFormatException(e.InnerException);
Create an Attribute class:
[AttributeUsage(AttributeTargets.All, Inherited = false, AllowMultiple = false)]
public class TypeErrorMessageAttribute : Attribute
{
public string ErrorMessage { get; set; }
public string ErrorMessageResourceName { get; set; }
public Type ErrorMessageResourceType { get; set; }
public TypeErrorMessageAttribute()
{
}
public string GetErrorMessage()
{
PropertyInfo prop = ErrorMessageResourceType.GetProperty(ErrorMessageResourceName);
return prop.GetValue(null, null).ToString();
}
}
Add the attribute to the property you wish to validate:
[TypeErrorMessage(ErrorMessageResourceName = "IsGoodType", ErrorMessageResourceType = typeof(AddLang))]
public bool IsGood { get; set; }
AddLang is a resx file and IsGoodType is the name of the resource.
And finally add this into Global.asax.cs Application_Start:
ModelBinders.Binders.DefaultBinder = new LocalizationModelBinder();
Cheers!
With the DefaultModelBinder it is possible to override the default required error message but unfortunately it would apply globally which IMHO renders it completely useless. But in case you decide to do it here's how:
Add the App_GlobalResources folder to your ASP.NET site
Add a resources file called Messages.resx
Inside the resources file declare a new string resource with the key PropertyValueRequired and some value
In Application_Start add the following line:
DefaultModelBinder.ResourceClassKey = "Messages";
As you can see there's no link between the model property you are validating and the error message.
In conclusion it is better to write custom validation logic to handle this scenario. One way would be to use a nullable type (System.Nullable<TValueType>) and then:
if (model.MyProperty == null ||
/** Haven't tested if this condition is necessary **/
!model.MyProperty.HasValue)
{
ModelState.AddModelError("MyProperty", "MyProperty is required");
}
I've been using the awesome xVal validation framework. It lets me do all my validation in the model (Even LINQ-SQL :)). It also emits the javascript required for client side validation.
EDIT: Sorry left out the link for how to get it working for LINQ-SQL
The basic workflow goes something like this.
public partial class YourClass
{
[Required(ErrorMessage = "Property is required.")]
[StringLength(200)]
public string SomeProperty{ get; set; }
}
try
{
// Validate the instance of your object
var obj = new YourClass() { SomeProperty = "" }
var errors = DataAnnotationsValidationRunner.GetErrors(obj);
// Do some more stuff e.g. Insert into database
}
catch (RulesException ex)
{
// e.g. control name 'Prefix.Title'
ex.AddModelStateErrors(ModelState, "Prefix");
ModelState.SetModelValue("Prefix.Title", new ValueProviderResult(ValueProvider["Prefix.Title"].AttemptedValue, collection["Prefix.Title"], System.Globalization.CultureInfo.CurrentCulture));
}
how about this?
[RegularExpression(#"^[a-zA-Z''-'\s]{1,40}$",
ErrorMessage = "Characters are not allowed.")]
That should allow you to tag properties with specific error messages for whatever MVC validators you want to use...
In ASP.NET MVC 1, I met this problem too.
In my project, there is a model or business object named "Entry", and its primary key EntryId is int? type, and the value of EntryId can be allowd to input by users.
So the problem is, when the field is blank or zero or some integer value that has existed, the custom error messages can be shown well, but if the value is some non-integer value like "a", i can not find a way to use the custom message to replace the default message like "The value 'a' is invalid".
when i track the error message in ModelState, i found when the value is non-integer, there will be two errors related to EntryId, and the first item's error message is blank...
Now i have to use such an ugly code to hack the problem.
if (ModelState["EntryId"].Errors.Count > 1)
{
ModelState["EntryId"].Errors.Clear(); //should not use ModelState["EntryId"].remove();
ModelState.AddModelError("EntryId", "必须为大于0的整数"); //必须为大于0的整数 means "it should be an integer value and great than 0"
}
but this makes controller fat, hope there is a real solution to solve it.
Look up ModelState.AddError.
yes, there is a way, you must use System.ComponentModel.DataAnnotations in combination with xVal and you are going to be able to set validation rules and messages (u can even use resource files for localization) for each of your property using Attributes
look here http://blog.codeville.net/2009/01/10/xval-a-validation-framework-for-aspnet-mvc/