Access data from Model in Controller? - asp.net-mvc

I have a model for displaying a list of latest articles, and I would like to be able to define how many articles are displayed. I have created a property called DisplayNumberOfPressArticles and I would like to be able to access the value of this property from my controller.
Here is the model:
using Site.Helpers.Selections;
using Site.Models.Blocks.Data;
using EPiServer.DataAnnotations;
using EPiServer.Shell.ObjectEditing;
using System.ComponentModel.DataAnnotations;
namespace Site.Models.Blocks
{
[SiteContentType(GUID = "884202C2-61F1-4DF5-85A7-DC3D4E493F59")]
[SiteImageUrl]
public class LastArticlesTeaserBlock : SiteBlockData, PressOverviewData, ISpaceableData
{
[CultureSpecific]
public virtual string Heading { get; set; }
[Range(1, 1000)]
public virtual int DisplayNumberOfPressArticles { get; set; }
}
}
In my controller, I would like to take the value of DisplayNumberOfPressArticles as a limit for the .Take() query:
using System;
using System.Collections.Generic;
using Site.Models.Blocks;
using EPiServer.Web.Mvc;
using System.Web.Mvc;
using Site.Models.Pages;
using Site.Models.ViewModels;
using EPiServer.Find;
using EPiServer.Find.Api;
using EPiServer.Find.Cms;
using EPiServer.Find.Framework;
using EPiServer.Logging;
using ILogger = EPiServer.Logging.ILogger;
using EPiServer.Globalization;
namespace Site.Controllers
{
public class LastArticlesTeaserBlockController : BlockController<LastArticlesTeaserBlock>
{
private static readonly ILogger Logger = LogManager.GetLogger();
public override ActionResult Index(LastArticlesTeaserBlock currentContent)
{
var model = new LastArticlesTeaserViewModel
{
Headline = currentContent.Heading,
ArticlePages = GetArticlePages(),
PaddingTop = currentContent.PaddingTop,
PaddingBottom = currentContent.PaddingBottom
};
return PartialView(model);
}
private List<PressDetailsPage> GetArticlePages()
{
List<PressDetailsPage> result = new List<PressDetailsPage>();
IClient findClient = SearchClient.Instance;
var search = findClient.Search<PressDetailsPage>();
search = search
.Filter(sp => sp.IsDeleted.Match(false)).PublishedInCurrentLanguage()
.Filter(sp => sp.Headline.Exists() | sp.Description.Exists())
.Filter(sp => sp.Language.Name.Match(ContentLanguage.PreferredCulture.Name))
.OrderByDescending(sp => sp.PublishDate, SortMissing.Last)
.Take(??);
try
{
var searchResult = search.GetContentResult();
result.AddRange(searchResult);
}
catch (NullReferenceException e)
{
Logger.Error(e.ToString());
}
return result;
}
}
}
Sorry for the newbie question, but everything I have tried hasn't worked so far. I thought I could access the model by using .Take(LastArticlesTeaserBlock.DisplayNumberOfPressArticles);

How about changing your signature to something like GetArticlePages(int maxCount) and then invoking it like ArticlePages = GetArticlePages(currentContent.DisplayNumberOfPressArticles) in your Index method?

Your SearchClient class looks like a custom implementation and hard to tell if the bug is there.
Option 1:
Something like -- db.ArticleSet.OrderByDescending(t => t.Articles.Count).Take(10);
Option 2:
Or a more direct query.
Make life easier and break it down in two parts firs the query, they execution, then put it back together if you want.
Step 1
var articlesQuery = from x in Articles..
where x.IsDeleted == true ....
Step 2
var limitedArticlesQuery = articlesQuery.Take(25);
From client size send a int pageSize
var pagedProductQuery = articlesQuery.Skip(10 * pageSize).Take(10)

Related

Attribute routing for two actions leads to a "Not valid OData path template"

So i have two functions that return a customer, which get feeded by two different parameters. One being the ID of the customer and the other being his customer number.
My controller:
using System.Linq;
using System.Net;
using System.Web.Http;
using System.Web.OData;
using System.Web.OData.Routing;
using Models;
using AutoMapper;
using AutoMapper.QueryableExtensions;
using System.Web.OData.Extensions;
using Importing;
using Objects;
using Microsoft.OData;
namespace Controllers
{
public class CustomersController : ODataController
{
// GET: CustomerByCNO(5)
[HttpGet]
[ODataRoute("CustomerByCNO({key})")]
[EnableQuery]
public SingleResult<CustomerDTO> GetCustomerByCNO([FromODataUri]string key)
{
Import i = new Import();
var customer = i.GetCustomer(key).ProjectTo<CustomerDTO>().AsQueryable();
return SingleResult.Create(customer);
}
// GET: Customer(5)
[HttpGet]
[ODataRoute("Customer({id})")]
[EnableQuery]
public SingleResult<CustomerDTO> Get([FromODataUri]int id)
{
Import i = new Import();
var customer = i.GetCustomer(id).ProjectTo<CustomerDTO>().AsQueryable();
return SingleResult.Create(customer);
}
}
}
Initialization:
using AutoMapper;
using Models;
using Objects;
using System.Web.Http;
using System.Web.OData.Builder;
using System.Web.OData.Extensions;
using Microsoft.OData.Edm;
namespace API
{
public static class WebApiConfig
{
public static void ConfigureAPI(HttpConfiguration config)
{
config.MapODataServiceRoute(
routeName: "odata",
routePrefix: "",
model: GetEdmModel()
);
config.EnsureInitialized();
}
private static IEdmModel GetEdmModel()
{
ODataConventionModelBuilder builder = new ODataConventionModelBuilder
{
Namespace = "Controllers",
ContainerName = "DefaultContainer"
};
builder.EntitySet<CustomerDTO>("Customer")
.EntityType.HasKey(c => c.Id)
.CollectionProperty(c => c.CustomFields);
var edmModel = builder.GetEdmModel();
return edmModel;
}
}
}
While the second functions works as intended the first functions does not and the EnsureInitialized() function throws an InvalidOperationException saying, that it is no valid OData path template and that no resource has been found. How can i get this to work? Not quite sure what i am missing here.
UPDATE 1:
Changing the Controller method to this:
[HttpGet]
[ODataRoute("CustomerByNo(No={no})")]
public SingleResult<CustomerDTO> CustomerByNo([FromODataUri] int no)
{
Import i = new Import();
var customer = i.GetCustomer(no.ToString()).ProjectTo<CustomerDTO>().AsQueryable();
return SingleResult.Create(customer);
}
with this additional line in the config:
builder.Function("CustomerByNo").Returns<SingleResult<CustomerDTO>>().Parameter<int>("No");
Made it so i can access the functions at least. I had to change the parameter to an int as well, seems like it doesnt like strings? However the return value is not deserialized and shown as usual. Also if i leave the [EnableQuery] line in the method declaration, the call will crash saying that it doesnt know how to deserialize since it is not bound to the entityset of Customer i guess.
Trying it this way however, leads to the original error message, that the resource could not be found:
builder.EntityType<CustomerDTO>().Collection.Function("CustomerByNo").Returns<SingleResult<CustomerDTO>>().Parameter<int>("No");
You have to declare your custom odata functions in the convention model:
FunctionConfiguration customerByCNOFunction = builder.Function("CustomerByCNO");
customerByCNOFunction.Returns<CustomerDTO>();
customerByCNOFunction.Parameter<string>("key");
Update :
My first answer was for declaring a functions that returns a type not queryable in odata.
To enable query, the function needs to return an odata entity from an entity set :
builder.Function("CustomerByNo").ReturnsFromEntitySet<CustomerDTO>("Customer").Parameter<int>("No")

How might I simultaneously bind FromQuery and FromRoute parameter?

I am needing to simultaneously support a query-parameter based route (/api/models?id=1) and a route based one (/api/models/1) while still allowing unambiguous access to the models collection (/api/models)?
My controller looks (something) like this:
[Route("/api/{controller}")]
public class ModelsController : Controller
{
[HttpGet]
public Models[] GetModels([FromQuery]QueryOptions queryOptions)
{
//...
}
[HttpGet("{id:int}")]
public Model Get([FromRoute] int id)
{
//...
}
[HttpGet("?{id:int}")]
public Model Get2Try1([FromQuery] int id)
{
//Fails with ": The literal section '?' is invalid.
//Literal sections cannot contain the '?' character."
//Which makes sense after some reading...
}
[HttpGet]
public Model Get2Try2([FromQuery] int id)
{
//Fails with "AmbiguousActionException: Multiple actions matched.
//The following actions matched route data and had all constraints satisfied:
//GetModels and Get2Try2"
//Which I think I understand as well...the absence of optional params
//means ambiguous routing...
}
[HttpGet] //What here?
public Model Get2Try3([FromQuery] int id) //and/or here?
{
}
}
I feel like there should be some way to (with declarative routing) accomplish this. Has anyone done anything along these lines?
Also, current code base is ASP.NET Core (RC1) to be upgraded to RTM/1.0 shortly. Details on either side are likely similar, but am interested in either/both.
I've found that the following works:
[HttpGet, Route("{id?}")]
... the key being mainly the '?'. You don't need any [FromX] in the method signature, this does the trick and caters for both query string and route parameter passing.
Unfortunately Swagger UI doesn't like it and expects some explicit parameter to work out of the box (https://github.com/domaindrivendev/Ahoy/issues/47 or https://github.com/domaindrivendev/Ahoy/issues/182), but that's another story :)
I had the same problem.
There aren't solutions that works (against wep api .net) with web api core.
If we set [Route("{id}")] and [Route("")] doesn't work; if we set only [Route("{id?}")] the query parameter is empty if I use querystring.
So, I've used a workround.
I used [Route("{id?}")], but inside the function I get param from Request.Query
Example
public T Cast<T>(string input)
{
T output = default(T);
if (string.IsNullOrWhiteSpace(input))
return output;
input = input.Trim();
try
{
Type typeToCastTo = typeof(T);
if (typeof(T).IsGenericType)
typeToCastTo = typeToCastTo.GenericTypeArguments[0];
if (typeToCastTo.IsEnum)
{
if (Enum.IsDefined(typeToCastTo, input))
return (T)Enum.Parse(typeToCastTo, input);
return output;
}
object value = Convert.ChangeType(input, typeToCastTo, CultureInfo.InvariantCulture);
return (value == null) ? output : (T)value;
}
catch
{
return output;
}
}
public void MapQuerystringParams<T>(ref T param, string name)
{
var q = Request.Query[name].FirstOrDefault();
if (q != null)
{
var cast = Cast<T>(q);
if (!cast.Equals(default(T)))
param = cast;
}
}
[Route("api/[controller]/[action]")]
[ApiController]
public class ActivityController : ControllerBase
{
//examples of call
//https://localhost:44345/api/Activity/GetActivityByCode/7000
//https://localhost:44345/api/Activity/GetActivityByCode/?Id=7000
[HttpGet]
[Route("{Id?}")]
public IActionResult GetActivityByCode(int Id)
{
MapQuerystringParams(ref Id, "Id"); //this take param from querystring if exists
ActivityBusiness business = new ActivityBusiness(new BusinessInitializer { config = configuration });
ActivityDTOModel activity = business.GetActivityByCode(Id);
return Ok(activity);
}
}
Ideally in the domain design if you can have one method serving one specific function then great. Recently I had to faithfully implement a legacy API and it wasn't an option for me to decompose the design of my API.
If you are suffering from ambiguous routes in MVC6 and need to differentiate unique Routes given specific QueryStrings that have been supplied at one single POST method. Then IActionConstraint can help! Here is some example code of me using it :
using System;
using Microsoft.AspNetCore.Mvc.ActionConstraints;
namespace Automation.Api.Service.Attributes
{
public class RoutingSpecificAttribute : Attribute, IActionConstraint
{
private string _keyParam;
public RoutingSpecificAttribute(string routingParameter)
{
this._keyParam = routingParameter;
}
public int Order
{
get
{
return 0;
}
}
public bool Accept(ActionConstraintContext context)
{
if (this._keyParam == null) { return true; }
switch (this._keyParam)
{
case "name": return context.RouteContext.HttpContext.Request.Query.ContainsKey(this._keyParam);
case "noquerystring": return context.RouteContext.HttpContext.Request.Query.Count == 0;
default:
return false;
}
}
}
}
This one method in the API that I needed to author both serviced a separate create + update functions based on the existence of a couple of QueryStrings: name & version.
So to help disambiguate you can distinctly decorate each of the methods within your controllers within said controller class [RoutingSpecific("noquerystring")] or [RoutingSpecific("name")] to help differentiate.
MSDN class description
Example implementation - see Entropy github
For anyone that happens to stumble upon this as I have,
Using .Net Core 3.1 the following works:
Web Controller Method
[HttpGet("something/{id}")]
public IActionResult Get([FromRoute] id, [FromQuery] OptionalParams optionalParams)
{
// do stuff
}
Query Parameter Container
public class OptionalParams
{
[FromQuery(Name = "colour_of_thing")]
public string Colour { get; set; }
[FromQuery(Name = "shape_of_thing")]
public string Shape { get; set; }
[FromQuery(Name = "some_other_filter")]
public string SomeOtherFilter { get; set; }
}
Url
var id = Guid.NewGuid();
var colour = "red";
var shape = "circle";
var url = $"Http://localhost:5000/something/{id}?colour_of_thing={colour}&shape_of_thing={shape}";

Want to save selected (i.e., more than 1) enums as string with NHibernate

I cannot for the life of me get this to work with my existing code, but I am trying to save my enum selections as strings in NHibernate. Basically, I have a UI check box and if the user selects multiple check boxes I want to store those selections. Now, I can get NHibernate to store ONE selection (e.g., from a drop down or radio button list, where the user is limited to one choice only).
This is the jist of what I have for an enum:
public enum IncomeType
{
[Display(Name = "Full-Time Employment")]
FullTime,
[Display(Name = "Part-Time Employment")]
PartTime,
[Display(Name = "Self-Employment")]
SelfEmployed,
[Display(Name = "Rental")]
Rental,
[Display(Name = "Social Security Payments")]
SocialSecurity,
[Display(Name = "Retirement / Pension Payments")]
Retirement,
[Display(Name = "Child Support Payments")]
ChildSupport,
[Display(Name = "Spousal Maintenance")]
Maintenance,
[Display(Name = "Other")]
Other
}
I use a method to "select" whether a checkbox list is shown (if my BulkItemThreshold equals the number of options, a checkbox list is displayed). Here is that method:
public static IEnumerable<SelectListItem> GetItemsFromEnumString<T>
(T selectedValue = default(T)) where T : struct
{
return from name in Enum.GetNames(typeof(T))
let enumValue = Convert.ToString((T)Enum.Parse(typeof(T), name, true))
select new SelectListItem
{
Text = GetEnumDescription(name, typeof(T)),
Value = enumValue,
Selected = enumValue.Equals(selectedValue)
};
}
(Note: some items in there are helpers, but I don't believe they are relevant; also, the selected input is displayed using a template .cshtml file - again, not sure if that's relevant)
Now, I call this thusly:
public class IncomeTypeSelectorAttribute : SelectorAttribute
{
public override IEnumerable<SelectListItem> GetItems()
{
return Selector.GetItemsFromEnumString<IncomeType>();
}
}
And finally, we get to the virtual property (using a proxy) but this is where NHibernate throws a wrench (Note: this was working fine for me before NHibernate, and now I am trying to get many lines of code working with it WITHOUT having to re-do everything; if I re-do everything I will probably triple the code I already have to get it to work):
Property (record):
[IncomeTypeSelector(BulkSelectionThreshold = 9)]
public virtual List<string> IndividualIncomeTypeCheckBox { get; set; }
proxy (part):
public List<string> IndividualIncomeTypeCheckBox
{
get { return Record.IndividualIncomeTypeCheckBox; }
set { Record.IndividualIncomeTypeCheckBox = value; }
}
Again, this is how I was doing things and it was working great before NHibernate. But now I have to use NHibernate. No getting around it.
I am using a service class that it tying the two together in a Create method to save in the DB with NHibernate, and for the above it would ordinarily look like this:
part.IndividualIncomeTypeCheckBox = record.IndividualIncomeTypeCheckBox;
This would work if it were just one selection.
Well, I've spent a good two (2) months trying to get this to work. It's tough because I have lots of code where the user can make only one selection (such as with a radiobutton list) and it works GREAT - even with NHibernate. Let me give you an example:
public virtual IncomeType? IndividualIncomeTypeCheckBox { get; set; }
If I do the above, it will display a drop down list, and NHibernate will store the ONE allowable option selected by the user in the DB no problem. But more than one option with List<string> does not work.
Now, I have tried everything I could find here or elsewhere and nothing works. Yes, I know it should be IList<IncomeType> or some other variant. But if I use this then NHibernate requires that IncomeType be another table in the DB. This is too much code to write for such a simple thing I believe. We are not talking a many-to-many relation in the sense that this is not a User with Multiple addresses (wherein addresses would have street, city, state, zip, etc.).
I have tried different types of proxy get and set code, but nothing works. I have tried [Flags] and other things working with string only, but to no avail. Those last solutions would "work" but ONLY to save the first item selected out of multiple (i.e., in my scenario, if the user selected "FullTime" and "Rental" as Income Types, then only "FullTime" (string) would be saved or "1" ([Flags]/int), not both items selected.
I have a situation where I re-display the choices using a ReadOnly attribute like this:
[IncomeTypeSelector]
[ReadOnly(true)]
public List<string> IndividualIncomeTypeCheckBoxPost
{
get { return IndividualIncomeTypeCheckBox; }
}
This would display on the UI, but I tried doing something like this with NHibernate and it wouldn't work.
Could anyone please show me, using the above, how I can go about getting NHibernate to store more than one enum in this checkbox list scenario?
UPDATE:
More poking around here and on the web, and I came up with the following (which still does not work).
Property (record):
[IncomeTypeSelector(BulkSelectionThreshold = 9)]
public virtual IList<IncomeTypeRecord> IndividualIncomeTypeCheckBox
{
get { return incomeType; }
set { incomeType= value; }
}
private IList<IncomeTypeRecord> incomeType =
new List<IncomeTypeRecord>();
Proxy (part):
public IList<IncomeTypeRecord> IndividualIncomeTypeCheckBox
{
get { return Record.IndividualIncomeTypeCheckBox; }
set { Record.IndividualIncomeTypeCheckBox= value; }
}
And a change to the enum:
public enum IncomeType : int // removing int & value still gives validate error
{
[Display(Name = "Full-Time Employment")]
FullTime = 1,
[Display(Name = "Part-Time Employment")]
PartTime,
....
}
And I added this class to support IncomeTypeRecord
public class IncomeTypeRecord
{
public virtual int Id { get; set; }
public virtual IncomeType Value { get; set; }
}
HOWEVER, when I get to the UI screen and pick one or more options I get a validation error (value not valid). For example, say I pick FullTime alone, or pick FullTime and Retirement, then the UI will display the following error:
The value 'FullTime' is invalid.
The value 'FullTime,Retirement' is invalid.
(respectively)
Even if I remove the int declaration for the enum and get rid of the value I started with "1", I still get this validation error. I tried messing around with and adding different model binders (which now has me stumped as to whether my original problem still exists and now I have a different problem - but you still get bounty points :) ).
Pulling my hair out. If I could offer more bounty I would. I need a definitive solution. I appreciate any help.
UPDATE
This is what I have so far:
Record:
public virtual string IndividualIncomeTypeCheckBox{ get; set; }
Part:
//If I do IEnumberable<string> my .Select throws a cast error
public IEnumerable<IncomeType> IndividualIncomeTypeCheckBox
{
get
{
return Record
.IndividualIncomeTypeCheckBox
.Split(',')
.Select(r => (IncomeType)Enum.Parse(typeof(IncomeType), r));
}
set { Record.IndividualIncomeTypeCheckBox= value
== null ? null : String.Join(",", value); }
}
Service Class:
public SimplePart CreateSimple(SimplePartRecord record)
{
SimplePart simple = Services.ContentManager.Create<SimplePart>("Simple");
...
//How I would save a FirstName property (example Part / PartRecord below)
//public virtual string FirstName { get; set; } - PartRecord
//public string FirstName - Part
//{
// get { return Record.FirstName ; }
// set { Record.FirstName= value; }
//}
simple.FirstName = record.FristName;
...
//I obviously cannot do the following with the above IncomeType
//Getting cannot convert string to IEnumerable error
//How would I write this:
simple.IndividualIncomeTypeCheckBox = record.IndividualIncomeTypeCheckBox;
...
}
And this is how it's called in a controller (this persists to DB): (Updating Controller code)
public ActionResult Confirm(string backButton, string nextButton)
{
if (backButton != null)
return RedirectToAction("WrapUp");
else if ((nextButton != null) && ModelState.IsValid)
{
_myService.CreateSimple(myData.SimplePartRecord);
return RedirectToAction("Submitted");
}
else
return View(myData);
}
Updating with additional code (serialization and view model):
"myData" is defined in the controller (using Serialization) as:
private MyViewModel myData;
protected override void OnActionExecuting(ActionExecutingContext filterContext)
{
var serialized = Request.Form["myData"];
if (serialized != null)
{
myData = (MyViewModel)new MvcSerializer().Deserialize
(serialized, SerializationMode.Signed);
TryUpdateModel(myData);
}
else
myData = (MyViewModel)TempData["myData"] ?? new MyViewModel();
TempData.Keep();
}
protected override void OnResultExecuted(ResultExecutedContext filterContext)
{
if (filterContext.Result is RedirectToRouteResult)
TempData["myData"] = myData;
}
I use Serialization because I set up a multi-step wizard (as seen in the controller action "backButton" "nextButton) on the front-end. I am not using a driver (which can only display Admin or on the front-end but then only on .cshtml files directly under the ~/Views folder (not in a structured folder list like I am using)). No driver = no update view model type code = no mechanism to "create" the data in the DB. If I do not use some "create" type method, the form will submit but all the data will be "NULL".
When you say that the data should be persisted automatically, I am sorry but I do not see how. All the stuff I read or code I review has SOME method of updating the DB with whatever is entered in a form. If I am missing something, my apologies.
"MyViewModel" is pretty straightforward:
[Serializabel]
public class MyViewModel
{
public SimplePartRecord SimplePartRecord { get; set; }
}
And, just in case, here is the relevant portion of the migration (return 1 is a completely separate and unrelated table):
public int UpdateFrom1()
{
SchemaBuilder.CreateTable("SimplePartRecord",
table => table
.ContentPartRecord()
...
.Column("IndividualIncomeTypeCheckBox", DbType.String)
...
);
ContentDefinitionManager.AlterPartDefinition("SimplePart",
part => part
.Attachable(false));
return 2;
}
The error I am getting is
Cannot implicitly convert type 'string' to 'System.Collections.Generic.IEnumerable'"
when I do the following in the "Create" method of my service class:
simple.IndividualIncomeTypeCheckBox = record.IndividualIncomeTypeCheckBox;
One additional thought: I tried using the n-n Relation sample to handle this scenario. Aside from it being a lot of extra code for what I thought should be straightforward and simple, because of the way I am using Serialization I had a lot of object reference errors and could not figure out how to properly code my controller to handle it.
There's a lot of info to wade through here so hopefully I haven't missed the point. It appears to me that the goals are:
The business class has a collection property of IList<IncomeType> without requiring an additional table
The values in that collection should be persisted as a delimited string of the enum names
The best approach is to use a custom user type (an implementation of NHibernate.UserTypes.IUserType) to map the property. Below is a generic IUserType that will map an enum of type T from an IList<T> property to a comma delimited string in the database and back again. There's no easy way to restrict T to an enum but the code will only work with enums.
Mapping a property using the custom type is simple with Fluent NHibernate:
public class Person
{
public Person()
{
IncomeTypes = new List<IncomeType>();
}
public virtual int PersonId { get; protected set; }
public virtual string FirstName { get; set; }
public virtual string LastName { get; set; }
public virtual IList<IncomeType> IncomeTypes { get; protected set; }
}
public class PersonMap : ClassMap<Person>
{
public PersonMap()
{
Table("Person");
Id(x => x.PersonId).GeneratedBy.Identity();
Map(x => x.FirstName);
Map(x => x.LastName);
Map(x => x.IncomeTypes).CustomType<EnumAsDelimitedStringType<IncomeType>>();
}
}
And here's the code for the user type:
public class EnumAsDelimitedStringType<T> : IUserType
{
public new bool Equals(object x, object y)
{
if (ReferenceEquals(x, y))
{
return true;
}
var xList = x as IList<T>;
var yList = y as IList<T>;
if (xList == null || yList == null)
{
return false;
}
// compare set contents
return xList.OrderBy(xValue => xValue).SequenceEqual(yList.OrderBy(yValue => yValue));
}
public int GetHashCode(object x)
{
return x.GetHashCode();
}
public object NullSafeGet(IDataReader rs, string[] names, object owner)
{
var outValue = NHibernateUtil.AnsiString.NullSafeGet(rs, names[0]) as string;
if (string.IsNullOrEmpty(outValue))
{
return new List<T>();
}
var getValueArray = outValue.Split(new[] {','}, StringSplitOptions.RemoveEmptyEntries);
return Array.ConvertAll(getValueArray, s => (T)Enum.Parse(typeof(T), s)).ToList();
}
public void NullSafeSet(IDbCommand cmd, object value, int index)
{
var inValue = value as IList<T>;
// set to string.Empty if you prefer to store that instead of null when the collection is null or empty
object setValue = null;
if (inValue != null && inValue.Any())
{
var setValueArray = Array.ConvertAll(inValue.ToArray(), v => Enum.GetName(typeof(T), v));
setValue = string.Join(",", setValueArray);
}
NHibernateUtil.AnsiString.NullSafeSet(cmd, setValue, index);
}
public object DeepCopy(object value)
{
return value;
}
public object Replace(object original, object target, object owner)
{
return original;
}
public object Assemble(object cached, object owner)
{
return cached;
}
public object Disassemble(object value)
{
return value;
}
public SqlType[] SqlTypes
{
get { return new[] {new SqlType(DbType.AnsiString)}; }
}
public Type ReturnedType
{
get { return typeof(IList<T>); }
}
public bool IsMutable
{
get { return false; }
}
}
I think you're on the right track pursuing a [Flags] enum. You may have done this, but just in case -- making an enum flags-worthy is more than adding the attribute. You also have to specify the value for the items in a binary-friendly manner. I've found the easiest way to do this is as follows:
[Flags]
public enum IncomeType : long // you'll need the room with several options
{
FullTime = 1,
PartTime = 1 << 1,
SelfEmployed = 1 << 2
// And so on
}
If you don't do this, then you'll get sequential integer values, which breaks the bitwise comparison that allows you to do multiple values in a single integer.
Your code to create the SelectList looks fine. Your options should construct form values that get posted back with the same name. If you want to use the default modelbinder, that means the associated property on your view model would need to be List<int>. If you're not using a view model (you probably should) you can pull it out of the forms collection.
Once you have this set up, then translating from your view model to your NHibernate entity is simple if a little annoying. You basically have to cycle through the values in the list and |= them onto your NHibernate entity's single enum property.
So let's assume you have a view model like this:
public class MyEditViewModel
{
public string Name { get; set; }
public List<int> IncomeSelections { get; set; }
// You'll probably have this to populate the initial view rendering
public SelectList AllIncomeOptions { get; set; }
}
You'll build your view using your helpers and all that, then build the checkboxes using the SelectList but making sure the input name is IncomeSelections, then when it's posted back you will push the view model data into your NHibernate entity something like this:
var myNHEntity = new NHEntity();
// If you're editing an existing entity, then be sure to reset the enum
// value to 0 before going into the following foreach loop...
foreach (var incomeSelection in viewModel.IncomeSelections)
{
myNHEntity.IncomeSelection |= incomeSelection;
}
There's probably a more clever way to do this, and you might have to cast the int to your enum type, but you'll figure that out (I'd do it for you, but it is Friday and I already have a beer open).
NHibernate should persist it without you having to do anything funky on the NH side.
In summary...
It seems like this is more a problem of how you handle the posted data than the NHibernate side. If you implement something like this, then be sure to use Fiddler or FireBug to inspect the posted values to make sure 1) they're integers and 2) the names are the same so they'll be added to the list.
Good luck!
The problem is simply that it won't be able to map a List without building a full relationship with an intermediate association table. It is way simpler to have the record store the values as a comma-separated string (so your record property is a string, not a list of string) and your part can map back and forth between string and List.
You can find an example of something very close here:
https://bitbucket.org/bleroy/nwazet.commerce/src/d722cbebea525203b22c445905c9f28d2af7db46/Models/ProductAttributesPartRecord.cs?at=default
https://bitbucket.org/bleroy/nwazet.commerce/src/d722cbebea525203b22c445905c9f28d2af7db46/Models/ProductAttributesPart.cs?at=default
It's not using enum values, instead it's a list of ids, but that should give you a good idea about how to make this work fairly simply: parsing enums you already know how to do.
Let me know if you need more details, but I think that's what you needed to get unblocked.

Linq casting Issue in EntityFramework

Hi,
I am new to Linq and entity framework. I am doing something like this
I have 3 viewmodel:
1.
public class FlowViewModel
{
..........................
public List<FlowLevelViewModel> Levels { get; set; }
}
public class FlowLevelViewModel
{
.........................
public List<BlockDetailsViewmodel> Blocks { get; set; }
}
public class BlockDetailsViewmodel
{
.......................
}
and from my controller I am calling the datalayer.
var model = new FlowViewModel();
model = dataOb.GetFlowForTheDocument(company, docType);
model = dataOb.GetFlowStageForTheDocument(model);
return model;
and in my datalayer
public FlowViewModel GetFlowStageForTheDocument(FlowViewModel model)
{
var flowlevelviewModel = (from p in dbContext.FlowStages
where p.FlowID == model.FlowId
select new FlowLevelViewModel()
{
.................
Blocks = GetBlockDetailsForTheDocument(p.StageID, .StageType)
}).ToList();
model.Levels = flowlevelviewModel;
return model;
}
public List<BlockDetailsViewmodel> GetBlockDetailsForTheDocument(int StageID, string stageType)
{
var blockDetails = new List<BlockDetailsViewmodel>();
......................................
return blockDetails;
}
While I am running the program I am getting this error:
**NotSupportedException Was unhandled by user Code**
LINQ to Entities does not recognize the method 'System.Collections.Generic.List`1[SEADViewModel.BlockDetailsViewmodel] GetBlockDetailsForTheDocument(Int32, System.String)' method, and this method cannot be translated into a store expression.
My project is in production stage so I have no time at all. Does anyone know what I am doing wrong?
This should solve your problem:
var data = (from p in dbContext.FlowStages
where p.FlowID == model.FlowId
select p).ToList();
var flowlevelviewModel = (from p in data
select new FlowLevelViewModel()
{
.................
Blocks = GetBlockDetailsForTheDocument(p.StageID, .StageType)
}).ToList();
Note that this will evaluate the query at the first ToList(). If you need to run the entire query at once, you need to build a simple LINQ expression, you can't use your method GetBlockDetailsForTheDocument inside the query. See #Tilak's answer for a link to supported build in methods.
You are using Linq to Entities.
It does not support all the functions. List of supported and non supported functions
You need to write custom model defined function GetBlockDetailsForTheDocument to use it in LINQ query.

How do you switch View Engines on the fly within an ASP.Net MVC Controller action?

I want to write a custom view engine that returns custom text (like coma delimited) does anyone know how I'd change the view engine on the fly to handle this?
I'd create a custom ActionResult. I use Json() function to return a JsonResult when I need JSON as response. I use this code to fill a ExtJS tree using JSON data.
public JsonResult Folders(string node)
{
var relativePath = (node == "root") ? "" : node;
var path = Path.Combine(BASE_PATH, relativePath);
var folder = new DirectoryInfo(path);
var subFolders = folder.GetDirectories();
var folders = new List<ExtJsTreeNode>();
foreach (var subFolder in subFolders)
{
folders.Add(new ExtJsTreeNode(subFolder.Name, subFolder.FullName.Replace(BASE_PATH, ""), "folder"));
}
return Json(folders);
}
private class ExtJsTreeNode
{
public string text { get; set; }
public string id { get; set; }
public string cls { get; set; }
public ExtJsTreeNode(string text, string id, string cls)
{
this.text = text;
this.id = id;
this.cls = cls;
}
}
A sample of a custom ActionResult here.
Your controller shouldn't know or care about this, other than which View to send the data to. The View can render in any format imaginable. I've got views that emit RSS (XML), etc. In the controller, either send it to the default view or explicitly identify the target view.
If I understood your question correctly, you want to use different views based on the parameters passed to the controller. If so, you can use this statement in the controller action:
return View("ViewName");
Otherwise, please clarify your question.

Resources