Entity Framework 5 - LINQ syntax error - c#

I have the following code where I am creating a IList that I need to filter by the data in another list called List. The locations list represents the locations a user is allowed to view based on their permissions. I am new to LINQ and am confused with error I get (C# Unknown method "Where(?)" of "System.Ling.IQueryable". I have tried various syntax arrangement using either Contains() and Any() or both to no avail. I feel like it's something very basic that I don't understand about doing this. Here is the code:
----- users locations
using System;
using System.ComponentModel.DataAnnotations;
using System.Linq;
namespace Decking.Models
{
public class locations
{
[Key]
public string org_id { get; set; }
}
}
///////// here is the view model
using System.ComponentModel.DataAnnotations;
using System;
namespace Decking.Models
{
public class InventoryViewModel
{
[Key]
public int id { get; set; }
public DateTime metric_dt { get; set; }
public int? item_id { get; set; }
public int? loc_type_id { get; set; }
public string trlr_nbr { get; set; }
public string user_id { get; set; }
public string org_id { get; set; }
public Double numerator { get; set; }
//these are the child entities
[UIHint("ClientItem")]
public ItemViewModel Items
{
get;
set;
}
[UIHint("ClientLocTypes")]
public LocTypesViewModel LocTypes
{
get;
set;
}
[UIHint("ClientOrgsByUser")]
public OrgsByUserViewModel OrgsByUser
{
get;
set;
}
}
}
///////// code to populate the view model
public IList<InventoryViewModel> GetAll(List<locations> locs)
{
IList<InventoryViewModel> result = new List<InventoryViewModel>();
result = entities.inventory.Select(inventory => new
InventoryViewModel
{
id = inventory.id,
metric_dt = inventory.metric_dt,
item_id = inventory.item_id,
loc_type_id = inventory.loc_type_id,
trlr_nbr = inventory.trlr_nbr,
org_id = inventory.org_id,
numerator = inventory.numerator,
user_id = inventory.user_id,
Items = new ItemViewModel()
{
item_id = inventory.items.item_id,
item_desc = inventory.items.item_desc,
},
LocTypes = new LocTypesViewModel()
{
loc_type_id = inventory.loc_types.loc_type_id,
loc_desc = inventory.loc_types.loc_desc,
},
OrgsByUser = new OrgsByUserViewModel()
{
user_id = inventory.user_id,
//mgr_emp_nbr = inventory.mgr,
org_id = inventory.org_id,
},
}).Where(e => e.metric_dt == DateTime.Today && e.org_id
==locs.Any(o=>o.org_id)) // this doesn't work
//}).Where(e => e.metric_dt == DateTime.Today && e.org_id == "SGF") //
this works
.ToList();
return result;
}
Any help you can provide would be greatly appreciated! Thank so much!

The problem is in e.org_id == locs.Any(o=>o.org_id). As I can see in your working example, your org_id is a string.
I guess what you are trying to do is .Where(e => e.metric_dt == DateTime.Today && locs.Any(o=>o.org_id == e.org_id))

Related

New class selected by LINQ query, how to transfer to another model?

I'm really not understanding this as I've only dabbled in MVC and C#. I apologize if my terminology is wrong or confusing, I will do my best to answer questions. I have a couple models like so:
public class DataSharingModels
{
public string ReferenceID { get; set; }
public NBTC NBTCGroup { get; set; }
public Contractors ContractorsGroup { get; set; }
public Coordinators CoordinatorsGroup { get; set; }
public NGO NGOGroup { get; set; }
public Public PublicGroup { get; set; }
public SelectList FA_RA_List { get; set; }
}
public class NBTC
{
public String NBTC_FA_Centroid { get; set; }
public String NBTC_FA_Bound { get; set; }
public String NBTC_RA_Centroid { get; set; }
//more properties...
}
The DataSharingModels class contains the public NBTC NBTCGroup property. It is not public List<NBTC> NBTCGroup because there will only be one produced per instance of the controller being hit.
Now in my controller, I have a LINQ statement that selects a new NBTC class:
var nbtcVals = (from ds in db.SharingPermissions
where ds.FocalRefID.ToString() == ReferenceID
&& ds.ShareGroup == "NBTC"
select new NBTC
{
NBTC_FA_Centroid = ds.CIP_FA_Centroid,
NBTC_FA_Bound = ds.CIP_FA_Boundary,
NBTC_RA_Centroid = ds.CIP_RA_Centroid,
//more properties...
});
Where I'm going wrong is I would like to add that to my DataSharingModels model. I thought the nbtcVals type would be NBTC, but it's IQueryable<##.Models.NBTC>. I understand I could do this, but it seems redundant:
DataSharingModels dsm = new DataSharingModels();
if (nbtcVals.Any())
{
foreach (var i in nbtcVals)
{
dsm.NBTCGroup.NBTC_FA_Centroid = i.NBTC_FA_Centroid;
dsm.NBTCGroup.NBTC_FA_Boundary = i.NBTC_FA_Bound;
dsm.NBTCGroup.NBTC_RA_Centroid = i.NBTC_RA_Centroid;
//more properties...
}
}
What is a more direct way to do this? There must be one. I supposed I could also return an anonymous type in the LINQ query and then assign each property in the foreach like dsm.NBTCGroup.NBTC_RA_Centroid = i.NBTC_RA_Centroid but that seems the same as the other way.
var nbtcgroup = (from ds in db.SharingPermissions
where ds.FocalRefID.ToString() == ReferenceID
&& ds.ShareGroup == "NBTC"
select new NBTC
{
NBTC_FA_Centroid = ds.CIP_FA_Centroid,
NBTC_FA_Bound = ds.CIP_FA_Boundary,
NBTC_RA_Centroid = ds.CIP_RA_Centroid,
//more properties...
})
.OrderByDescending(n => n.Id) // or some other property that could identify sorting
.FirstOrDefault();
This one has a translation to SQL (LIMIT or TOP depending on backend).

How to convert data from two tables get from Linq query to List witch can be populated in wpf form

I don't know how to convert LINQ query to List type of Owner with data from Transport table and pass it to WPF form (using MVVM)
DB structure :
Owner has many cars, so I described relation like this:
public partial class Transport
{
public Transport()
{
TransportOwners = new List<TransportOwner>();
}
[Key]
public int TransportID { get; set; }
public string PlateNo { get; set; }
public string Brand { get; set; }
public string Model { get; set; }
public virtual ICollection<TransportOwner> TransportOwners { get; set; }
}
public partial class Owner
{
[Key]
public int OwnerID { get; set; }
public int TransportID { get; set; }
[ForeignKey("TransportID")]
public virtual Transport Transport { get; set; }
[NotMapped]
public string PlateNo { get; set; }
[NotMapped]
public string Brand { get; set; }
[NotMapped]
public string Model { get; set; }
}
In ViewModel I created list type of Owner :
private List<Owner> _haveList;
public List<Owner> HaveList
{
get { return _haveList; }
set
{
if (value != _haveList)
{
_haveList = value;
RaisePropertiesChanged("HaveList");
}
}
}
Now I am trying to get the data :
using (var dbContext = new DataModelContext())
{
var query = dbContext.Owners.AsQueryable();
query = query.Where(o => o.OwnerId.Equal(OwnerParameter));
query = query.Select(t => new
{
Model = t.Transport.Model,
Brand = t.Transport.Brand,
PlateNo = t.Transport.PlateNo
}).ToList();
// Here I see data I need (list of Transport by Owner)
HaveList = query;
'System.Collections.Generic.List<<anonymous type: ... >>' to 'System.Collections.Generic.List<DataModels.Owner>'
In Linq-to-Entities you can only project to an anonymous type or a regular class. You can't project to an existing entity type
var result = (from o in query
where o.OwnerID==OwnerParameter
select new OwnerModel
{
Model=o.Transport.Model,
Brand=o.Transport.Brand
}).ToList();
1 - You should try to use a named object
HaveList= query.Select(t => new OwnerModel
{
Model = t.Transport.Model,
Brand = t.Transport.Brand,
PlateNo = t.Transport.PlateNo
}).ToList();
2 - Your query object is created as IQuerible, then you try to assign it as a List
query = query should not work I think.
Note that OwnerModel should fire INotificationEvent when one of the property is modified :)
private List<OwnerModel> _haveList;
public List<OwnerModel> HaveList
{
get { return _haveList; }
set
{
if (value != _haveList)
{
_haveList = value;
RaisePropertiesChanged("HaveList");
}
}
}
Finally I have what I need, thank You for Your help
List<Owner> list = DBContext.Owners.Where(to => to.OwnerID == ownerParameter).ToList();
HaveList = list.Select(t => new Owner()
{
Model = t.Transport.Model,
Brand = t.Transport.Brand,
PlateNo = t.Transport.PlateNo
}).ToList();

Data from model not passing to view

I have some code that is functioning oddly and was wondering if anyone else hase come across this issue.
I have a view model that collects data from a database via a stored procedure and a vb object (no I do not know vb this is legacy)
When I execute the program the data is collected as expected via the controller. When I debug it I can see all of my parameters populating with information. However when it comes to the view it says that the parameters are null. I have included my code
Models:
public class PersonIncomeViewModel
{
public string IncomeTypeDesc { get; set; }
public string IncomeDesc { get; set; }
public string Income { get; set; }
}
public class PersonIncomeListViewModel
{
public int? PersonId { get; set; }
public List<PersonIncomeListItem> Incomes { get; set; }
public PersonIncomeListViewModel()
{
Incomes = new List<PersonIncomeListItem>();
}
}
public class PersonLookupViewModel : Queue.QueueViewModel
{
public int Action { get; set; }
public bool ShowAdvancedFilters { get; set; }
//Person Search Variables
[Display(Name = #"Search")]
public string SpecialSearch { get; set; }
[Display(Name = #"Person Id")]
public int? PersonId { get; set; }
[Display(Name = #"Full Name")]
public string FullName { get; set; }
[Display(Name = #"SSN")]
public string SSN { get; set; }
public string AddressStatus { get; set; }
public string EmploymentStatus { get; set; }
public PersonIncomeViewModel Income { get; set; }
public List<PersonIncomeListItem> Incomes { get; set; }
public PersonLookupViewModel()
{
Income = new PersonIncomeViewModel();
Incomes = new List<PersonIncomeListItem>();
}
}
Controller:
public ActionResult _Income(int id)
{
var vm = new PersonLookupViewModel();
var personManager = new dtPerson_v10_r1.Manager( ref mobjSecurity);
//var person = personManager.GetPersonObject((int)id, vIncludeIncomes: true);
var person = personManager.GetPersonObject(id, vIncludeIncomes: true);
var look = JsonConvert.SerializeObject(person.Incomes);
foreach (dtPerson_v10_r1.Income income in person.Incomes)
{
if (income.IncomeType_ID == 0)
{
var item = new PersonIncomeListItem
{
IncomeTypeDesc = "Unknown",
IncomeDesc = income.IncomeDesc,
Income = mobjFormat.FormatObjectToCurrencyString(income.Income)
};
vm.Incomes.Add(item);
}
if (income.IncomeType_ID == 1)
{
var item = new PersonIncomeListItem
{
IncomeTypeDesc = "Alimony",
IncomeDesc = income.IncomeDesc,
Income = mobjFormat.FormatObjectToCurrencyString(income.Income)
};
vm.Incomes.Add(item);
}
if (income.IncomeType_ID == 2)
{
var item = new PersonIncomeListItem
{
IncomeTypeDesc = "Child Support",
IncomeDesc = income.IncomeDesc,
Income = mobjFormat.FormatObjectToCurrencyString(income.Income)
};
vm.Incomes.Add(item);
}
}
return PartialView(vm);
}
View:
#using dtDataTools_v10_r1
#using ds_iDMS.Models.Person
#model ds_iDMS.Models.Person.PersonLookupViewModel
#{
var format = new dtDataTools_v10_r1.CustomFormat();
var newInitials = (Model.Income.IncomeTypeDesc.First().ToString() + Model.Income.IncomeDesc.First().ToString() + Model.Income.Income.First().ToString()).ToUpper();
}
using (Html.DSResponsiveRow(numberOfInputs: ExtensionMethods.NumberOfInputs.TwoInputs))
{
using (Html.DSCard(ExtensionMethods.Icon.CustomText, iconInitials: newInitials, color: ExtensionMethods.Colors.PrimaryBlue))
{
<div>#Model.Income.IncomeTypeDesc</div>
<div>#Model.Income.IncomeDesc</div>
<div>#Model.Income.Income</div>
}
}
There are some extensions that we have built but they are irrelevant to the issue
The line that errors out is this one:
var newInitials = (Model.Income.IncomeTypeDesc.First().ToString() + Model.Income.IncomeDesc.First().ToString() + Model.Income.Income.First().ToString()).ToUpper();
Which drives all of the extension methods on the view and as I run the debugger over it all of the parameters read null, however like I said when I run the debugger and check them in the controller they are populated properly.
Sorry about the long post but I wanted to ensure all the detail was there
This is how to pass the Object model to your Partial View
return PartialView("YourViewName", vm);
or using the Views path
return PartialView("~/YourView.cshtml", vm);
EDIT
Try starting your Action Method like this
var vm= new Person();
vm.PersonLookupViewModel = new PersonLookupViewModel();
Problem solved I had issues with some of my vb objects and had the vb person take a look at them and she fixed them.
Thank you for all the help
EDIT
What had to happen is the vb object had to be re-written and my logic was just fine as it was in the beginning. I marked the one response to my question as the answer because had it been in true MVC without vb objects attached to it, that would have worked perfectly

MongoDB Unable to determine the serialization information for the expression error

My data is having following structure
public enum ParamType
{
Integer=1,
String=2,
Boolean=3,
Double=4
}
public class Gateway
{
public int _id { get; set; }
public string SerialNumber { get; set; }
public List<Device> Devices { get; set; }
}
public class Device
{
public string DeviceName { get; set; }
public List<Parameter> Parameters { get; set; }
}
public class Parameter
{
public string ParamName { get; set; }
public ParamType ParamType { get; set; }
public string Value { get; set; }
}
I filled 10 document objects of Gateway in a MongoDB database.
Now I want to query all those gateways which contains a device having Parameter with ParamName as "Target Temperature" and whose Value > 15.
I created following queries
var parameterQuery = Query.And(Query<Parameter>.EQ(p => p.ParamName, "Target Temperature"), Query<Parameter>.GT(p => int.Parse(p.Value), 15));
var deviceQuery = Query<Device>.ElemMatch(d => d.Parameters, builder => parameterQuery);
var finalQuery = Query<Gateway>.ElemMatch(g => g.Devices, builder => deviceQuery);
But when I run this, it is giving an exception
Unable to determine the serialization information for the expression: (Parameter p) => Int32.Parse(p.Value)
Please suggest where I am wrong.
As the error suggests, you can't use Int32.Parse inside your query. This lambda expression is used to get out the name of the property and it doesn't understand what Int32.Parse is.
If you are querying a string, you need to use a string value for comparison:
var parameterQuery = Query.And(Query<Parameter>.EQ(p => p.ParamName, "Target Temperature"), Query<Parameter>.GT(p => p.Value, "15"));
However, that's probably not what you want to do since you're using GT. To be treated as a number for this comparison you need the value to actually be an int in mongo, so you would need to change the type of your property:
public class Parameter
{
public string ParamName { get; set; }
public ParamType ParamType { get; set; }
public int Value { get; set; }
}
var parameterQuery = Query.And(Query<Parameter>.EQ(p => p.ParamName, "Target Temperature"), Query<Parameter>.GT(p => p.Value, 15));
Summary
I ran into this when I was modifying a list. It appears that Linq First/FirstOrDefault was not handled well by MongoDB for me. I changed to be an array index var update = Builders<Movie>.Update.Set(movie => movie.Movies[0].MovieName, "Star Wars: A New Hope"); Note: This is in Asp.Net 5 using MongoDB.Driver 2.2.0.
Full Example
public static void TypedUpdateExample() {
var client = new MongoClient("mongodb://localhost:27017");
var database = client.GetDatabase("test");
var collection = database.GetCollection<Movie>("samples");
//Create some sample data
var movies = new Movie {
Name = "TJ",
Movies = new List<MovieData>
{
new MovieData {
MovieName = "Star Wars: The force awakens"
}
}
};
collection.InsertOne(movies);
//create a filter to retreive the sample data
var filter = Builders<Movie>.Filter.Eq("_id", movies.Id);
//var update = Builders<Movie>.Update.Set("name", "A Different Name");
//TODO:LP:TSTUDE:Check for empty movies
var update = Builders<Movie>.Update.Set(movie => movie.Movies[0].MovieName, "Star Wars: A New Hope");
collection.UpdateOne(filter, update);
}
public class Movie {
[BsonId]
public ObjectId Id { get; set; }
public string Name { get; set; }
public List<MovieData> Movies { get; set; }
}
public class MovieData {
[BsonId]
public ObjectId Id { get; set; }
public string MovieName { get; set; }
}

MVC3 linq joins

As a novice am trying my hands on MVC3,razor, EF I have Three connected Tables that I want to produce a view from it. In a simpleton's brief the following are about the tables
PJUsers - ID, memUID(this unique Id from membership),FirstName,LastName
PJAwards - user nominates another user for an award, this links with awardtypesID as foreign key ( awardId,bool:awardok)
PJAwartypes - (awardtypeID, awardName)
The query in the controller is like this
var lists =
from tl in db.PJawards
join u in db.PJUsers on tl.nomineeId equals u.ID into tl_u
join i in db.PJUsers on tl.nominatorId equals i.MemUID into tl_i
where tl.awardOk
orderby tl.awardDated ascending
from u in tl_u.DefaultIfEmpty()
from i in tl_i.DefaultIfEmpty()
select new
{
Status = tl.awardOk,
nomineeFname = u.FirstName,
nomineeLname = u.LastName,
award = tl.PJawards.awardName,
Dated = tl.awardDated,
nominatorFname = i.FirstName,
nominatorLname = i.LastName,
nomineeCountry = u.Citizen,
nomineeResidence = u.Residence,
awardtypeId = tl.ID
};
somewhere i read that i have to construct a model class similar to the query in the controller
{
public class AwardUserInfo
{
public AwardUserInfo() { }
public bool Status { get; set; }
public string nomineeFname { get; set; }
public string nomineeLname { get; set; }
public string award { get; set; }
public string Dated { get; set; }
public string nominatorFname { get; set; }
public string nominatorLname { get; set; }
public string nomineeCountry { get; set; }
public string nomineeResidence { get; set; }
public int awardtypeId { get; set; }
}
}
Please I learn by examples so to be able to help me assume I don't know anything
somewhere i read that i have to construct a model class similar to the query in the controller
Try this.
I guess your ef-model is similar to
So You can create a ViewModel class
public class PJAwardsViewModel
{
public int Id { get; set; }
public string NominatorFName { get; set; }
public string NomineeFname { get; set; }
public string AwardName { get; set; }
public bool IsAwarded { get; set; }
}
It will be also good if You add some service class
public class PJAwardsService
{
public static List<PJAwards> GetAll()
{
using (var context = new YourDBEntities())
{
return context.PJAwards
.Include(x => x.PJUsers)
.Include(x => x.PJUsers1)
.Include(x => x.PJAwartypes).ToList();
}
}
}
(Don't forget to write using System.Data.Entity; )
Then You can add a ViewModelHelper class
public class PJAwardsViewModelHelper
{
public static PJAwardsViewModel PopulatePJAwardsViewModel(PJAwards pjaward)
{
return new PJAwardsViewModel
{
Id = pjaward.Id,
NominatorFName = pjaward.PJUsers.FirstName,
NomineeFname = pjaward.PJUsers1.FirstName,
AwardName = pjaward.PJAwartypes.AwardName,
IsAwarded = pjaward.IsAwarded
};
}
public static List<PJAwardsViewModel> PopulatePJAwardsViewModelList(List<PJAwards> pjawardsList)
{
return pjawardsList.Select(x => PopulatePJAwardsViewModel(x)).ToList();
}
}
At the end Your controller index method will look like this
public ActionResult Index()
{
var pjawards = PJAwardsViewModelHelper.PopulatePJAwardsViewModelList(PJAwardsService.GetAll().ToList());
return View(pjawards);
}
The only thing You should do is add a view (build the project before). Choose PJAwardsViewModel as a Model class and List as a scaffold template.
Enjoy it.
Here is a step by step guide by Steven Sanderson on how to use Asp.net MVC3, EF Code First with MVCScaffolding (powershell automation).
http://blog.stevensanderson.com/2011/01/13/scaffold-your-aspnet-mvc-3-project-with-the-mvcscaffolding-package/
It is a multipart blog post takes you through the exciting journey of MVC3.
All the best.

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