Convert query expression to lambda in LINQPad4 - linq

While coding I had came across a LINQ query that I was able to accomplish in query syntax but not in lamda syntax. While this works fine in the application, I wanted to learn the query syntax for what I was trying to do.
Essentially, I have a database with views, CO_Leather_V and CO_LeatherSizeColor_V. I also have two classes, CuttingOrder and CuttingOrderDetail. CuttingOrderDetail contains entirely string,int and float properties. The CuttingOrder Class contains 2 string properties and a List of CuttingOrderDetails.
public class CuttingOrder
{
public string cuttingOrderNo { get; set; }
public string reserveSalesOrderNo { get; set; }
public List<CuttingOrderDetail> details { get; set; }
}
public class CuttingOrderDetail
{
public string cuttingOrderNo { get; set; }
public string reserveSalesOrderNo { get; set; }
public string itemCode { get; set; }
public string material { get; set; }
public string color { get; set; }
public string size { get; set; }
public int qty { get; set; }
public float squareFeet { get; set; }
public float squareFeetUsed { get; set; }
}
The query expression I used to get a list of all CuttingOrders with a given SalesOrder was
cos = (from l in db.CO_Leather_Vs
where l.orderNo == Globals.orderNo
select new Globals.CuttingOrder
{
cuttingOrderNo = "NOT SET",
reserveSalesOrderNo = "FAKE_SO_NO",
details = (
from d in db.CO_LeatherSizeColor_Vs
select new Globals.CuttingOrderDetail
{
cuttingOrderNo = d.orderNo
}
).ToList()
}).ToList();
I converted this to work in LINQPad with the following query, but I can't get anything to show on the lambda pane.
void Main()
{
var p = (from l in CO_Leather_V
select new CuttingOrder
{
cuttingOrderNo = "NOT SET",
reserveSalesOrderNo = "FAKE_SO_NO",
details = (
from d in CO_LeatherSizeColor_V
select new CuttingOrderDetail
{
cuttingOrderNo = d.OrderNo
}
).ToList()
}).ToList();
p.Dump();
}
// Define other methods and classes here
public class CuttingOrder
{
public string cuttingOrderNo { get; set; }
public string reserveSalesOrderNo { get; set; }
public List<CuttingOrderDetail> details { get; set; }
}
public class CuttingOrderDetail
{
public string cuttingOrderNo { get; set; }
public string reserveSalesOrderNo { get; set; }
public string itemCode { get; set; }
public string material { get; set; }
public string color { get; set; }
public string size { get; set; }
public int qty { get; set; }
public float squareFeet { get; set; }
public float squareFeetUsed { get; set; }
}
If anyone knows how to perform the linq query in lambda form or knows why LINQPad is unable to generate the lamda form it would be greatly appreciated.

This should work:
var p = CO_Leather_V.Select(l=> new CuttingOrder
{
cuttingOrderNo = "NOT SET",
reserveSalesOrderNo = "FAKE_SO_NO",
details = CO_LeatherSizeColor_V.Select(d=>new CuttingOrderDetail {cuttingOrderNo = d.OrderNo}).ToList()
}).ToList();
However, CO_LeatherSizeColor_V does not reference l, so you're going to get everything in that table, every time. You might want something like:
details = l.LeatherSizeColor.Select(d=>new CuttingOrderDetail {cuttingOrderNo = d.OrderNo}).ToList()
for that line instead.

Related

InvalidCastException: Unable to cast object of type 'System.Collections.Generic.List to System.Collections.Generic.IEnumerable

I am trying to implementation clean architecture in netcore and I have Runtime Error
InvalidCastException: Unable to cast object of type 'System.Collections.Generic.List to System.Collections.Generic.IEnumerable
In the WebUI I have Match controller and ViewAllMatch Action like this
public async Task<IActionResult> ViewAllMatch()
{
var matches = await _mediator.Send(new GetMatchesDetail());
return View(matches);
}
In the application Layer I have A queries like this:
public class GetMatchesDetail : IRequest<IEnumerable<MatchesDetail>>
{
}
public class MatchesDetail
{
public string MatchId { get; set; }
public int MatchNumer { get; set; }
public DateTime DateMatch { get; set; }
public TimeSpan TimeMatch { get; set; }
public int MatchYear { get; set; }
public string SeasonId { get; set; }
public string Round { get; set; }
/// <summary>
/// Set value to Qualified for Qualified and Final for Final Round
/// </summary>
public string Stage { get; set; }
public string SubStage { get; set; }
public string HTeam { get; set; }
public string HTeamCode { get; set; } //For Flag get from Table Team from Foreign Key TeamName
public int HGoal { get; set; }
public int GGoal { get; set; }
public string GTeam { get; set; }
public string GTeamCode { get; set; }
public string WinNote { get; set; }
public string Stadium { get; set; }
public string Referee { get; set; }
public long Visistors { get; set; }
public string Status { get; set; }
}
public class GetMatchesHandler : IRequestHandler<GetMatchesDetail, IEnumerable<MatchesDetail>>
{
private readonly IMatchRepository _matchRepository;
public GetMatchesHandler(IMatchRepository matchRepository)
{
_matchRepository = matchRepository;
}
public async Task<IEnumerable<MatchesDetail>> Handle(GetMatchesDetail request, CancellationToken cancellationToken)
{
var matchlistview = await _matchRepository.GetMatchDetailAsync();
return matchlistview;
}
}
And the code for matchRepository to get all the match in Infastructure like this.
public async Task<IEnumerable<MatchesDetail>> GetMatchDetailAsync()
{
var matchDetailList = (from match in _context.Matches
join team1 in _context.Teams on match.HTeam equals team1.TeamName
join team2 in _context.Teams on match.GTeam equals team2.TeamName
join season in _context.Seasons on match.SeasonId equals season.SeasonId
select new
{
match.MatchId,
match.MatchNumber,
match.DateMatch,
match.TimeMatch,
match.MatchYear,
match.SeasonId,
season.SeasonName,
match.Round,
match.Stage,
match.SubStage,
match.HTeam,
HTeamCode = team1.TeamCode,
match.HGoal,
match.GGoal,
match.GTeam,
GTeamCode = team2.TeamCode,
match.WinNote,
match.Stadium,
match.Referee,
match.Visistors
});
return (IEnumerable<MatchesDetail>)await matchDetailList.ToListAsync();
}
Full code have been upload to Github at https://github.com/nguyentuananh921/Betting.git.
for more detail.
Thanks for your help.
I am so confuse about model in clean architech when i have more entities and the model I want to view in the WebUI contain many entities in domain.
Thanks for your help.
I have Modify public IEnumerable GetMatchDetailAsync() like that.
public IEnumerable<MatchesDetail> GetMatchDetailAsync()
{
#region TryOther way
var matchQuery = (from match in _context.Matches
join team1 in _context.Teams on match.HTeam equals team1.TeamName
join team2 in _context.Teams on match.GTeam equals team2.TeamName
join season in _context.Seasons on match.SeasonId equals season.SeasonId
select new
{
#region selectResult
//Remove to clear Select what I want to get.
#endregion
});
MatchesDetail matchesDetail = new MatchesDetail();
List<MatchesDetail> retList = new List<MatchesDetail>();
//IEnumerable<MatchesDetail> retList;
foreach (var item in matchQuery)
{
#region ManualMapping
matchesDetail.MatchId = item.MatchId;
//other field mapping
#endregion
retList.Add(matchesDetail);
}
#endregion
return retList;
}
And it work

how can I Select One row where max StartDate in list objects using linq

how can I Select One row json where max StartDate in list objects
using linq tolist
{"itmes":[
{"StartDate":"20190901185703","Name":"A1","Id":"1","EndDate":"20190930235959"}
,{"StartDate":"20190903181510","Name":"A2","Id":"2","EndDate":"20190909235959"}
,{"StartDate":"20190906005152","Name":"A3","Id":"3","EndDate":"20191006235959"}
,{"StartDate":"20190714181313","Name":"A4","Id":"4","EndDate":"20991231235959"}
],"Code":"0","text":"success"}
public class Query
{
public class itmes
{
public string StartDate { get; set; }
public string Name { get; set; }
public string Id { get; set; }
public string EndDate { get; set; }
}
public class RootObject
{
public List<itmes> itmes { get; set; }
public string Code { get; set; }
public string text { get; set; }
}
}
var result = JsonConvert.DeserializeObject<List<Query.RootObject>>(json);
Expected output This row tolist
{"StartDate":"20190906005152","Name":"A3","Id":"3","EndDate":"20191006235959"}
Firstly you cannot cast and object to collection so it should be Query.RootObject instead of this List<Query.RootObject> ,Secondly im not sure why did you make class inside a class you can do it independently without the query class
You classes would be
public class itmes
{
public string StartDate { get; set; }
public string Name { get; set; }
public string Id { get; set; }
public string EndDate { get; set; }
}
public class RootObject
{
public List<itmes> itmes { get; set; }
public string Code { get; set; }
public string text { get; set; }
}
var json = "{\"itmes\":[ {\"StartDate\":\"20190901185703\",\"Name\":\"A1\",\"Id\":\"1\",\"EndDate\":\"20190930235959\"} ,{\"StartDate\":\"20190903181510\",\"Name\":\"A2\",\"Id\":\"2\",\"EndDate\":\"20190909235959\"} ,{\"StartDate\":\"20190906005152\",\"Name\":\"A3\",\"Id\":\"3\",\"EndDate\":\"20191006235959\"} ,{\"StartDate\":\"20190714181313\",\"Name\":\"A4\",\"Id\":\"4\",\"EndDate\":\"20991231235959\"} ],\"Code\":\"0\",\"text\":\"success\"}";
var result = JsonConvert.DeserializeObject<RootObject>(json);
var row = result.itmes.Where(p=> p.StartDate == result.itmes.Max(q => q.StartDate)).ToList();

Max value LINQ using class

I've got this class
public class Materiale
{
public string IdMateriale { get; set; }
public string GenereMateriale { get; set; }
public string Categoria { get; set; }
public string Modello { get; set; }
public string Tipo { get; set; }
public string NumSerie { get; set; }
public int Anno { get; set; }
public string DittaCostruttrice { get; set; }
public string Note { get; set; }
public List<Controllo> Controlli = new List<Controllo>();
}
public class Controllo
{
public string IdControllo { get; set; }
public DateTime DataControllo { get; set; }
public string IdMateriale { get; set; }
public string Utente { get; set; }
public string Stato { get; set; }
public string Note { get; set; }
}
I want to query a list of "Materiale" filtering "Controlli". I need to retrieve all properties of the "Materiale" class and only one property of the "Controllo" class (the one named "Stato"). From the list "Controlli" I need the one that has the most recent "DataControllo" property.
I try this in a LINQ query but I receive an error (Max doesn't exist in the current context)
List<Materiale> m = new List<Materiale>();
List<Materiale> m2 = (from ma in m
from c in ma.Controlli
where c.DataControllo == Max(c.DataControllo)
select new
{
ma, c.Stato
}).ToList();
Can someone help me
#Christos is correct, here is my version with let in query syntax:-
List<Materiale> m2 = from m in MaterialeList
let RecentControllo = m.OrderByDescending(x => x.DataControllo)
.FirstOrDefault()
select new Materiale
{
IdMateriale = m.IdMateriale,
GenereMateriale = m.GenereMateriale,
//Similarily other properties of Materiale here
Stato = RecentControllo != null ? RecentControllo.Stato : ""
}).ToList();
I think that you need something more simple like the following one:
List<Materiale> m2 = from ma in m
let mostRecentControllo = ma.Controlli
.OrderByDescending(c=>c.DataControllo)
.FirstOrDefault()
select new
{
Materiale = ma,
Stato = mostRecentControllo != null
? mostRecentControllo.Stato : null
}).ToList();
I have supposed that each Materiale's Controlli list contains Controllo with the same IdMateriale.

Linq ORM map Object to 3 level Object

I have object like this. This include Group Question (QG), 1 group question has many Question(Q), 1 question has many answer.
public class CrmQuestionAnswer
{
public long QgId { get; set; }
public string QgName { get; set; }
public int QgMIndex { get; set; }
public int QgMdf { get; set; }
public string QgDescription { get; set; }
public long QId { get; set; }
public long QParentId { get; set; }
public string QName { get; set; }
public string QDescription { get; set; }
public int QMindex { get; set; }
public int QMdf { get; set; }
public bool IsMainQuestion { get; set; }
public bool IsTitle { get; set; }
public int QTypeId { get; set; }
public long AnswerId { get; set; }
public string AnswerName { get; set; }
public string AnswerValue { get; set; }
public int AnswerMdf { get; set; }
public int AnswerMIndex { get; set; }
public string AnswerDescription { get; set; }
public long? LinkQuestionId { get; set; }
}
I want to use Linq to map List CrmQuestionAnswer to List QuestionGroupView
public class QuestionGroupView:Title
{
public List<CrmQuestionView> Questions;
}
public class CrmQuestionView: Title
{
public long? ParentId;
public bool? IsMainQuestion;
public bool? IsTitle;
public long? LinkQuestionId;
public List<CrmAnswerView> Answers;
}
public class CrmAnswerView : Title
{
public long? LinkQuestionId;
}
Title is base class:
public class Title
{
public long Id { get; set; }
public string Name { get; set; }
public int MIndex { get; set; }
public int Mdf { get; set; }
public int Type { get; set; }
public string Description { get; set; }
}
I use this code:
public List<QuestionGroupView> GetListQuestionsAnswers(long themaId)
{
var questionAnswerDao = new CrmQuestionAnswerDao();
var questionAnswerlist = questionAnswerDao.GetByThemasId(themaId);
//map List CrmQuestionAnswer -> List QuestionGroupView: 3 level
var listquestiongroup = questionAnswerlist
.OrderBy(t => t.QgMIndex)
.ThenBy(t => t.QMindex)
.GroupBy(t => t.QgId)
.Select(GetQuestionGroup)
.ToList();
return listquestiongroup;
}
private static QuestionGroupView GetQuestionGroup(IGrouping<long, CrmQuestionAnswer> grouping)
{
var group = grouping.First();
var question = new QuestionGroupView
{
Id = group.QgId,
Name = group.QgName,
Description = group.QgDescription,
Mdf = group.QgMdf,
MIndex = group.QgMIndex,
Questions = grouping
.Select(p => new CrmQuestionView
{
Id = p.QId,
Name = p.QName,
Description = p.QDescription,
Mdf = p.QMdf,
MIndex = p.QMindex,
Type = p.QTypeId,
ParentId = p.QParentId,
IsMainQuestion = p.IsMainQuestion,
IsTitle = p.IsTitle,
Answers = grouping//**This line is wrong**
.GroupBy(g => g.QId)
.Select(GetTitle)
.ToList()
})
.ToList()
};
return question;
}
private static CrmAnswerView GetTitle(IGrouping<long, CrmQuestionAnswer> grouping)
{
var group = grouping.First();
var answer = new CrmAnswerView
{
Id = group.AnswerId,
Name = group.AnswerName,
Description = group.AnswerDescription,
MIndex = group.AnswerMIndex,
Mdf = group.AnswerMdf,
Type = group.QTypeId,
LinkQuestionId = group.LinkQuestionId,
};
return answer;
}
This is data get from server Data
My code gets right Group question (2 group) with right List question, but it gets wrong list answer from data.
Can some help me ?
Best regards

Joining in LINQ to select a sublist within a list

I have two classes as follows:
public class HRM_SERVICE_PERD_BNFT_DTLModel
{
public string SRVC_PERD_BNFT_CODE { get; set; }
public string RTR_BNFT_CODE { get; set; }
public string RTR_BNFT_NAME { get; set; }
public string RTR_BNFT_CALC_MODE { get; set; }
public string SAL_HEAD_CODE { get; set; }
public string SAL_HEAD_NAME { get; set; }
public string RTR_BNFT_IN_PERCENT { get; set; }
public string RTR_BNFT_AMOUNT { get; set; }
public string RTR_BNFT_INACTV_DATE { get; set; }
public short? RTR_BNFT_SLNO { get; set; }
}
public class HRM_RETIREMENT_BENEFITModel : BaseModel
{
public string RTR_BNFT_CODE { get; set; }
public string RTR_BNFT_NAME { get; set; }
public string RTR_BNFT_SRTNM { get; set; }
public string RTR_BNFT_REM { get; set; }
public short? RTR_BNFT_SLNO { get; set; }
}
Now I want to select data from the first model for a specific 'SRVC_PERD_BNFT_CODE', then I need to select the 'RTR_BNFT_NAME' from the second table for all the filtered data along with some other value from the first model. I'm trying kind of joining, but not getting the name. It's showing system.collection.string instead of value.
Here is what I'm trying so far:
public List<HRM_SERVICE_PERD_BNFT_DTLModel> GetBenefitData(string mstcode)
{
var model2 = DataContext.HRM_SERVICE_PERD_BNFT_DTL.AsEnumerable().Where(m => m.SRVC_PERD_BNFT_CODE == mstcode).Select(s=>s).ToList();
var model = DataContext.HRM_SERVICE_PERD_BNFT_DTL.AsEnumerable().Where(m => m.SRVC_PERD_BNFT_CODE == mstcode)
.Select(s => new HRM_SERVICE_PERD_BNFT_DTLModel
{
RTR_BNFT_CODE = s.RTR_BNFT_CODE,
RTR_BNFT_SLNO = s.RTR_BNFT_SLNO,
RTR_BNFT_CALC_MODE = s.RTR_BNFT_CALC_MODE,
RTR_BNFT_AMOUNT = (s.RTR_BNFT_AMOUNT).ToString(),
RTR_BNFT_NAME = (from x in model2
join c in DataContext.HRM_RETIREMENT_BENEFIT on x.RTR_BNFT_CODE equals c.RTR_BNFT_CODE into p
from b in p.AsEnumerable()
select b.RTR_BNFT_NAME).ToList().ToString(),
RTR_BNFT_IN_PERCENT = (s.RTR_BNFT_IN_PERCENT).ToString()
}).ToList();
return model;
}
What I'm doing wrong? Please help.
Following is suspicious.
.ToList().ToString()
Remove the ToString part and replace it with something like FirstorDefault, then it should work.
Reason for getting something like System.Collection.String is that List<T>.ToString() is usually typename until it is overridden in some way.
Following minimal snipped produce System.Collections.Generic.List1[System.String]`
List<String> list = new List<String>();
var str = list.ToString();
Console.WriteLine(str); //System.Collections.Generic.List`1 [ System.String ]

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