I have a linq query that returns a schedule for a doctor in a specific date, that works ok:
var scheduledList = db_hms.Scheduled
.Include("Natural_Person")
.Include("Type_Schedule")
.Where(s => s.id_medical_doctor == idMedic && s.date_time >= date && s.date_time <= EndDate).OrderBy(s => s.date_time).ToList();
but now, i have 2 extra fields i need to filter, so i need a way to evaluate if applay the filter or not, i was thinking in remove rhe orderby and the toList()and do somthing like:
if (idTipoConsulta != -1)
{
scheduledList.Where(m => m.id_ps_schedule == idTipoConsulta);
}
if (idEspecialidad != -1)
{
scheduledList.Where(m => m.id_specialty == idTipoConsulta);
}
return scheduledList.OrderBy(s => s.date_time).ToList();
but it does not seem to work.
Calling Where doesn't affect the object you call it on - it returns a new query with the filter applied. So you want to use the return value appropriately. For example:
if (idTipoConsulta != -1)
{
scheduledList = scheduledList.Where(m => m.id_ps_schedule == idTipoConsulta);
}
// etc
Related
i am fetching all the records from the database with the help of this query organization wise. they become about 30-40 records
List<PagesRef> paages = (from pagess in pagerepository.GetAllPages()
join pagesref in pagerepository.GetAllPageRef()
on pagess.int_PageId equals pagesref.int_PageId
where (pagess.int_PostStatusId != 3 && pagess.int_OrganizationId == Authorization.OrganizationID)
&& pagesref.int_PageRefId == pagesref.Pages.PagesRefs.FirstOrDefault(m => m.int_PageId == pagess.int_PageId && m.bit_Active == true && (m.vcr_PageTitle != null && m.vcr_PageTitle != "")).int_PageRefId
select pagesref).ToList();
next the next step what i want to do is to loop through the above list as linq to object query without going to the database to generate 3 level hierarchical record. can some one give me some insight or idea how can i do it?
edit
var parentrecord = paages.Where(n => n.Pages.int_PageParent == 0).OrderBy(m => m.Pages.int_SortOrder == null).OrderBy(m => m.int_PageId);
foreach (var secondlevel in parentrecord) // if parentrecord found
{
var seclevel = paages.Where(m => m.Pages.int_PageParent == secondlevel.Pages.int_PageId).OrderBy(m => m.Pages.int_SortOrder == null).OrderBy(m => m.Pages.int_SortOrder);
secondlevel.vcr_PageTitle = "parent";
pagesreff.Add(secondlevel); // if parentrecord found then loop and add in there
foreach (var thdlevel in seclevel)
{
var thirdlevel = paages.Where(m => m.Pages.int_PageParent == thdlevel.Pages.int_PageId).OrderBy(m => m.Pages.int_SortOrder == null).OrderBy(m => m.int_PageId).OrderBy(m => m.Pages.int_SortOrder);
thdlevel.vcr_PageTitle = "child";
pagesreff.Add(thdlevel); // if parentrecord child found then loop and add in there
foreach (var thd in thirdlevel)
{
thd.vcr_PageTitle = "subchild";
pagesreff.Add(thd); // if parentrecord child found then loop and add in there
}
}
}
After ToList(); linq-to-sql go to database and get rows. After that, you have collection of objects and can do what you want with linq to objects:
var filteredList = paages.Where(someFilter);
there will be no new sql requests.
Update
Your problem is that you filter in navigation property, so you should load your navigation property with your first query. I'm not sure (linq-to-sql was many years ago:)), but this should help you (I assume that m.Pages is of type Page):
List<PagesRef> paages = (from pagess in pagerepository.GetAllPages()
join pagesref in pagerepository.GetAllPageRef()
on pagess.int_PageId equals pagesref.int_PageId
where (pagess.int_PostStatusId != 3 && pagess.int_OrganizationId == Authorization.OrganizationID)
&& pagesref.int_PageRefId == pagesref.Pages.PagesRefs.FirstOrDefault(m => m.int_PageId == pagess.int_PageId && m.bit_Active == true && (m.vcr_PageTitle != null && m.vcr_PageTitle != "")).int_PageRefId
select pagesref).AssociateWith<Page>.ToList();
Given the query below
public TrainingListViewModel(List<int> employeeIdList)
{
this.EmployeeOtherLeaveItemList =
CacheObjects.AllEmployeeOtherLeaves
.Where(x => x.OtherLeaveDate >= Utility.GetToday() &&
x.CancelDate.HasValue == false &&
x.OtherLeaveId == Constants.TrainingId)
.OrderBy(x => x.OtherLeaveDate)
.Select(x => new EmployeeOtherLeaveItem
{
EmployeeOtherLeave = x,
SelectedFlag = false
}).ToList();
}
I want to put in the employeeIdList into the query.
I want to retrieve all of the x.OtherLeaveDate values where the same x.OtherLeaveDate exists for each join where x.EmployeeId = (int employeeId in employeeIdList)
For example if there are EmployeeIds 1, 2, 3 in employeeIdList and in the CacheObjects.AllEmployeeOtherLeaves collection there is a date 1/1/2001 for all 3 employees, then retreive that date.
If I read you well it should be something like
var grp = this.EmployeeOtherLeaveItemList =
CacheObjects.AllEmployeeOtherLeaves
.Where(x => x.OtherLeaveDate >= Utility.GetToday()
&& x.CancelDate.HasValue == false
&& x.OtherLeaveId == Constants.TrainingId
&& employeeIdList.Contains(x.EmployeeId)) // courtesy #IronMan84
.GroupBy(x => x.OtherLeaveDate);
if (grp.Count() == 1)
{
var result = g.First().Select(x => new EmployeeOtherLeaveItem
{
EmployeeOtherLeave = x,
SelectedFlag = false
})
}
First the data is grouped by OtherLeaveDate. If the grouping results in exactly one group, the first (and only) IGrouping instance is taken (which is a list of Leave objects) and its content is projected to EmployeeOtherLeaveItems.
To the where statement add "&& employeeIdList.Contains(x.EmployeeId)"
I need to thank #IronMan84 and #GertArnold for helping me along, and I will have to admonish myself for not being clearer in the question. This is the answer I came up with. No doubt it can be improved but given no one has responded to say why I will now tick this answer.
var numberOfEmployees = employeeIdList.Count;
var grp = CacheObjects.AllEmployeeOtherLeaves.Where(
x =>
x.OtherLeaveDate >= Utility.GetToday()
&& x.CancelDate.HasValue == false
&& x.OtherLeaveId == Constants.TrainingId
&& employeeIdList.Contains(x.EmployeeId))
.GroupBy(x => x.OtherLeaveDate)
.Select(x => new { NumberOf = x.Count(), Item = x });
var list =
grp.Where(item => item.NumberOf == numberOfEmployees).Select(item => item.Item.Key).ToList();
I’m trying to retrieve data from an entity and populate a viewModel property like this:
viewModel.Enrollments = db.Enrollments.Where(b => b.classDays == "Monday") && (db.Enrollments.Where(b => b.CourseID == courseID);
but I get a operator && cannot be applied to operands of type System.Linq.IQerable<> error. Can you help with a way to find all Monday class with the same ID?
I tried this: viewModel.Enrollments = db.Enrollments.Where(b => b.classDays == "Monday") but I get all Mondays courses but I want to limit them to a specific courseID.
Please help!
You need to examine your parentheses. This code won't even compile:
viewModel.Enrollments = db.Enrollments.Where(b => b.classDays == "Monday")
&& (db.Enrollments.Where(b => b.CourseID == courseID);
In that code you're trying to use && between two calls to .Where(), which return an IQueryable. You probably mean to use && within the .Where() clause:
viewModel.Enrollments = db.Enrollments.Where(b => (b.classDays == "Monday")
&& (b.CourseID == courseID));
Or perhaps append a second .Where() clause:
viewModel.Enrollments = db.Enrollments.Where(b => b.classDays == "Monday")
.Where(b => b.CourseID == courseID);
Note that .Where() can be chained indefinitely, essentially resulting in applying each clause in turn in an AND fashion in the resulting query.
&& Operator should be used with conditions inside where NOT with sets of enrollments (in your case)
Try This:
viewModel.Enrollments = db.Enrollments.Where(b => (b.classDays == "Monday") && (b.CourseID == courseID));
I'm trying to build a query using LINQ for EF to filter results based on some basic logic. For some reason, even with the following Where() functions being executed and setting the right parameters, all data is being returned instead of the filtered results from Where().
I have run debug to make sure that my if() statements are indeed allowing the Where() to run when appropriate, and it is.
What am I missing?
var dbReports = db.SubmitReports;
if (Referee != String.Empty)
dbReports.Where(u => (u.Refree == Referee || u.Ar1Official == Referee || u.Ar2Official == Referee || u.FourthOfficial == Referee));
if (TeamName != String.Empty)
dbReports.Where(u => (u.HomeTeam == TeamName || u.VisitingTeam == TeamName));
if (PlayedOnStart != DateTime.MinValue && PlayedOnEnd != DateTime.MinValue)
dbReports.Where(u => (u.PlayedOn >= PlayedOnStart && u.PlayedOn <= PlayedOnEnd));
if (StateAssociation != String.Empty)
dbReports.Where(u => (u.StateAssociation == StateAssociation || u.StateAssociation2 == StateAssociation));
if (Division != String.Empty)
dbReports.Where(u => u.Division == Division);
if (ProfessionalLeague != String.Empty)
dbReports.Where(u => u.ProfessionalLeague == ProfessionalLeague);
if (AgeGroup != String.Empty)
dbReports.Where(u => u.AgeGroup == AgeGroup);
return dbReports.ToList();
Where doesn't modify the existing query - it creates a new query. You need to assign the result of the call to Where to something otherwise the result is simply discarded. Try this:
IQueryable<Report> dbReports = db.SubmitReports;
if (...)
{
dbReports = dbReports.Where(...);
}
You never use the return value of the Where method. Where does not modify the IEnumerable it is apply on but returns a Linq expression that will create a modify IEnumerable when executed (i.e when ToList is called).
Basically I want to write a linq query to order the number of days they were present. But I have got these six time filters- Today,Yesterday,current month,previous month,current year,previous year.So now I have this queries which I have simplified but before these queries below, I actually order these employees on different aspects and after ordering it as you can see I assign rank and then at the same time find out his count(which may or may not be used to rank them later)-
var result=datacontext.Employee(c=>c.Company.Id==companyId).Select((k, index) => new EmployeeDTO()
{
EmployeeId=k.Employee.Id,
CompanyId=Employee.Company.Id
PresentCount=(from e in employeeAttendance
where d.RecNum == k.recnum
&& d.date_present.Year == DateTime.Today.Year
&& d.date_present.Month == DateTime.Today.Month
&& d.date_present.Day == DateTime.Today.Day
select d).Count()
}
So now when the filter is say previous year I have -
var result=datacontext.Employee(c=>c.Company.Id==companyId).Select((k, index) => new EmployeeDTO()
{
Position=
EmployeeId=k.Employee.Id,
CompanyId=Employee.Company.Id
PresentCount=(from e in employeeAttendance
where d.RecNum == k.recnum
&& d.date_present.Year == (DateTime.Today.Year-1)
}
and if have it on Current Month I have -
var result=datacontext.Employee(c=>c.Company.Id==companyId).Select((k, index) => new EmployeeDTO()
{
EmployeeId=k.Employee.Id,
CompanyId=Employee.Company.Id
PresentCount=(from e in employeeAttendance
where d.RecNum == k.recnum
&& d.date_present.Month == DateTime.Today.Month
&& d.date_present.Year == DateTime.Today.Year
}
I basically want to combine all these in one query with basically having like a dynamic clause for finding out the present count ?
Just create a simple wrapper. Eg:
IQueryable<EmployeeDTO> GetEmployeeCount(Expression<Func<DateTime, bool>> pred)
{
var result=datacontext.Employee(c=>c.Company.Id==companyId).
Select((k, index) => new EmployeeDTO()
{
EmployeeId=k.Employee.Id,
CompanyId=Employee.Company.Id,
PresentCount=(from e in employeeAttendance
where d.RecNum == k.recnum && pred(d.date_present)
select d).Count()
});
return result;
}
Usage:
var r = GetEmployeeCount(d => d.Year == (DateTime.Today.Year-1));
var r = GetEmployeeCount(
d => d.Month == DateTime.Today.Month && d.Year == DateTime.Today.Year);