i've a action SearchPost. in the get action:
ViewBag.cities = db.cities.ToList();
ViewBag.areas = db.areas.ToList();
IEnumerable<SelectListItem> Months =pm.GetMyMonthList().Select(a => new
SelectListItem {
Value = a.Value,
Text = a.Text
}).ToList();
ViewBag.monthList = Months;
IEnumerable<SelectListItem> rentTypes = pm
.GetRentType()
.Select(a => new SelectListItem
{
Value = a.Value,
Text = a.Text
})
.ToList();
ViewBag.typeList = rentTypes;
return View(db.posts.Include("user").ToList());
in the view page
#Html.DropDownList("City",new SelectList(ViewBag.cities as
System.Collections.IEnumerable, "city_id", "name"),
"Select City", new { id = "ddlCars" })
#Html.DropDownList("Area", new SelectList(Enumerable.Empty<SelectListItem>(),
"area_id", "name"),
"Select Area", new { id = "ddlModels" })
#Html.DropDownList("rent_type", new SelectList(ViewBag.typeList as
System.Collections.IEnumerable, "Value", "Text"), "Select Category")
#Html.DropDownList("month", new SelectList(ViewBag.monthList as
System.Collections.IEnumerable, "Value", "Text"), "Select Month")
in my Post action:
IList<post> p = db.posts.Include("user").ToList();
string Area = Request.Form["Area"];
string City = Request.Form["City"];
if (City != "Select City" && City != null && City !="")
{
int c_id = Convert.ToInt32(City);
city c = db.cities.Single(s => s.city_id == c_id);
ci = c.name;
}
if (Area != "Select Area" && Area != null && Area !="")
{
int a_id = Convert.ToInt32(Area);
area a = db.areas.Single(x => x.area_id == a_id);
ar = a.name;
}
string rent_type = Request.Form["rent_type"];
string month = Request.Form["month"];
if (rent_type != null && rent_type != "")
{
if ((p != null) && (p.Any()))
{
p = p.Where(a => a.rent_type == rent_type).ToList();
}
}
if (month!= null && month != "")
{
if ((p != null) && (p.Any()))
{
p = p.Where(a => a.rent_month == month).ToList();
}
}
return View(p);
here i've select all posts from my database first. then i want to filter it by city,area, month and rent_type. City and area are cascade dropdownlist.when i select city and area it filter records correctly. but if i select only city it gives error: Sequence contains no elements at the line:
area a = db.areas.Single(x => x.area_id == a_id);
and when i try to filter by only month or rent_type it didn't filter records and always give no records. in which part of code should i change for solve those two problems... thanks in advance...
Related
var result = (from p in db.push_notifications
join nu in db.notification_recievers on p.id equals nu.push_notification_id
join nt in db.notification_types on p.notification_type_id equals nt.id
where (p.id == pushNotificationId && p.send_criteria == criteria && nu.delete_flag == false && p.delete_flag == false && nt.delete_flag == false)
select new NotificationList
{
conferenceId = p.conference_id,
pushNotificationId = p.id,
notificationId = nt.id,
notificationType = nt.notification_type,
nottificationDate = p.created_dt_tm,
criteria = (int)p.send_criteria,
notificationMessage = p.notification_msg,
userEmail=null,
userInterests = **getInterestNamesByPushNotificationId(p.id)**,
userEvents=null
}).Distinct();
public string getInterestNamesByPushNotificationId(int id)
{
string interests = string.Empty;
var query = from i in db.interests
join pn in db.notification_recievers
on i.id equals pn.interest_id
where pn.push_notification_id == id && pn.delete_flag == false
select new
{
name = i.name
};
foreach (var intr in query.Distinct())
{
if (interests == "")
{
interests = intr.name;
}
else
{
interests = interests + ", " + intr.name;
}
}
return interests;
}
this is throwing me error
LINQ to Entities does not recognize the method 'System.String
getInterestNamesBy PushNotification(Int32)' method, and this method
cannot be translated into a store expression.
The Entity Framework is trying to execute your LINQ clause on the SQL side, obviously there is no equivalent to 'getInterestNamesBy PushNotification(Int32)' from a SQL perspective.
You need to force your select to an Enumerable and then reselect your object using the desired method.
Not ideal but something like this should work - (not tested this so be nice).
var result = (from p in db.push_notifications
join nu in db.notification_recievers on p.id equals nu.push_notification_id
join nt in db.notification_types on p.notification_type_id equals nt.id
where (p.id == pushNotificationId && p.send_criteria == criteria && nu.delete_flag == false && p.delete_flag == false && nt.delete_flag == false)
select new { p=p, nu = nu, nt = nt }).AsEnumerable().Select( x => new NotificationList()
{
conferenceId = x.p.conference_id,
pushNotificationId = x.p.id,
notificationId = x.nt.id,
notificationType = x.nt.notification_type,
nottificationDate = x.p.created_dt_tm,
criteria = (int)x.p.send_criteria,
notificationMessage = x.p.notification_msg,
userEmail=null,
userInterests = getInterestNamesByPushNotificationId(x.p.id),
userEvents=null
}).Distinct();
i have done it this way
In my model
using (NotificationService nService = new NotificationService())
{
modelView = nService.DetailsOfNotifications(pushNotificationId, criteriaId).Select(x => new NotificationViewModelUI(x.conferenceId, x.pushNotificationId, x.notificationId, x.notificationType, x.nottificationDate, x.criteria, x.notificationMessage, x.userEmail, nService.getInterestNamesByPushNotificationId(x.pushNotificationId), nService.getIEventTitlesByPushNotificationId(x.pushNotificationId))).ToList();
}
public NotificationViewModelUI(int conferenceId, int pushNotificationId, int notificationId, string notificationType, DateTime dateTime, int criteria, string nMessage, string emailId = null, string interestNames = null, string eventTitles = null)
{
this.conferenceId = conferenceId;
this.pushNotificationId = pushNotificationId;
this.notificationId = notificationId;
this.notificationType = notificationType;
this.notificationDate = dateTime;
this.sendCriteria = (NotificationCriteria)criteria;
this.notificationMessage = nMessage;
this.emailId = NotificationCriteria.SpecificUser.Description() +"... "+ emailId;
this.interestNames = NotificationCriteria.UserByInterests.Description() + "... " + interestNames;
this.eventTitles = NotificationCriteria.UserByEvents.Description() + "... " + eventTitles;
}
I have 2 objects (lists loaded from XML) report and database (showed bellow in code) and i should analyse them and mark items with 0, 1, 2, 3 according to some conditions
TransactionResultCode = 0; // SUCCESS (all fields are equivalents: [Id, AccountNumber, Date, Amount])
TransactionResultCode = 1; // Exists in report but Not in database
TransactionResultCode = 2; // Exists in database but Not in report
TransactionResultCode = 3; // Field [Id] are equals but other fields [AccountNumber, Date, Amount] are different.
I'll be happy if somebody could found time to suggest how to optimize some queries.
Bellow is the code:
THANK YOU!!!
//TransactionResultCode = 0 - SUCCESS
//JOIN on all fields
var result0 = from d in database
from r in report
where (d.TransactionId == r.MovementID) &&
(d.TransactionAccountNumber == long.Parse(r.AccountNumber)) &&
(d.TransactionDate == r.MovementDate) &&
(d.TransactionAmount == r.Amount)
orderby d.TransactionId
select new TransactionList()
{
TransactionId = d.TransactionId,
TransactionAccountNumber = d.TransactionAccountNumber,
TransactionDate = d.TransactionDate,
TransactionAmount = d.TransactionAmount,
TransactionResultCode = 0
};
//*******************************************
//JOIN on [Id] field
var joinedList = from d in database
from r in report
where d.TransactionId == r.MovementID
select new TransactionList()
{
TransactionId = d.TransactionId,
TransactionAccountNumber = d.TransactionAccountNumber,
TransactionDate = d.TransactionDate,
TransactionAmount = d.TransactionAmount
};
//Difference report - database
var onlyReportID = report.Select(r => r.MovementID).Except(joinedList.Select(d => d.TransactionId));
//TransactionResultCode = 1 - Not Found in database
var result1 = from o in onlyReportID
from r in report
where (o == r.MovementID)
orderby r.MovementID
select new TransactionList()
{
TransactionId = r.MovementID,
TransactionAccountNumber = long.Parse(r.AccountNumber),
TransactionDate = r.MovementDate,
TransactionAmount = r.Amount,
TransactionResultCode = 1
};
//*******************************************
//Difference database - report
var onlyDatabaseID = database.Select(d => d.TransactionId).Except(joinedList.Select(d => d.TransactionId));
//TransactionResultCode = 2 - Not Found in report
var result2 = from o in onlyDatabaseID
from d in database
where (o == d.TransactionId)
orderby d.TransactionId
select new TransactionList()
{
TransactionId = d.TransactionId,
TransactionAccountNumber = d.TransactionAccountNumber,
TransactionDate = d.TransactionDate,
TransactionAmount = d.TransactionAmount,
TransactionResultCode = 2
};
//*******************************************
var qwe = joinedList.Select(j => j.TransactionId).Except(result0.Select(r => r.TransactionId));
//TransactionResultCode = 3 - Transaction Results are different (Amount, AccountNumber, Date, )
var result3 = from j in joinedList
from q in qwe
where j.TransactionId == q
select new TransactionList()
{
TransactionId = j.TransactionId,
TransactionAccountNumber = j.TransactionAccountNumber,
TransactionDate = j.TransactionDate,
TransactionAmount = j.TransactionAmount,
TransactionResultCode = 3
};
you may try something like below:
public void Test()
{
var report = new[] {new Item(1, "foo", "boo"), new Item(2, "foo2", "boo2"), new Item(3, "foo3", "boo3")};
var dataBase = new[] {new Item(1, "foo", "boo"), new Item(2, "foo22", "boo2"), new Item(4, "txt", "rt")};
Func<Item, bool> inBothLists = (i) => report.Contains(i) && dataBase.Contains(i);
Func<IEnumerable<Item>, Item, bool> containsWithID = (e, i) => e.Select(_ => _.ID).Contains(i.ID);
Func<Item, int> getCode = i =>
{
if (inBothLists(i))
{
return 0;
}
if(containsWithID(report, i) && containsWithID(dataBase, i))
{
return 3;
}
if (report.Contains(i))
{
return 2;
}
else return 1;
};
var result = (from item in dataBase.Union(report) select new {Code = getCode(item), Item = item}).Distinct();
}
public class Item
{
// You need also to override Equals() and GetHashCode().. I omitted them to save space
public Item(int id, string text1, string text2)
{
ID = id;
Text1 = text1;
Text2 = text2;
}
public int ID { get; set; }
public string Text1 { get; set; }
public string Text2 { get; set; }
}
Note that you need to either implement Equals() for you items, or implement an IEqualityComparer<> and feed it to Contains() methods.
I have this LINQ statement as follows;
var RequestList = (from emp in _employeeIds
from x in db.AnnualLeaveBookeds
where x.EmployeeId == emp
orderby x.AnnualLeaveDate
select new RequestInfo
{
AnnualLeaveBookedId = x.AnnualLeaveBookedId,
AnnualLeaveDate = x.AnnualLeaveDate,
MorningOnlyFlag = x.MorningOnlyFlag,
AfternoonOnlyFlag = x.AfternoonOnlyFlag,
Forename = x.Employee.Forename,
Surname = x.Employee.Surname,
EmployeeId = x.Employee.EmployeeId,
RequestDate = x.RequestDate,
CancelRequestDate = x.CancelRequestDate,
ApprovedFlag = (x.ApprovalDate.HasValue && x.ApproverId != Employee.LoggedInUser.EmployeeId),
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty,
FontColour = "Black"
})
.ToList();
For every RequestInfo I return a FontColour property of Black.
However if I have 2 or more RequestInfo objects with the same AnnualLeaveDate, I want the FontColour to be set to red.
How do I rewrite this query to do that?
Try something like this:
var RequestList = (
from emp in _employeeIds
from x0 in db.AnnualLeaveBookeds
where x0.EmployeeId == emp
orderby x0.AnnualLeaveDate
group x0 by x0.AnnualLeaveDate into xs
from x in xs
select new RequestInfo
{
AnnualLeaveBookedId = x.AnnualLeaveBookedId,
AnnualLeaveDate = x.AnnualLeaveDate,
MorningOnlyFlag = x.MorningOnlyFlag,
AfternoonOnlyFlag = x.AfternoonOnlyFlag,
Forename = x.Employee.Forename,
Surname = x.Employee.Surname,
EmployeeId = x.Employee.EmployeeId,
RequestDate = x.RequestDate,
CancelRequestDate = x.CancelRequestDate,
ApprovedFlag = (x.ApprovalDate.HasValue
&& x.ApproverId != Employee.LoggedInUser.EmployeeId),
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty,
FontColour = xs.Count() > 1 ? "Red" : "Black"
}).ToList();
In her book Entity Framework Julie Lerman recommends using nested queries in preference to joins (scroll back a couple of pages).
In her example see populates 1 field this way, but what id you want to populate 2?
I have an example here where I would prefer to populate the Forename and Surname with the same nested query rather than 2 separate ones. I just need to know the correct syntax to do this.
public static List<RequestInfo> GetRequests(int _employeeId)
{
using (SHPContainerEntities db = new SHPContainerEntities())
{
return db.AnnualLeaveBookeds
.Where(x => x.NextApproverId == _employeeId ||
(x.ApproverId == _employeeId && x.ApprovalDate.HasValue == false))
.Select(y => new RequestInfo
{
AnnualLeaveDate = y.AnnualLeaveDate,
Forename = (
from e in db.Employees
where e.EmployeeId == y.EmployeeId
select e.Forename).FirstOrDefault(),
Surname = (
from e in db.Employees
where e.EmployeeId == y.EmployeeId
select e.Surname).FirstOrDefault(),
RequestDate = y.RequestDate,
CancelRequestDate = y.CancelRequestDate,
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty
})
.OrderBy(x => x.AnnualLeaveDate)
.ToList();
}
}
There's nothing wrong with your query, but you can write it in a way that is much simpler, without the nested queries:
public static List<RequestInfo> GetRequests(int employeeId)
{
using (SHPContainerEntities db = new SHPContainerEntities())
{
return (
from x in db.AnnualLeaveBookeds
where x.NextApproverId == employeeId ||
(x.ApproverId == employeeId && x.ApprovalDate == null)
orderby x.AnnualLeaveDate
select new RequestInfo
{
AnnualLeaveDate = x.AnnualLeaveDate,
Forename = x.Employee.Forename,
Surname = x.Employee.Surname,
RequestDate = x.RequestDate,
CancelRequestDate = x.CancelRequestDate,
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty
}).ToList();
}
}
See how I just removed your from e in db.Employees where ... select e.Forename) and simply replaced it with x.Employee.Forename. When your database contains the correct foreign key relationships, the EF designer will successfully generate a model that contain an Employee property on the AnnualLeaveBooked entity. Writing the query like this makes it much more readable.
I hope this helps.
try this
using (SHPContainerEntities db = new SHPContainerEntities())
{
return db.AnnualLeaveBookeds
.Where(x => x.NextApproverId == _employeeId ||
(x.ApproverId == _employeeId && x.ApprovalDate.HasValue == false))
.Select(y =>
{
var emp = db.Emplyees.Where(e => e.EmployeeId == y.EmployeeId);
return new RequestInfo
{
AnnualLeaveDate = y.AnnualLeaveDate,
Forename = emp.Forename,
Surname = emp.Surname,
RequestDate = y.RequestDate,
CancelRequestDate = y.CancelRequestDate,
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty
};
).OrderBy(x => x.AnnualLeaveDate).ToList();
}
Very primitive question but I am stuck (I guess being newbie). I have a function which is supposed to send me the list of companies : ALSO, I want the caller to be able to specify a top element for the drop-down list as well.. (say for "None"). I have following piece of code, how I will append the Top Element with the returning SelectList?
public static SelectList GetCompanies( bool onlyApproved, FCCIEntityDataContext entityDataContext, SelectListItem TopElement )
{
var cs = from c in entityDataContext.Corporates
where ( c.Approved == onlyApproved || onlyApproved == false )
select new
{
c.Id,
c.Company
};
return new SelectList( cs.AsEnumerable(), "Id", "Comapny" );
}
Thanks!
This should work for you:
List<Corporate> corporates =
(from c in entityDataContext.Corporates
where (c.Approved == onlyApproved || onlyApproved == false)
select c).ToList();
corporates.Add(new Corporate { Id = -1, Company = "None" });
return new SelectList(corporates.AsEnumerable(), "Id", "Comapny");
This method has always worked for me.
public static SelectList GetCompanies( bool onlyApproved, FCCIEntityDataContext entityDataContext, SelectListItem TopElement )
{
var cs = from c in entityDataContext.Corporates
where ( c.Approved == onlyApproved || onlyApproved == false )
select new SelectListItem {
Value = c.Id,
Text = c.Company
};
var list = cs.ToList();
list.Insert(0, TopElement);
var selectList = new SelectList( list, "Value", "Text" );
selectList.SelectedValue = TopElement.Value;
return selectList;
}
Update forgot the lesson I learned when I did this. You have to output the LINQ as SelectListItem.
cs.ToList().Insert(0, new { TopElement.ID, TopElement.Company });
You could convert it to a list as indicated or you could union the IQueryable result with a constant array of one element (and even sort it):
static void Main(string[] args)
{
var sampleData = new[] {
new { Id = 1, Company = "Acme", Approved = true },
new { Id = 2, Company = "Blah", Approved = true }
};
bool onlyApproved = true;
var cs = from c in sampleData
where (c.Approved == onlyApproved || onlyApproved == false)
select new
{
c.Id,
c.Company
};
cs = cs.Union(new [] {new { Id = -1, Company = "None" }}).OrderBy(c => c.Id);
foreach (var c in cs)
{
Console.WriteLine(String.Format("Id = {0}; Company = {1}", c.Id, c.Company));
}
Console.ReadKey();
}