Error Operator && cannot be applied to operands of type int ? & int

Ramco Ramco

4y1.2k.NET

When i add && t.studentid equals t2.studentid then i get above error

public List GetOrderingInput()
{
List Result = (from t in context.View_SessionDeliveryCalendarDetails_Students
join t2 in context.View_BookDeliveryDetails
on t.BookID equals t2.BookID && t2.StudentID equals t2.studentid
where t.CurrentStatus == "Due"
orderby t.Name
select t).ToList();
return Result;
}

Thanks

7 Replies

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Ramco Ramco4y ago
Hi sachin

When i write like below then it is showing no error. Both sides int

on new { p1 = (int)t.BookID, p2 = (int)t.StudentID} equals new { p1 = (int)t2.BookID, p2 = (int)t2.StudentID }

Thanks
Ramco Ramco4y ago
Hi Sachin

I will try but the same code it it possible to access fields from t & t2 in aspx page
Do i need to change

Thanks
Sachin Singh4y ago
Then use properties
OK
public List GetOrderingInput()
{
List Result = (from t in context.View_SessionDeliver yCalendarDetails_Students
join t2 in context.View_BookDeliverytails
on new {p1= t.BookID, p2=t.Studentid } equals new {p1=(int) t2.BookID, p2=(int)t2.StudentID}
where t.CurrentStatus == "Due"
orderby t.Name
select t).ToList();
return Result;
}
Ramco Ramco4y ago
Hi

Now it is giving error Invalid Annonymous type member declarator

on (int) t2.BookID, (int) t2.StudentID

Thanks
Sachin Singh4y ago
Then typecast it
List Result = (from t in context.View_SessionDeliveryCalendarDetails_Students
join t2 in context.View_BookDeliveryDetails
on new { t.BookID, t.StudentID } equals new {(int) t2.BookID, (int) t2.StudentID }
where t.CurrentStatus == "Due"
orderby t.Name
select t).ToList();
all 4 should be of same type.
Ramco Ramco4y ago
Hi

It is giving error = the type of one of the expressions in join clause is incorrect

List Result = (from t in context.View_SessionDeliveryCalendarDetails_Students
join t2 in context.View_BookDeliveryDetails
on new { t.BookID, t.StudentID } equals new { t2.BookID, t2.StudentID }
where t.CurrentStatus == "Due"
orderby t.Name
select t).ToList();

Thanks
Sachin Singh4y ago
With Linq you can't join on multiple columns like that.
Use below code instead
public List GetOrderingInput()
{
List Result = (from t in context.View_SessionDeliver yCalendarDetails_Students
join t2 in context.View_BookDeliverytails
on new { t.BookID, t.Studentid } equals new { t2.BookID, t2.StudentID}

where t.CurrentStatus == "Due"
orderby t.Name
select t).ToList();
return Result;
}