Question

I have a select query which is used over and over with different where filters:

var query = from row in context.Table select row;

How can I save this into a static class variable so I can reuse it in different methods? Like:

var results1 = query.Where(condition1);
...
var results2 = query.Where(condition2);

Answer 1

You’re on the right track.

Consider creating a new method instead of a variable:

public IQueryable<Cust> ListActiveCustomers()
{
     return dataContext.Customers.Where(c=>c.IsActive==true);
}

You can then consume this from anywhere that method is visible:

 //Active Customers with no invoices due.
 var activePaidCustomers = ListActiveCustomers().Where(c=>c.InvoicesDue==0)
                                                .OrderByDescending(c=>c.LastPaidOn)
                                                .ToList();