public void Effort_FilterByMappedQuery()
{
using (var context = new TestDbContext(Effort.DbConnectionFactory.CreateTransient()))
{
// works but requires filters (Where, ...) to be specified before call to "Map"
// however, we'd like to apply filters to the resulting IQueryable "sourceResult".
// that does not work though.
IQueryable <OrderDto> sourceResult = new OrderDto[0]
.AsQueryable()
.Where(s => s.FullName.EndsWith("Bestellung"))
.Map <OrderDto, Order>(context.OrderSet)
.ProjectTo <OrderDto>(); // projection added
var dtos = sourceResult.ToList();
Assert.AreEqual(2, dtos.Count);
// this is what we try to achieve but it does not work
// as the mapping is done right away by "Map<>" and "ProjectTo<>"
// and the .Where() filter does not at that time
// so it is not mapped and results in a
// "System.NotSupportedException : The specified type member 'FullName' is not supported
// ...in LINQ to Entities. Only initializers, entity members, and entity navigation properties
// ...are supported."
try
{
IQueryable <OrderDto> sourceResult2 = new OrderDto[0]
.AsQueryable()
.Map <OrderDto, Order>(context.OrderSet)
.ProjectTo <OrderDto>(); // projection added
var dtos2 = sourceResult
.Where(s => s.FullName.EndsWith("Bestellung"))
.ToList();
//Assert.Fail("NotSupportedException was expected");
}
catch (NotSupportedException)
{
}
// Using "AsDataSource"
IQueryable <OrderDto> sourceResult4 = context.OrderSet.UseAsDataSource(Mapper.Configuration).For <OrderDto>();
var dtos4 = sourceResult4.Where(d => d.FullName.EndsWith("Bestellung")).ToList();
Assert.AreEqual(2, dtos4.Count);
}
}