Simple.Data casting to ToList()

Question

I am using Simple.Data and want to know if I can Select a single column and then cast it to a list of string values. For example using the query below I get the error:

Cannot implicitly convert type 'Simple.Data.SimpleRecord' to 'string'

var result = _database.ParentRegionList.All()
            .Select(_database.ParentRegionList.RegionName)
            .Where(_database.ParentRegionList.RegionName.Like(startsWith + "%"))
            .Distinct()
            .ToList<string>();

However if I create a class LocationAutoComplete that has a single public property "RegionName" of type string then the cast works fine.

var result = _database.ParentRegionList.All()
            .Select(_database.ParentRegionList.RegionName)
            .Where(_database.ParentRegionList.RegionName.Like(startsWith + "%"))
            .Distinct()
            .ToList<LocationAutoComplete>();

Your statement looks buggy. Shouldn't `.Select()` and `.Where()` take a predicate? — Ken Kin, Jan 20 '13 at 23:26
@KenKin, i'd assume that is how the framework they are using works. — Ash Burlaczenko, Jan 20 '13 at 23:31
What is the data type of RegionName? If RegionName is already a varchar or string, you shouldn't have to convert it to string — DJ Burb, Jan 21 '13 at 00:09

score 3 · Accepted Answer · answered Jan 21 '13 at 14:15

The ToList<T> Simple.Data method expects you to be casting the contents of a SimpleRecord to an object, which is why it works with your LocationAutoComplete class. Full details can be found here.

If you are returning only one field which you wish to return as a scalar value or a list of scalar values, use the ToScalar<T> or ToScalarList<T> method instead. Full details can be found here

DJ Burb · Answer 2 · 2013-01-21T00:45:41.823

0

If RegionName is a varchar then all you need is

var result = _database.ParentRegionList.All()                
            .Where(_database.ParentRegionList.RegionName.Like(startsWith + "%"))
            .Select(_database.ParentRegionList.RegionName)
            .Distinct()
            .ToList();

You don't need the <string>

edited Jan 21 '13 at 00:45

answered Jan 21 '13 at 00:34

DJ Burb

2,346
2
29
38

That gives me a list of SimpleRecord objects, Sorry I also miss read the column type is actually nvarchar – Dave Jan 21 '13 at 00:40
Try doing the Where before the Select. I'll edit my answer, so you can see – DJ Burb Jan 21 '13 at 00:44
What if you do a lambda statement in the where clause? Like so, var result = _database.ParentRegionList. .Where(p=>p.RegionName.Contains(startsWith)) .Select(p=>p.RegionName) .Distinct() .ToList(); – DJ Burb Jan 21 '13 at 00:52
you shouldn't need that All() either – DJ Burb Jan 21 '13 at 00:54

Simple.Data casting to ToList()

2 Answers2