How can I map a DataReader object into a class object by using generics?
For example I need to do the following:
public class Mapper<T>
{
public static List<T> MapObject(IDataReader dr)
{
List<T> objects = new List<T>();
while (dr.Read())
{
//Mapping goes here...
}
return objects;
}
}
And later I need to call this class-method like the following:
IDataReder dataReader = DBUtil.Fetchdata("SELECT * FROM Book");
List<Book> bookList = Mapper<Book>.MapObject(dataReder);
foreach (Book b in bookList)
{
Console.WriteLine(b.ID + ", " + b.BookName);
}
Note that, the Mapper - class should be able to map object of any type represented by T.
I use ValueInjecter for this
I'm doing like this:
while (dr.Read())
{
var o = new User();
o.InjectFrom<DataReaderInjection>(dr);
yield return o;
}
you gonna need this ValueInjection for this to work:
public class DataReaderInjection : KnownSourceValueInjection<IDataReader>
{
protected override void Inject(IDataReader source, object target, PropertyDescriptorCollection targetProps)
{
for (var i = 0; i < source.FieldCount; i++)
{
var activeTarget = targetProps.GetByName(source.GetName(i), true);
if (activeTarget == null) continue;
var value = source.GetValue(i);
if (value == DBNull.Value) continue;
activeTarget.SetValue(target, value);
}
}
}