public static DynamicBuilder <T> CreateBuilder(IDataRecord dataRecord)
{
var dynamicBuilder = new DynamicBuilder <T>();
var method = new DynamicMethod("DynamicCreate", typeof(T), new[] { typeof(IDataRecord) },
typeof(T), true);
var generator = method.GetILGenerator();
var result = generator.DeclareLocal(typeof(T));
if (IsSingleType(typeof(T)))
{
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldc_I4, 0);
generator.Emit(OpCodes.Callvirt, getValueMethod);
generator.Emit(OpCodes.Unbox_Any, dataRecord.GetFieldType(0));
generator.Emit(OpCodes.Ret);
}
else
{
generator.Emit(OpCodes.Newobj, typeof(T).GetConstructor(Type.EmptyTypes));
generator.Emit(OpCodes.Stloc, result);
for (var i = 0; i < dataRecord.FieldCount; i++)
{
var propertyInfo = typeof(T).GetProperty(dataRecord.GetName(i), BindingFlags.Instance | BindingFlags.Public | BindingFlags.IgnoreCase);
var endIfLabel = generator.DefineLabel();
if (propertyInfo == null)
{
continue;
}
var proMethod = propertyInfo.GetSetMethod();
if (proMethod == null)
{
continue;
}
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldc_I4, i);
generator.Emit(OpCodes.Callvirt, isDBNullMethod);
generator.Emit(OpCodes.Brtrue, endIfLabel);
generator.Emit(OpCodes.Ldloc, result);
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldc_I4, i);
generator.Emit(OpCodes.Callvirt, getValueMethod);
generator.Emit(OpCodes.Unbox_Any, propertyInfo.PropertyType);
generator.Emit(OpCodes.Callvirt, proMethod);
generator.MarkLabel(endIfLabel);
}
generator.Emit(OpCodes.Ldloc, result);
generator.Emit(OpCodes.Ret);
}
dynamicBuilder._handler = (Load)method.CreateDelegate(typeof(Load));
return(dynamicBuilder);
}
private static List <T> MappingReaderToList <T>(IDbCommand dbCommand)
{
using (var dataReader = dbCommand.ExecuteReader())
{
if (dataReader.FieldCount == 0)
{
return(null);
}
var recordList = new List <T>();
var builder = DynamicBuilder <T> .CreateBuilder(dataReader);
while (dataReader.Read())
{
var record = builder.Build(dataReader);
recordList.Add(record);
}
return(recordList);
}
}
private static T MappingReadToSingle <T>(IDbCommand dbCommand)
{
using (var dataReader = dbCommand.ExecuteReader())
{
if (dataReader.FieldCount == 0)
{
return(default(T));
}
var builder = DynamicBuilder <T> .CreateBuilder(dataReader);
if (!dataReader.Read())
{
return(default(T));
}
var record = builder.Build(dataReader);
if (dataReader.Read())
{
throw new Exception("The result is not single row.");
}
return(record);
}
}
