public Func <TEntity> GetFactory <TEntity>()
{
Type entityType = typeof(TEntity);
var constructorInfo = MemberAccessorBuilder.GetConstructor <TEntity>(Type.EmptyTypes);
if (constructorInfo == null)
{
throw new FlatFileException(Resources.NoDefaultConstructor);
}
var typeName = GetUniqueTypeName($"{entityType.Name}Factory");
var typeBuilder = moduleBuilder.DefineType(typeName, TypeAttributes.Class | TypeAttributes.Public | TypeAttributes.Sealed);
var methodBuilder = typeBuilder.DefineMethod("Create", MethodAttributes.Public | MethodAttributes.Static, entityType, Type.EmptyTypes);
var generator = methodBuilder.GetILGenerator();
generator.Emit(OpCodes.Newobj, constructorInfo);
generator.Emit(OpCodes.Ret);
var typeInfo = typeBuilder.CreateTypeInfo();
var createInfo = typeInfo.GetMethod(methodBuilder.Name);
return((Func <TEntity>)createInfo.CreateDelegate(typeof(Func <TEntity>)));
}
private static void EmitCustomWrite <TEntity>(
ILGenerator generator,
FieldInfo fieldInfo,
LocalBuilder contextBuilder,
LocalBuilder mappingBuilder,
int mappingIndex)
{
// Gets the mapping being processed
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldfld, fieldInfo);
generator.Emit(OpCodes.Ldc_I4, mappingIndex);
generator.Emit(OpCodes.Ldelem_Ref);
generator.Emit(OpCodes.Stloc, mappingBuilder);
// Create the ColumnContext
var contextCtorInfo = MemberAccessorBuilder.GetConstructor <ColumnContext>(Type.EmptyTypes);
generator.Emit(OpCodes.Newobj, contextCtorInfo);
// Set ColumnContext.RecordContext
generator.Emit(OpCodes.Dup);
generator.Emit(OpCodes.Ldarg_1);
var recordContextSetInfo = MemberAccessorBuilder.GetProperty <ColumnContext, IRecordContext>(x => x.RecordContext);
var recordContextSetter = recordContextSetInfo.GetSetMethod();
generator.Emit(OpCodes.Callvirt, recordContextSetter);
// Set ColumnContext.PhysicalIndex
generator.Emit(OpCodes.Dup);
generator.Emit(OpCodes.Ldloc, mappingBuilder);
var physicalIndexGetInfo = MemberAccessorBuilder.GetProperty <IMemberMapping, int>(x => x.PhysicalIndex);
var physicalIndexGetter = physicalIndexGetInfo.GetGetMethod();
var physicalIndexSetInfo = MemberAccessorBuilder.GetProperty <ColumnContext, int>(x => x.PhysicalIndex);
var physicalIndexSetter = physicalIndexSetInfo.GetSetMethod();
generator.Emit(OpCodes.Callvirt, physicalIndexGetter);
generator.Emit(OpCodes.Callvirt, physicalIndexSetter);
// Set ColumnContext.LogicalIndex
generator.Emit(OpCodes.Dup);
generator.Emit(OpCodes.Ldloc, mappingBuilder);
var logicalIndexGetInfo = MemberAccessorBuilder.GetProperty <IMemberMapping, int>(x => x.LogicalIndex);
var logicalIndexGetter = logicalIndexGetInfo.GetGetMethod();
var logicalIndexSetInfo = MemberAccessorBuilder.GetProperty <ColumnContext, int>(x => x.LogicalIndex);
var logicalIndexSetter = logicalIndexSetInfo.GetSetMethod();
generator.Emit(OpCodes.Callvirt, logicalIndexGetter);
generator.Emit(OpCodes.Callvirt, logicalIndexSetter);
generator.Emit(OpCodes.Stloc, contextBuilder);
// Get the writer
generator.Emit(OpCodes.Ldloc, mappingBuilder);
var writerInfo = MemberAccessorBuilder.GetProperty <IMemberMapping, Action <IColumnContext, object, object[]> >(x => x.Writer);
var writerGetter = writerInfo.GetGetMethod();
generator.Emit(OpCodes.Callvirt, writerGetter);
// Load the parameters
generator.Emit(OpCodes.Ldloc, contextBuilder);
generator.Emit(OpCodes.Ldarg_2);
generator.Emit(OpCodes.Ldarg_3);
// Invoke the writer
var invokeInfo = MemberAccessorBuilder.GetMethod <Action <IColumnContext, object, object> >(x => x.Invoke(null, null, null));
generator.Emit(OpCodes.Callvirt, invokeInfo);
}
