public override void Emit <T>(Emit <T> emitter)
{
_finBlock.Block = emitter.BeginFinallyBlock(_exBlock.Block);
}
public static Emit <Func <IEnumerable <object>, IEnumerable <T> > > GenerateMapper <T>()
{
Type type = typeof(T);
Emit <Func <IEnumerable <object>, IEnumerable <T> > > emit = null;
if (_mappers.ContainsKey(type.FullName))
{
emit = (Emit <Func <IEnumerable <object>, IEnumerable <T> > >)_mappers[type.FullName];
}
else
{
ConstructorInfo listConstructor = typeof(List <T>).GetConstructor(new Type[] { });
MethodInfo listAdd = typeof(List <T>).GetMethod("Add", new Type[] { typeof(T) });
Emit <Func <IEnumerable <object>, IEnumerable <T> > > emiter = Emit <Func <IEnumerable <object>, IEnumerable <T> > > .NewDynamicMethod(type.Name + "Mapper");
var enumeratorLocal = emiter.DeclareLocal <IEnumerator <object> >("enumerator");
var listLocal = emiter.DeclareLocal <List <T> >("list");
var cacheLocal = emiter.DeclareLocal <IDictionary <object, object> >("cache");
var loopFinishedLabel = emiter.DefineLabel("loopFinished");
var loopCheckLabel = emiter.DefineLabel("loopCheck");
var loopBeginLabel = emiter.DefineLabel("loopBegin");
var finallyFinishedLabel = emiter.DefineLabel("finallyFinished");
var isNullLabel = emiter.DefineLabel("isNull");
emiter.NewObject(listConstructor);
emiter.StoreLocal(listLocal);
emiter.NewObject(DictionaryConstructor_Object_Object);
emiter.StoreLocal(cacheLocal);
emiter.LoadArgument(0);
emiter.CallVirtual(IEnumerable_Object_GetEnumerator);
emiter.StoreLocal(enumeratorLocal);
//try {
var exceptionBlock = emiter.BeginExceptionBlock();
emiter.Branch(loopCheckLabel);
emiter.MarkLabel(loopBeginLabel);
emiter.LoadLocal(listLocal);
emiter.LoadLocal(enumeratorLocal);
emiter.CallVirtual(IEnumerator_Object_GetCurrent);
emiter.CastClass <IDictionary <string, object> >();
emiter.LoadLocal(cacheLocal);
emiter.LoadConstant("");
emiter.Call(GenerateRowMapper(type)); // var rowResult = rowMapper ( row, cache, depthString = "" );
emiter.Duplicate();
emiter.LoadNull();
emiter.BranchIfEqual(isNullLabel);
emiter.CastClass(typeof(T));
emiter.Call(listAdd); // listLocal.Add((T)rowResult);
emiter.Branch(loopCheckLabel);
emiter.MarkLabel(isNullLabel);
emiter.Pop();
emiter.Pop();
emiter.MarkLabel(loopCheckLabel);
emiter.LoadLocal(enumeratorLocal);
emiter.CallVirtual(IEnumerator_MoveNext);
emiter.BranchIfTrue(loopBeginLabel);
emiter.Leave(loopFinishedLabel);
//}
//finallY {
var finallyBlock = emiter.BeginFinallyBlock(exceptionBlock);
emiter.LoadNull();
emiter.LoadLocal(enumeratorLocal);
emiter.CompareEqual();
emiter.BranchIfTrue(finallyFinishedLabel);
emiter.LoadLocal(enumeratorLocal);
emiter.CallVirtual(IEnumerator_Dispose);
emiter.MarkLabel(finallyFinishedLabel);
emiter.EndFinallyBlock(finallyBlock);
emiter.EndExceptionBlock(exceptionBlock);
//}
emiter.MarkLabel(loopFinishedLabel);
emiter.LoadLocal(listLocal);
emiter.Return(); // return listLocal;
_mapperDelegates.Add(type.FullName, emiter.CreateDelegate());
_mappers.Add(type.FullName, emiter);
emit = emiter;
}
return(emit);
}
