public ReflectionInvoker(Type type, string name)
{
Name = name;
List = TypeHelper.GetMemberInfoList(type, name);
Last = List.Last();
DataType = TypeHelper.GetMemberType(Last);
TargetType = type;
}
public static Func <T, V> GetInvokerGet(string name, List <MemberInfo> list)
{
var first = list.First();
var method = new DynamicMethod($"{first.DeclaringType.Name}.{name}Get",
typeof(V),
new Type[] { typeof(T) },
true);
ILGenerator il = method.GetILGenerator();
var locals = new LocalBuilder[list.Count];
var lables = new Label[(list.Count - 1) * 2];
for (int i = 0; i < list.Count; i++)
{
var info = list[i];
locals[i] = il.DeclareLocal(TypeHelper.GetMemberType(info));
}
for (int i = 0; i < lables.Length; i++)
{
var info = list[i / 2];
if (!TypeHelper.GetMemberType(info).IsValueType)
{
lables[i] = il.DefineLabel();
}
}
EmitLoadArgument(il, typeof(T));
int j = 0;
for (int i = 0; i < list.Count; i++)
{
var info = list[i];
var type = TypeHelper.GetMemberType(info);
EmitCallGet(il, info);
if (i < list.Count - 1)
{
il.Emit(OpCodes.Stloc, locals[i]);
if (!type.IsValueType)
{
il.Emit(OpCodes.Ldloc, locals[i]);
il.Emit(OpCodes.Brtrue_S, lables[j + 1]);
il.MarkLabel(lables[j++]);
il.Emit(OpCodes.Ldloc, locals[list.Count - 1]);
il.Emit(OpCodes.Ret);
il.MarkLabel(lables[j++]);
}
EmitLoadLocal(il, locals[i]);
}
}
il.Emit(OpCodes.Ret);
return((Func <T, V>)method.CreateDelegate(typeof(Func <T, V>)));
}
public static IInvoker Initialize(Type type, string property)
{
if (property == null)
return null;
var list = TypeHelper.GetMemberInfoList(type, property);
if (list.Count == 1)
{
return Initialize(list[0].Info, list[0].Index == null, list[0].Index);
}
if (list.Count > 1)
{
var last = list.Last();
var emittype = typeof(ComplexInvoker<,>).MakeGenericType(type, TypeHelper.GetMemberType(last.Info));
return (IInvoker)CreateObject(emittype, new[] { typeof(string), typeof(List<MemberParseInfo>) }, new object[] { property, list }, true);
}
return null;
}
//https://stackoverflow.com/a/39617419/4682355
public static Expression CreateNullPropagationExpression(Expression o, Expression call, MemberInfo memberInfo)
{
Expression propertyAccess = call;
var propertyType = TypeHelper.GetMemberType(memberInfo);
if (propertyType.IsValueType && !TypeHelper.IsNullable(propertyType))
{
return(propertyAccess);
}
var nullResult = Expression.Default(propertyAccess.Type);
var condition = Expression.Equal(o, Expression.Constant(null, o.Type));
return(Expression.Condition(condition, nullResult, propertyAccess));
}
public static Action <T, V> GetInvokerSet(string name, List <MemberInfo> list)
{
var last = list.Last();
foreach (var item in list)
{
if (item is PropertyInfo &&
((PropertyInfo)item).PropertyType.IsValueType &&
(!((PropertyInfo)item).CanWrite || ((PropertyInfo)item).GetSetMethod() == null))
{
return(null);
}
}
if (last is MethodInfo ||
(last is PropertyInfo &&
(!((PropertyInfo)last).CanWrite || ((PropertyInfo)last).GetSetMethod() == null)))
{
return(null);
}
var first = list.First();
DynamicMethod method = new DynamicMethod($"{first.DeclaringType.Name}.{name}Set",
typeof(void),
new Type[] { typeof(T), typeof(V) }, true);
var il = method.GetILGenerator();
var locals = new LocalBuilder[list.Count - 1];
var lables = new Label[list.Count + 1];
for (int i = 0; i < list.Count - 1; i++)
{
var info = list[i];
locals[i] = il.DeclareLocal(TypeHelper.GetMemberType(info));
}
for (int i = 0; i <= list.Count; i++)
{
lables[i] = il.DefineLabel();
}
EmitLoadArgument(il, typeof(T));
int j = 0;
for (int i = 0; i < list.Count; i++)
{
var info = list[i];
var type = TypeHelper.GetMemberType(info);
if (i < list.Count - 1)
{
EmitCallGet(il, info);
il.Emit(OpCodes.Stloc, locals[i]);
if (!type.IsValueType)
{
il.Emit(OpCodes.Ldloc, locals[i]);
il.Emit(OpCodes.Brfalse_S, lables[lables.Length - 1]);
il.MarkLabel(lables[j++]);
}
EmitLoadLocal(il, locals[i]);
}
else
{
il.Emit(OpCodes.Ldarg_1);
EmitCallSet(il, info);
for (int r = list.Count - 2; r >= 0; r--)
{
info = list[r];
type = TypeHelper.GetMemberType(info);
if (type.IsValueType)
{
if (r == 0)
{
EmitLoadArgument(il, typeof(T));
}
else
{
EmitLoadLocal(il, locals[r - 1]);
}
il.Emit(OpCodes.Ldloc, locals[r]);//EmitLoadLocal(il, locals[r]);
EmitCallSet(il, info);
}
}
}
}
if (j > 0)
{
il.MarkLabel(lables[lables.Length - 1]);
}
il.Emit(OpCodes.Ret);
var handler = (Action <T, V>)method.CreateDelegate(typeof(Action <T, V>));
return(handler);
}
public static Action <T, V> GetExpressionSet(string name, List <MemberParseInfo> list)
{
var last = list.Last();
var first = list.First();
var target = Expression.Parameter(typeof(T), "target");
var value = Expression.Parameter(typeof(V), "value");
var returnLabel = Expression.Label();
var locals = new ParameterExpression[list.Count - 1];
var labels = new LabelTarget[list.Count];
List <Expression> body = new List <Expression>();
for (int i = 0; i < list.Count - 1; i++)
{
var info = list[i];
locals[i] = Expression.Variable(TypeHelper.GetMemberType(info.Info), info.Info.Name.ToLower());
}
for (int i = 0; i < list.Count; i++)
{
labels[i] = Expression.Label();
}
int j = 0;
for (int i = 0; i < list.Count; i++)
{
var info = list[i];
var type = TypeHelper.GetMemberType(info.Info);
if (i < list.Count - 1)
{
var call = Call(i == 0 ? target : locals[i - 1], info, i);
body.Add(Expression.Assign(locals[i], call));
if (!type.IsValueType || TypeHelper.IsNullable(type))
{
body.Add(Expression.IfThenElse(Expression.Equal(locals[i], Expression.Constant(null, type)),
Expression.Return(returnLabel),
Expression.Label(labels[j++])));
}
}
else
{
for (int r = list.Count - 1; r >= 0; r--)
{
info = list[r];
type = TypeHelper.GetMemberType(info.Info);
if (type.IsValueType || r == list.Count - 1)
{
var param = r == 0 ? target : locals[r - 1];
var setValue = r == list.Count - 1 ? value : locals[r];
if (TypeHelper.CanWrite(info.Info))
{
var call = Call(param, info, r);
body.Add(Expression.Assign(call, setValue));
}
else
{
return(null);
}
}
}
}
}
if (j > 0)
{
body.Add(Expression.Label(returnLabel));
}
return(Expression.Lambda <Action <T, V> >(Expression.Block(locals, body), target, value).Compile());
}