public override DynamicMetaObject BindCreateInstance(
CreateInstanceBinder binder, DynamicMetaObject[] args)
{
var constructors = ReflType.GetConstructors();
var ctors = constructors.
Where(c => c.GetParameters().Length == args.Length);
List <ConstructorInfo> res = new List <ConstructorInfo>();
foreach (var c in ctors)
{
if (RuntimeHelpers.ParametersMatchArguments(c.GetParameters(),
args))
{
res.Add(c);
}
}
if (res.Count == 0)
{
// Binders won't know what to do with TypeModels, so pass the
// RuntimeType they represent. The binder might not be Sympl's.
return(binder.FallbackCreateInstance(
RuntimeHelpers.GetRuntimeTypeMoFromModel(this),
args));
}
// For create instance of a TypeModel, we can create a instance
// restriction on the MO, hence the true arg.
var restrictions = RuntimeHelpers.GetTargetArgsRestrictions(
this, args, true);
var ctorArgs =
RuntimeHelpers.ConvertArguments(
args, res[0].GetParameters());
return(new DynamicMetaObject(
// Creating an object, so don't need EnsureObjectResult.
Expression.New(res[0], ctorArgs),
restrictions));
}
// Because we don't ComboBind over several MOs and operations, and no one
// is falling back to this function with MOs that have no values, we
// don't need to check HasValue. If we did check, and HasValue == False,
// then would defer to new InvokeMemberBinder.Defer().
//
public override DynamicMetaObject BindInvokeMember(
InvokeMemberBinder binder, DynamicMetaObject[] args)
{
var flags = BindingFlags.IgnoreCase | BindingFlags.Static |
BindingFlags.Public;
var members = ReflType.GetMember(binder.Name, flags);
if ((members.Length == 1) && (members[0] is PropertyInfo ||
members[0] is FieldInfo))
{
// NEED TO TEST, should check for delegate value too
var mem = members[0];
throw new NotImplementedException();
//return new DynamicMetaObject(
// Expression.Dynamic(
// new SymplInvokeBinder(new CallInfo(args.Length)),
// typeof(object),
// args.Select(a => a.Expression).AddFirst(
// Expression.MakeMemberAccess(this.Expression, mem)));
// Don't test for eventinfos since we do nothing with them now.
}
else
{
// Get MethodInfos with right arg counts.
var mi_mems = members.
Select(m => m as MethodInfo).
Where(m => m is MethodInfo &&
((MethodInfo)m).GetParameters().Length ==
args.Length);
// Get MethodInfos with param types that work for args. This works
// for except for value args that need to pass to reftype params.
// We could detect that to be smarter and then explicitly StrongBox
// the args.
List <MethodInfo> res = new List <MethodInfo>();
foreach (var mem in mi_mems)
{
if (RuntimeHelpers.ParametersMatchArguments(
mem.GetParameters(), args))
{
res.Add(mem);
}
}
if (res.Count == 0)
{
// Sometimes when binding members on TypeModels the member
// is an intance member since the Type is an instance of Type.
// We fallback to the binder with the Type instance to see if
// it binds. The SymplInvokeMemberBinder does handle this.
var typeMO = RuntimeHelpers.GetRuntimeTypeMoFromModel(this);
var result = binder.FallbackInvokeMember(typeMO, args, null);
return(result);
}
// True below means generate an instance restriction on the MO.
// We are only looking at the members defined in this Type instance.
var restrictions = RuntimeHelpers.GetTargetArgsRestrictions(
this, args, true);
// restrictions and conversion must be done consistently.
var callArgs =
RuntimeHelpers.ConvertArguments(
args, res[0].GetParameters());
return(new DynamicMetaObject(
RuntimeHelpers.EnsureObjectResult(
Expression.Call(res[0], callArgs)),
restrictions));
// Could hve tried just letting Expr.Call factory do the work,
// but if there is more than one applicable method using just
// assignablefrom, Expr.Call throws. It does not pick a "most
// applicable" method or any method.
}
}