//
// If member is a virtual member that implicitly overrides a member in a base class, return the overridden member.
// Otherwise, return null.
//
// - MethodImpls ignored. (I didn't say it made sense, this is just how the desktop api we're porting behaves.)
// - Implemented interfaces ignores. (I didn't say it made sense, this is just how the desktop api we're porting behaves.)
//
public static M GetImplicitlyOverriddenBaseClassMember <M>(this M member) where M : MemberInfo
{
MemberPolicies <M> policies = MemberPolicies <M> .Default;
MethodAttributes visibility;
bool isStatic;
bool isVirtual;
bool isNewSlot;
policies.GetMemberAttributes(member, out visibility, out isStatic, out isVirtual, out isNewSlot);
if (isNewSlot || !isVirtual)
{
return(null);
}
String name = member.Name;
TypeInfo typeInfo = member.DeclaringType.GetTypeInfo();
for (; ;)
{
Type baseType = typeInfo.BaseType;
if (baseType == null)
{
return(null);
}
typeInfo = baseType.GetTypeInfo();
foreach (M candidate in policies.GetDeclaredMembers(typeInfo))
{
if (candidate.Name != name)
{
continue;
}
MethodAttributes candidateVisibility;
bool isCandidateStatic;
bool isCandidateVirtual;
bool isCandidateNewSlot;
policies.GetMemberAttributes(member, out candidateVisibility, out isCandidateStatic, out isCandidateVirtual, out isCandidateNewSlot);
if (!isCandidateVirtual)
{
continue;
}
if (!policies.AreNamesAndSignatureEqual(member, candidate))
{
continue;
}
return(candidate);
}
}
}
//
// The iterator worker for GetMember<M>()
//
private static IEnumerable <M> GetMembersWorker <M>(Type type, String optionalNameFilter, BindingFlags bindingFlags) where M : MemberInfo
{
Type reflectedType = type;
Type typeOfM = typeof(M);
Type typeOfEventInfo = typeof(EventInfo);
MemberPolicies <M> policies = MemberPolicies <M> .Default;
bindingFlags = policies.ModifyBindingFlags(bindingFlags);
LowLevelList <M> overridingMembers = new LowLevelList <M>();
StringComparison comparisonType = (0 != (bindingFlags & BindingFlags.IgnoreCase)) ? StringComparison.CurrentCultureIgnoreCase : StringComparison.CurrentCulture;
bool inBaseClass = false;
bool nameFilterIsPrefix = false;
if (optionalNameFilter != null && optionalNameFilter.EndsWith("*", StringComparison.Ordinal))
{
nameFilterIsPrefix = true;
optionalNameFilter = optionalNameFilter.Substring(0, optionalNameFilter.Length - 1);
}
while (type != null)
{
TypeInfo typeInfo = type.GetTypeInfo();
foreach (M member in policies.GetDeclaredMembers(typeInfo))
{
if (optionalNameFilter != null)
{
if (nameFilterIsPrefix)
{
if (!member.Name.StartsWith(optionalNameFilter, comparisonType))
{
continue;
}
}
else if (!member.Name.Equals(optionalNameFilter, comparisonType))
{
continue;
}
}
MethodAttributes visibility;
bool isStatic;
bool isVirtual;
bool isNewSlot;
policies.GetMemberAttributes(member, out visibility, out isStatic, out isVirtual, out isNewSlot);
BindingFlags memberBindingFlags = (BindingFlags)0;
memberBindingFlags |= (isStatic ? BindingFlags.Static : BindingFlags.Instance);
memberBindingFlags |= ((visibility == MethodAttributes.Public) ? BindingFlags.Public : BindingFlags.NonPublic);
if ((bindingFlags & memberBindingFlags) != memberBindingFlags)
{
continue;
}
bool passesVisibilityScreen = true;
if (inBaseClass && visibility == MethodAttributes.Private)
{
passesVisibilityScreen = false;
}
bool passesStaticScreen = true;
if (inBaseClass && isStatic && (0 == (bindingFlags & BindingFlags.FlattenHierarchy)))
{
passesStaticScreen = false;
}
//
// Desktop compat: The order in which we do checks is important.
//
if (!passesVisibilityScreen)
{
continue;
}
if ((!passesStaticScreen) && !(typeOfM.Equals(typeOfEventInfo)))
{
continue;
}
bool isImplicitlyOverridden = false;
if (isVirtual)
{
if (isNewSlot)
{
// A new virtual member definition.
for (int i = 0; i < overridingMembers.Count; i++)
{
if (policies.AreNamesAndSignatureEqual(member, overridingMembers[i]))
{
// This member is overridden by a more derived class.
isImplicitlyOverridden = true;
overridingMembers.RemoveAt(i);
break;
}
}
}
else
{
for (int i = 0; i < overridingMembers.Count; i++)
{
if (policies.AreNamesAndSignatureEqual(overridingMembers[i], member))
{
// This member overrides another, *and* is overridden by yet another method.
isImplicitlyOverridden = true;
break;
}
}
if (!isImplicitlyOverridden)
{
// This member overrides another and is the most derived instance of it we've fonud.
overridingMembers.Add(member);
}
}
}
if (isImplicitlyOverridden)
{
continue;
}
if (!passesStaticScreen)
{
continue;
}
if (inBaseClass)
{
yield return(policies.GetInheritedMemberInfo(member, reflectedType));
}
else
{
yield return(member);
}
}
if (0 != (bindingFlags & BindingFlags.DeclaredOnly))
{
break;
}
inBaseClass = true;
type = typeInfo.BaseType;
}
}
