public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if (typeInfo == null)
{
return(false);
}
if (this == typeInfo)
{
return(true);
}
if (typeInfo.IsSubclassOf(this))
{
return(true);
}
if (base.IsInterface)
{
return(typeInfo.ImplementInterface(this));
}
if (this.IsGenericParameter)
{
Type[] genericParameterConstraints = this.GetGenericParameterConstraints();
for (int i = 0; i < genericParameterConstraints.Length; i++)
{
if (!genericParameterConstraints[i].IsAssignableFrom(typeInfo))
{
return(false);
}
}
return(true);
}
return(false);
}
public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if (typeInfo == null)
return false;
if (this == typeInfo)
return true;
// If c is a subclass of this class, then c can be cast to this type.
if (typeInfo.IsSubclassOf(this))
return true;
if (this.IsInterface)
{
return typeInfo.ImplementInterface(this);
}
else if (IsGenericParameter)
{
Type[] constraints = GetGenericParameterConstraints();
for (int i = 0; i < constraints.Length; i++)
if (!constraints[i].IsAssignableFrom(typeInfo))
return false;
return true;
}
return false;
}
public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if ((Type)typeInfo == (Type)null)
{
return(false);
}
if ((Type)this == (Type)typeInfo || typeInfo.IsSubclassOf((Type)this))
{
return(true);
}
if (this.IsInterface)
{
return(typeInfo.ImplementInterface((Type)this));
}
if (!this.IsGenericParameter)
{
return(false);
}
foreach (Type parameterConstraint in this.GetGenericParameterConstraints())
{
if (!parameterConstraint.IsAssignableFrom((Type)typeInfo))
{
return(false);
}
}
return(true);
}
public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if (typeInfo == null)
{
return(false);
}
if (this.Equals(typeInfo))
{
return(true);
}
// If c is a subclass of this class, then typeInfo can be cast to this type.
if (typeInfo.IsSubclassOf(this.AsType()))
{
return(true);
}
if (this.IsInterface)
{
foreach (Type implementedInterface in typeInfo.ImplementedInterfaces)
{
TypeInfo resolvedImplementedInterface = implementedInterface.GetTypeInfo();
if (resolvedImplementedInterface.Equals(this))
{
return(true);
}
}
return(false);
}
else if (IsGenericParameter)
{
Type[] constraints = GetGenericParameterConstraints();
for (int i = 0; i < constraints.Length; i++)
{
if (!constraints[i].GetTypeInfo().IsAssignableFrom(typeInfo))
{
return(false);
}
}
return(true);
}
return(false);
}
/// <summary>
/// Returns a value that indicates whether the specified type can be assigned to the current type.
/// </summary>
/// <param name="typeInfo">The type to check.</param>
/// <returns>True if the specified type can be assigned to this type; otherwise, False.</returns>
public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if (typeInfo == null)
{
return(false);
}
if (typeInfo == this)
{
return(true);
}
if (typeInfo.IsSubclassOf(this.AsType()))
{
return(true);
}
return(false);
}
//a re-implementation of ISAF from Type, skipping the use of UnderlyingType
public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if (typeInfo == null)
{
return(false);
}
if (this == typeInfo)
{
return(true);
}
// If c is a subclass of this class, then c can be cast to this type.
if (typeInfo.IsSubclassOf(this))
{
return(true);
}
if (this.IsInterface)
{
return(typeInfo.ImplementInterface(this));
}
else if (IsGenericParameter)
{
Type[] constraints = GetGenericParameterConstraints();
for (int i = 0; i < constraints.Length; i++)
{
if (!constraints[i].IsAssignableFrom(typeInfo))
{
return(false);
}
}
return(true);
}
return(false);
}
/// <summary>
/// Returns a value that indicates whether the specified type can be assigned to the current type.
/// </summary>
/// <param name="typeInfo">The type to check.</param>
/// <returns>True if the specified type can be assigned to this type; otherwise, False.</returns>
public virtual bool IsAssignableFrom(TypeInfo typeInfo)
{
if (typeInfo == null)
return false;
if (typeInfo == this)
return true;
if (typeInfo.IsSubclassOf(this.AsType()))
return true;
return false;
}
//
// Returns the effective set of custom attributes on a reflection element.
//
public IEnumerable <CustomAttributeData> GetMatchingCustomAttributes(E element, Type optionalAttributeTypeFilter, bool inherit, bool skipTypeValidation = false)
{
// Do all parameter validation here before we enter the iterator function (so that exceptions from validations
// show up immediately rather than on the first MoveNext()).
if (element == null)
{
throw new ArgumentNullException(nameof(element));
}
bool typeFilterKnownToBeSealed = false;
if (!skipTypeValidation)
{
if (optionalAttributeTypeFilter == null)
{
throw new ArgumentNullException("type");
}
TypeInfo attributeTypeFilterInfo = optionalAttributeTypeFilter.GetTypeInfo();
if (!(optionalAttributeTypeFilter.Equals(CommonRuntimeTypes.Attribute) ||
attributeTypeFilterInfo.IsSubclassOf(CommonRuntimeTypes.Attribute)))
{
throw new ArgumentException(SR.Argument_MustHaveAttributeBaseClass);
}
try
{
typeFilterKnownToBeSealed = attributeTypeFilterInfo.IsSealed;
}
catch (MissingMetadataException)
{
// If we got here, the custom attribute type itself was not opted into metadata. This can and does happen in the real world when an app
// contains a check for custom attributes that never actually appear on any entity within the app.
//
// Since "typeFilterKnownToBeSealed" is only used to enable an optimization, it's always safe to leave it "false".
//
// Because the Project N toolchain removes any custom attribute that refuses to opt into metadata so at this point,
// we could simply return an empty enumeration and "be correct." However, the code paths following this already do that naturally.
// (i.e. the "passFilter" will never return true, thus we will never attempt to query the custom attribute type for its
// own AttributeUsage custom attribute.) If the toolchain behavior changes in the future, it's preferable that
// this shows up as new MissingMetadataExceptions rather than incorrect results from the api so we will not put
// in an explicit return here.
}
}
Func <Type, bool> passesFilter;
if (optionalAttributeTypeFilter == null)
{
passesFilter =
delegate(Type actualType)
{
return(true);
};
}
else
{
passesFilter =
delegate(Type actualType)
{
if (optionalAttributeTypeFilter.Equals(actualType))
{
return(true);
}
if (typeFilterKnownToBeSealed)
{
return(false);
}
return(actualType.GetTypeInfo().IsSubclassOf(optionalAttributeTypeFilter));
};
}
return(GetMatchingCustomAttributesIterator(element, passesFilter, inherit));
}
public static bool IsSameOrSubClass(this TypeInfo subclass, TypeInfo baseclass) => subclass.IsSubclassOf(baseclass.AsType()) || subclass == baseclass;
