/// <summary>
/// This method returns an extended custom type descriptor for the given object.
/// An extended type descriptor is a custom type descriptor that offers properties
/// that other objects have added to this object, but are not actually defined on
/// the object. For example, in the .NET Framework Component Model, objects that
/// implement the interface IExtenderProvider can "attach" properties to other
/// objects that reside in the same logical container. The GetTypeDescriptor
/// method does not return a type descriptor that provides these extra extended
/// properties. GetExtendedTypeDescriptor returns the set of these extended
/// properties. TypeDescriptor will automatically merge the results of these
/// two property collections. Note that while the .NET Framework component
/// model only supports extended properties this API can be used for extended
/// attributes and events as well, if the type description provider supports it.
/// </summary>
public virtual ICustomTypeDescriptor GetExtendedTypeDescriptor(object instance)
{
if (_parent != null)
{
return(_parent.GetExtendedTypeDescriptor(instance));
}
return(_emptyDescriptor ?? (_emptyDescriptor = new EmptyCustomTypeDescriptor()));
}
/// <summary>
/// This method returns a custom type descriptor for the given type / object.
/// The objectType parameter is always valid, but the instance parameter may
/// be null if no instance was passed to TypeDescriptor. The method should
/// return a custom type descriptor for the object. If the method is not
/// interested in providing type information for the object it should
/// return base.
///
/// This method is prototyped as virtual, and by default returns a
/// custom type descriptor that returns empty collections for all values
/// if no parent provider was passed. If a parent provider was passed,
/// this method will invoke the parent provider's GetTypeDescriptor
/// method.
/// </summary>
public virtual ICustomTypeDescriptor GetTypeDescriptor([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type objectType, object instance)
{
if (_parent != null)
{
return(_parent.GetTypeDescriptor(objectType, instance));
}
return(_emptyDescriptor ?? (_emptyDescriptor = new EmptyCustomTypeDescriptor()));
}
public virtual ICustomTypeDescriptor GetExtendedTypeDescriptor (object instance)
{
if (_parent != null)
return _parent.GetExtendedTypeDescriptor (instance);
if (_emptyCustomTypeDescriptor == null)
_emptyCustomTypeDescriptor = new EmptyCustomTypeDescriptor ();
return _emptyCustomTypeDescriptor;
}
/// <summary>Gets a custom type descriptor for the given type and object.</summary>
/// <returns>An <see cref="T:System.ComponentModel.ICustomTypeDescriptor" /> that can provide metadata for the type.</returns>
/// <param name="objectType">The type of object for which to retrieve the type descriptor.</param>
/// <param name="instance">An instance of the type. Can be null if no instance was passed to the <see cref="T:System.ComponentModel.TypeDescriptor" />.</param>
public virtual ICustomTypeDescriptor GetTypeDescriptor(Type objectType, object instance)
{
if (_parent != null)
{
return(_parent.GetTypeDescriptor(objectType, instance));
}
if (_emptyCustomTypeDescriptor == null)
{
_emptyCustomTypeDescriptor = new EmptyCustomTypeDescriptor();
}
return(_emptyCustomTypeDescriptor);
}
public virtual ICustomTypeDescriptor GetExtendedTypeDescriptor(object instance)
{
if (this._parent != null)
{
return(this._parent.GetExtendedTypeDescriptor(instance));
}
if (this._emptyDescriptor == null)
{
this._emptyDescriptor = new EmptyCustomTypeDescriptor();
}
return(this._emptyDescriptor);
}
/// <devdoc>
/// This method returns a custom type descriptor for the given type / object.
/// The objectType parameter is always valid, but the instance parameter may
/// be null if no instance was passed to TypeDescriptor. The method should
/// return a custom type descriptor for the object. If the method is not
/// interested in providing type information for the object it should
/// return base.
///
/// This method is prototyped as virtual, and by default returns a
/// custom type descriptor that returns empty collections for all values
/// if no parent provider was passed. If a parent provider was passed,
/// this method will invoke the parent provider's GetTypeDescriptor
/// method.
/// </devdoc>
public virtual ICustomTypeDescriptor GetTypeDescriptor(Type objectType, object instance)
{
if (_parent != null)
{
return _parent.GetTypeDescriptor(objectType, instance);
}
if (_emptyDescriptor == null) {
_emptyDescriptor = new EmptyCustomTypeDescriptor();
}
return _emptyDescriptor;
}
/// <summary>
/// This method returns an extended custom type descriptor for the given object.
/// An extended type descriptor is a custom type descriptor that offers properties
/// that other objects have added to this object, but are not actually defined on
/// the object. For example, in the .NET Framework Component Model, objects that
/// implement the interface IExtenderProvider can "attach" properties to other
/// objects that reside in the same logical container. The GetTypeDescriptor
/// method does not return a type descriptor that provides these extra extended
/// properties. GetExtendedTypeDescriptor returns the set of these extended
/// properties. TypeDescriptor will automatically merge the results of these
/// two property collections. Note that while the .NET Framework component
/// model only supports extended properties this API can be used for extended
/// attributes and events as well, if the type description provider supports it.
/// </summary>
public virtual ICustomTypeDescriptor GetExtendedTypeDescriptor(object instance)
{
if (_parent != null)
{
return _parent.GetExtendedTypeDescriptor(instance);
}
return _emptyDescriptor ?? (_emptyDescriptor = new EmptyCustomTypeDescriptor());
}
