private void SetupOverrideMetadata(Type forType, PropertyMetadata typeMetadata, out DependencyObjectType dType, out PropertyMetadata baseMetadata)
{
if (forType == null)
{
throw new ArgumentNullException("forType");
}
if (typeMetadata == null)
{
throw new ArgumentNullException("typeMetadata");
}
if (typeMetadata.Sealed)
{
throw new ArgumentException(SR.Get("TypeMetadataAlreadyInUse"));
}
if (!typeof(DependencyObject).IsAssignableFrom(forType))
{
throw new ArgumentException(SR.Get("TypeMustBeDependencyObjectDerived", forType.Name));
}
if (typeMetadata.IsDefaultValueModified)
{
ValidateMetadataDefaultValue(typeMetadata, PropertyType, Name, ValidateValueCallback);
}
dType = DependencyObjectType.FromSystemType(forType);
baseMetadata = GetMetadata(dType.BaseType);
if (!baseMetadata.GetType().IsAssignableFrom(typeMetadata.GetType()))
{
throw new ArgumentException(SR.Get("OverridingMetadataDoesNotMatchBaseMetadataType"));
}
}
/// <summary>Returns the metadata for this dependency property as it exists on a specified existing type. </summary>
/// <returns>A property metadata object.</returns>
/// <param name="forType">The specific type from which to retrieve the dependency property metadata.</param>
public PropertyMetadata GetMetadata(Type forType)
{
if (forType != null)
{
return(GetMetadata(DependencyObjectType.FromSystemType(forType)));
}
throw new ArgumentNullException("forType");
}
/// <summary>
/// Parameter validation for OverrideMetadata, includes code to force
/// all base classes of "forType" to register their metadata so we know
/// what we are overriding.
/// </summary>
private void SetupOverrideMetadata(
Type forType,
PropertyMetadata typeMetadata,
out DependencyObjectType dType,
out PropertyMetadata baseMetadata)
{
if (forType == null)
{
throw new ArgumentNullException("forType");
}
if (typeMetadata == null)
{
throw new ArgumentNullException("typeMetadata");
}
if (typeMetadata.Sealed)
{
throw new ArgumentException(SR.TypeMetadataAlreadyInUse);
}
if (!typeof(DependencyObject).IsAssignableFrom(forType))
{
throw new ArgumentException(SR.Format(SR.TypeMustBeDependencyObjectDerived, forType.Name));
}
// Ensure default value is a correct value (if it was supplied,
// otherwise, the default value will be taken from the base metadata
// which was already validated)
if (typeMetadata.IsDefaultValueModified)
{
// Will throw ArgumentException if fails.
ValidateMetadataDefaultValue(typeMetadata, PropertyType, Name, ValidateValueCallback);
}
// Force all base classes to register their metadata
dType = DependencyObjectType.FromSystemType(forType);
// Get metadata for the base type
baseMetadata = GetMetadata(dType.BaseType);
// Make sure overriding metadata is the same type or derived type of
// the base metadata
if (!baseMetadata.GetType().IsAssignableFrom(typeMetadata.GetType()))
{
throw new ArgumentException(SR.OverridingMetadataDoesNotMatchBaseMetadataType);
}
}
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
/// <summary>
/// Returns true if the dependency object passed to the method is a type,
/// subtype or implememts the interface of any of the the types contained
/// in this object.
/// </summary>
internal override bool IsBrowsable(DependencyObject d, DependencyProperty dp)
{
if (d == null)
{
throw new ArgumentNullException("d");
}
if (dp == null)
{
throw new ArgumentNullException("dp");
}
// Get the dependency object type for our target type.
// We cannot assume the user didn't do something wrong and
// feed us a type that is not a dependency object, but that is
// rare enough that it is worth the try/catch here rather than
// a double IsAssignableFrom (one here, and one in DependencyObjectType).
// We still use a flag here rather than checking for a null
// _dTargetType so that a bad property that throws won't consistently
// slow the system down with ArgumentExceptions.
if (!_dTargetTypeChecked)
{
try
{
_dTargetType = DependencyObjectType.FromSystemType(_targetType);
}
catch (ArgumentException)
{
}
_dTargetTypeChecked = true;
}
if (_dTargetType != null && _dTargetType.IsInstanceOfType(d))
{
return(true);
}
return(false);
}
