FrameworkPropertyMetadata Constructor (Object, FrameworkPropertyMetadataOptions, PropertyChangedCallback)

Initializes a new instance of the FrameworkPropertyMetadata class with the provided default value and framework metadata options, and specified PropertyChangedCallback callback.

Namespace:  System.Windows
Assembly:  PresentationFramework (in PresentationFramework.dll)

'Declaration
Public Sub New ( _
	defaultValue As Object, _
	flags As FrameworkPropertyMetadataOptions, _
	propertyChangedCallback As PropertyChangedCallback _
)

Parameters

defaultValue
Type: System.Object

The default value of the dependency property, usually provided as a value of a specific type.

flags
Type: System.Windows.FrameworkPropertyMetadataOptions

The metadata option flags (a combination of FrameworkPropertyMetadataOptions values). These options specify characteristics of the dependency property that interact with systems such as layout or data binding.

propertyChangedCallback
Type: System.Windows.PropertyChangedCallback

A reference to a handler implementation that the property system will call whenever the effective value of the property changes.

ExceptionCondition
ArgumentException

defaultValue is set to UnsetValue; see Remarks.

The type of the value provided for defaultValue must match or be related to the type specified in the original registration of the dependency property that this metadata will be applied to. Mismatches between metadata default value type and the type of the dependency property it is being applied to can be difficult to debug, because the mismatch is not detectable during compilation. The property system does not evaluate the effective value of a property until run time, so the result of a default value type/property type mismatch is a run-time error.

The value UnsetValue has special meaning in the property system, and cannot be used as a dependency property default value.

Values marked as set flags in the flags parameter will set the Boolean value of FrameworkPropertyMetadata properties that match that FrameworkPropertyMetadataOptions flag's name to true. You can still change the values of the properties in the metadata, as long as the metadata has not yet been applied to a specific property system operation.

The following example calls this constructor signature:

static FrameworkPropertyMetadata fpm;


...


fpm = new FrameworkPropertyMetadata(
    Double.NaN,
    (FrameworkPropertyMetadataOptions.AffectsRender |
      FrameworkPropertyMetadataOptions.BindsTwoWayByDefault),
    new PropertyChangedCallback(OnCurrentReadingChanged)
);

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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