FrameworkPropertyMetadata Constructor (Object, FrameworkPropertyMetadataOptions, PropertyChangedCallback, CoerceValueCallback, Boolean, UpdateSourceTrigger)


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Initializes a new instance of the FrameworkPropertyMetadata class with the provided default value and framework metadata options, specified callbacks, a Boolean that can be used to prevent animation of the property, and a data-binding update trigger default.

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

Public Sub New (
	defaultValue As Object,
	flags As FrameworkPropertyMetadataOptions,
	propertyChangedCallback As PropertyChangedCallback,
	coerceValueCallback As CoerceValueCallback,
	isAnimationProhibited As Boolean,
	defaultUpdateSourceTrigger As UpdateSourceTrigger


Type: System.Object

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

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.

Type: System.Windows.PropertyChangedCallback

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

Type: System.Windows.CoerceValueCallback

A reference to a handler implementation that will be called whenever the property system calls CoerceValue against this property.

Type: System.Boolean

true to prevent the property system from animating the property that this metadata is applied to. Such properties will raise a run-time exception originating from the property system if animations of them are attempted. The default is false.

Type: System.Windows.Data.UpdateSourceTrigger

The UpdateSourceTrigger to use when bindings for this property are applied that have their UpdateSourceTrigger set to Default.

Exception Condition

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.

The isAnimationProhibited parameter sets the initial value of the IsAnimationProhibited property declared by the immediate base UIPropertyMetadata class.

For more information about the update source behavior for bindings, see Data Binding Overview.

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.

static FrameworkPropertyMetadata fpm;
fpm = new FrameworkPropertyMetadata(
    (FrameworkPropertyMetadataOptions.AffectsRender |
    new PropertyChangedCallback(OnCurrentReadingChanged),
    new CoerceValueCallback(CoerceCurrentReading),
    true //Animation prohibited
    , UpdateSourceTrigger.PropertyChanged

.NET Framework
Available since 3.0
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