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DependencyObject.SetValue Method

Definition

Sets the local value of a dependency property.

Overloads

SetValue(DependencyProperty, Object)

Sets the local value of a dependency property, specified by its dependency property identifier.

SetValue(DependencyPropertyKey, Object)

Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property.

SetValue(DependencyProperty, Object)

Sets the local value of a dependency property, specified by its dependency property identifier.

public:
 void SetValue(System::Windows::DependencyProperty ^ dp, System::Object ^ value);
public void SetValue (System.Windows.DependencyProperty dp, object value);
member this.SetValue : System.Windows.DependencyProperty * obj -> unit
Public Sub SetValue (dp As DependencyProperty, value As Object)

Parameters

dp
DependencyProperty

The identifier of the dependency property to set.

value
Object

The new local value.

Exceptions

Attempted to modify a read-only dependency property, or a property on a sealed DependencyObject.

value was not the correct type as registered for the dp property.

Remarks

If the provided type does not match the type that is declared for the dependency property as it was originally registered, an exception is thrown. The value parameter should always be provided as the appropriate type.

The exception conditions are potentially influenced by the ValidateValueCallback callback that exists on the dependency property identifier of the dependency property being set. Otherwise, the value provided might be failing general type-checking conditions (for example, passing a string when the native type is Double).

Applies to

SetValue(DependencyPropertyKey, Object)

Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property.

public:
 void SetValue(System::Windows::DependencyPropertyKey ^ key, System::Object ^ value);
public void SetValue (System.Windows.DependencyPropertyKey key, object value);
member this.SetValue : System.Windows.DependencyPropertyKey * obj -> unit
Public Sub SetValue (key As DependencyPropertyKey, value As Object)

Parameters

key
DependencyPropertyKey

The DependencyPropertyKey identifier of the property to set.

value
Object

The new local value.

Examples

The following example defines a read-only dependency property, along with a public static readonly DependencyProperty that provides necessary read-only exposure to property consumers, and the get accessor for the CLR wrapper.

internal static readonly DependencyPropertyKey AquariumSizeKey = DependencyProperty.RegisterReadOnly(
  "AquariumSize",
  typeof(double),
  typeof(Aquarium),
  new PropertyMetadata(double.NaN)
);
public static readonly DependencyProperty AquariumSizeProperty =
  AquariumSizeKey.DependencyProperty;
public double AquariumSize
{
  get { return (double)GetValue(AquariumSizeProperty); }
}
Friend Shared ReadOnly AquariumSizeKey As DependencyPropertyKey = DependencyProperty.RegisterReadOnly("AquariumSize", GetType(Double), GetType(Aquarium), New PropertyMetadata(Double.NaN))
Public Shared ReadOnly AquariumSizeProperty As DependencyProperty = AquariumSizeKey.DependencyProperty
Public ReadOnly Property AquariumSize() As Double
    Get
        Return CDbl(GetValue(AquariumSizeProperty))
    End Get
End Property

Remarks

This signature is generally used when you set values for read-only dependency properties that are defined by your custom classes. Generally, SetValue is called only from the type that registered that dependency property, which implements the internal logic that provides the determined value for the dependency property. For more information, see Read-Only Dependency Properties.

If the provided type does not match the type that is declared for the dependency property as it was originally registered, an exception is thrown. The value parameter should always be provided as the appropriate type. The exception conditions are potentially influenced by the ValidateValueCallback callback that exists on the dependency property identifier of the dependency property being set.

Applies to