FrameworkElement.ActualHeight Propiedad

public:
 property double ActualHeight { double get(); };

public double ActualHeight { get; }

member this.ActualHeight : double

Public ReadOnly Property ActualHeight As Double

Valor de propiedad

Alto del elemento, como un valor en unidades independientes del dispositivo (1/96 pulgadas por unidad). El valor predeterminado es 0 (cero).

Ejemplos

En el ejemplo siguiente se muestran varias propiedades de alto.

private void changeHeight(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    Double sz1 = Double.Parse(li.Content.ToString());
    rect1.Height = sz1;
    rect1.UpdateLayout();
    txt1.Text= "ActualHeight is set to " + rect1.ActualHeight;
    txt2.Text= "Height is set to " + rect1.Height;
    txt3.Text= "MinHeight is set to " + rect1.MinHeight;
    txt4.Text= "MaxHeight is set to " + rect1.MaxHeight;
}
private void changeMinHeight(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    Double sz1 = Double.Parse(li.Content.ToString());
    rect1.MinHeight = sz1;
    rect1.UpdateLayout();
    txt1.Text= "ActualHeight is set to " + rect1.ActualHeight;
    txt2.Text= "Height is set to " + rect1.Height;
    txt3.Text= "MinHeight is set to " + rect1.MinHeight;
    txt4.Text= "MaxHeight is set to " + rect1.MaxHeight;
}
private void changeMaxHeight(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    Double sz1 = Double.Parse(li.Content.ToString());
    rect1.MaxHeight = sz1;
    rect1.UpdateLayout();
    txt1.Text= "ActualHeight is set to " + rect1.ActualHeight;
    txt2.Text= "Height is set to " + rect1.Height;
    txt3.Text= "MinHeight is set to " + rect1.MinHeight;
    txt4.Text= "MaxHeight is set to " + rect1.MaxHeight;
}

Private Sub changeHeight(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)
    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim sz1 As Double = Double.Parse(li.Content.ToString())
    rect1.Height = sz1
    rect1.UpdateLayout()
    txt1.Text = "ActualHeight is set to " + rect1.ActualHeight.ToString
    txt2.Text = "Height is set to " + rect1.Height.ToString
    txt3.Text = "MinHeight is set to " + rect1.MinHeight.ToString
    txt4.Text = "MaxHeight is set to " + rect1.MaxHeight.ToString
End Sub
Private Sub changeMinHeight(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)

    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim sz1 As Double = Double.Parse(li.Content.ToString())
    rect1.MinHeight = sz1
    rect1.UpdateLayout()
    txt1.Text = "ActualHeight is set to " + rect1.ActualHeight.ToString
    txt2.Text = "Height is set to " + rect1.Height.ToString
    txt3.Text = "MinHeight is set to " + rect1.MinHeight.ToString
    txt4.Text = "MaxHeight is set to " + rect1.MaxHeight.ToString
End Sub
Private Sub changeMaxHeight(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)

    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim sz1 As Double = Double.Parse(li.Content.ToString())
    rect1.MaxHeight = sz1
    rect1.UpdateLayout()
    txt1.Text = "ActualHeight is set to " + rect1.ActualHeight.ToString
    txt2.Text = "Height is set to " + rect1.Height.ToString
    txt3.Text = "MinHeight is set to " + rect1.MinHeight.ToString
    txt4.Text = "MaxHeight is set to " + rect1.MaxHeight.ToString
End Sub

Comentarios

Esta propiedad es un valor calculado basado en otras entradas de alto y en el sistema de diseño. El propio sistema de diseño establece el valor basado en un pase de representación real y, por tanto, puede retardarse ligeramente detrás del valor establecido de propiedades, como Height que son la base del cambio de entrada.

Dado ActualHeight que es un valor calculado, debe tener en cuenta que podría haber varios cambios notificados o incrementales en él como resultado de varias operaciones por parte del sistema de diseño. El sistema de diseño puede calcular el espacio de medida necesario para los elementos secundarios, las restricciones del elemento primario, etc.

Aunque no puedes establecer esta propiedad desde XAML, puedes basar un elemento Trigger en su valor en un estilo.

Información de la propiedad dependency