DrawingVisual.Drawing Propriété

Définition

Espace de noms:

System.Windows.Media

Assembly:

PresentationCore.dll

Obtient le contenu de dessin de l'objet DrawingVisual.

public:
 property System::Windows::Media::DrawingGroup ^ Drawing { System::Windows::Media::DrawingGroup ^ get(); };

public System.Windows.Media.DrawingGroup Drawing { get; }

member this.Drawing : System.Windows.Media.DrawingGroup

Public ReadOnly Property Drawing As DrawingGroup

Valeur de propriété

DrawingGroup

Obtient une valeur de type DrawingGroup qui représente la collection d'objets Drawing dans le DrawingVisual.

Exemples

Dans l’exemple suivant, la DrawingGroup valeur de chacun DrawingVisual d’un visuel hôte est énumérée.

// Enumerate the DrawingVisual children of a host visual.
public void RetrieveDrawings(Visual visualHost)
{
    for (int i = 0; i < VisualTreeHelper.GetChildrenCount(visualHost); i++)
    {
        // Retrieve child visual at specified index value.
        DependencyObject dependencyObject = VisualTreeHelper.GetChild(visualHost, i);

        // Determine if the child object is a DrawingVisual.
        if (dependencyObject.GetType() == typeof(DrawingVisual))
        {
            DrawingVisual drawingVisual = (DrawingVisual)dependencyObject;

            if (drawingVisual.Drawing != null)
            {
                if (drawingVisual.Drawing.GetType() == typeof(DrawingGroup))
                {
                    // Enumerate the drawings in the DrawingGroup.
                    EnumDrawingGroup(drawingVisual.Drawing);
                }
            }
        }
     }
 }

 // Enumerate the drawings in the DrawingGroup.
 public void EnumDrawingGroup(DrawingGroup drawingGroup)
 {
     DrawingCollection dc = drawingGroup.Children;

     // Enumerate the drawings in the DrawingCollection.
     foreach (Drawing drawing in dc)
     {
         // If the drawing is a DrawingGroup, call the function recursively.
         if (drawing.GetType() == typeof(DrawingGroup))
         {
             EnumDrawingGroup((DrawingGroup)drawing);
         }

         if (drawing.GetType() == typeof(GeometryDrawing))
         {
             // Perform action based on drawing type.
         }
     }
 }

' Enumerate the DrawingVisual children of a host visual.
Public Sub RetrieveDrawings(ByVal visualHost As Visual)
    For i As Integer = 0 To VisualTreeHelper.GetChildrenCount(visualHost) - 1
        ' Retrieve child visual at specified index value.
        Dim dependencyObject As DependencyObject = VisualTreeHelper.GetChild(visualHost, i)

        ' Determine if the child object is a DrawingVisual.
        If dependencyObject.GetType() Is GetType(DrawingVisual) Then
            Dim drawingVisual As DrawingVisual = CType(dependencyObject, DrawingVisual)

            If drawingVisual.Drawing IsNot Nothing Then
                If drawingVisual.Drawing.GetType() Is GetType(DrawingGroup) Then
                    ' Enumerate the drawings in the DrawingGroup.
                    EnumDrawingGroup(drawingVisual.Drawing)
                End If
            End If
        End If
    Next i
End Sub

 ' Enumerate the drawings in the DrawingGroup.
 Public Sub EnumDrawingGroup(ByVal drawingGroup As DrawingGroup)
     Dim dc As DrawingCollection = drawingGroup.Children

     ' Enumerate the drawings in the DrawingCollection.
     For Each drawing As Drawing In dc
         ' If the drawing is a DrawingGroup, call the function recursively.
         If drawing.GetType() Is GetType(DrawingGroup) Then
             EnumDrawingGroup(CType(drawing, DrawingGroup))
         End If

         If drawing.GetType() Is GetType(GeometryDrawing) Then
             ' Perform action based on drawing type.
         End If
     Next drawing
 End Sub

Remarques

Un objet visuel stocke ses données de rendu en tant que liste d’instructions graphiques vectorielles. Chaque élément de la liste d’instructions représente un ensemble de données graphiques de bas niveau dans un format sérialisé. Pour plus d’informations sur la façon dont les objets visuels stockent des données graphiques, consultez vue d’ensemble du rendu graphique WPF.

Toute modification apportée à la valeur retournée DrawingGroup n’est pas conservée par le DrawingVisual.