Occurs during drawing before the objects are drawn.

Syntax

Visual Basic (Declaration)
Public Event BeforeDrawingObjects() As EventHandler(Of AnnPaintEventArgs)

Visual Basic (Usage)	Copy Code
`Dim instance As AnnContainer Dim handler As EventHandler(Of AnnPaintEventArgs) AddHandler instance.BeforeDrawingObjects, handler`

C#
public event EventHandler<AnnPaintEventArgs> BeforeDrawingObjects()

C++/CLI
public: event EventHandler<AnnPaintEventArgs>^ BeforeDrawingObjects();

Example

This example will draw a grid 100 pixels apart on the surface of the viewer before the container is drawn.

Visual Basic Copy Code

Visual Basic	Copy Code
Public theContainer As AnnContainer Public Sub AnnContainer_BeforeDrawingObjects(ByVal container As AnnContainer) ' theContainer is set so that it can be accessed in the container_BeforeDrawingObjects event theContainer = container AddHandler container.BeforeDrawingObjects, AddressOf container_BeforeDrawingObjects End Sub Private Sub container_BeforeDrawingObjects(ByVal sender As Object, ByVal e As AnnPaintEventArgs) ' draw a grid, 100 pixels apart Dim graphics As Graphics = e.Graphics ' set the current transform from the container graphics.MultiplyTransform(theContainer.Transform) ' get the bounds in pixels Dim rc As AnnRectangle = theContainer.Bounds.ConvertTo(theContainer.UnitConverter, AnnUnit.Pixel) Dim p As Pen = New Pen(Color.FromArgb(128, 255, 255, 255)) Try ' draw the grid Dim x As Single = rc.Left Do While x <= rc.Right graphics.DrawLine(p, x, 0, x, rc.Bottom) x += 100 Loop Dim y As Single = rc.Top Do While y <= rc.Bottom graphics.DrawLine(p, 0, y, rc.Right, y) y += 100 Loop Finally CType(p, IDisposable).Dispose() End Try End Sub

Public theContainer As AnnContainer

Public Sub AnnContainer_BeforeDrawingObjects(ByVal container As AnnContainer)

   ' theContainer is set so that it can be accessed in the container_BeforeDrawingObjects event

   theContainer = container

   AddHandler container.BeforeDrawingObjects, AddressOf container_BeforeDrawingObjects

End Sub

Private Sub container_BeforeDrawingObjects(ByVal sender As Object, ByVal e As AnnPaintEventArgs)

   ' draw a grid, 100 pixels apart



   Dim graphics As Graphics = e.Graphics



   ' set the current transform from the container

   graphics.MultiplyTransform(theContainer.Transform)



   ' get the bounds in pixels

   Dim rc As AnnRectangle = theContainer.Bounds.ConvertTo(theContainer.UnitConverter, AnnUnit.Pixel)



   Dim p As Pen = New Pen(Color.FromArgb(128, 255, 255, 255))

   Try

      ' draw the grid

      Dim x As Single = rc.Left

      Do While x <= rc.Right

         graphics.DrawLine(p, x, 0, x, rc.Bottom)

         x += 100

      Loop



      Dim y As Single = rc.Top

      Do While y <= rc.Bottom

         graphics.DrawLine(p, 0, y, rc.Right, y)

         y += 100

      Loop

   Finally

      CType(p, IDisposable).Dispose()

   End Try

End Sub

C# Copy Code

C#	Copy Code
public AnnContainer theContainer; public void AnnContainer_BeforeDrawingObjects(AnnContainer container) { // theContainer is set so that it can be accessed in the container_BeforeDrawingObjects event theContainer = container; container.BeforeDrawingObjects += new EventHandler<AnnPaintEventArgs>(container_BeforeDrawingObjects); } private void container_BeforeDrawingObjects(object sender, AnnPaintEventArgs e) { // draw a grid, 100 pixels apart Graphics graphics = e.Graphics; // set the current transform from the container graphics.MultiplyTransform(theContainer.Transform); // get the bounds in pixels AnnRectangle rc = theContainer.Bounds.ConvertTo(theContainer.UnitConverter, AnnUnit.Pixel); using (Pen p = new Pen(Color.FromArgb(128, 255, 255, 255))) { // draw the grid for (float x = rc.Left; x <= rc.Right; x += 100) graphics.DrawLine(p, x, 0, x, rc.Bottom); for (float y = rc.Top; y <= rc.Bottom; y += 100) graphics.DrawLine(p, 0, y, rc.Right, y); } }

public AnnContainer theContainer; 
public void AnnContainer_BeforeDrawingObjects(AnnContainer container) 
{ 
   // theContainer is set so that it can be accessed in the container_BeforeDrawingObjects event 
   theContainer = container; 
   container.BeforeDrawingObjects += new EventHandler<AnnPaintEventArgs>(container_BeforeDrawingObjects); 
} 
private void container_BeforeDrawingObjects(object sender, AnnPaintEventArgs e) 
{ 
   // draw a grid, 100 pixels apart 
 
   Graphics graphics = e.Graphics; 
 
   // set the current transform from the container 
   graphics.MultiplyTransform(theContainer.Transform); 
 
   // get the bounds in pixels 
   AnnRectangle rc = theContainer.Bounds.ConvertTo(theContainer.UnitConverter, AnnUnit.Pixel); 
 
   using (Pen p = new Pen(Color.FromArgb(128, 255, 255, 255))) 
   { 
      // draw the grid 
      for (float x = rc.Left; x <= rc.Right; x += 100) 
         graphics.DrawLine(p, x, 0, x, rc.Bottom); 
 
      for (float y = rc.Top; y <= rc.Bottom; y += 100) 
         graphics.DrawLine(p, 0, y, rc.Right, y); 
   } 
}

Remarks

You can prevent the AnnContainer from raising this event by calling DisableDrawObjectEvents. You can re-enable the raising of this event by calling EnableDrawObjectEvents.

Requirements

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

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BeforeDrawingObjects Event
See Also Example

Syntax

Example

Remarks

Requirements

See Also

Reference