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ScrollableControl.AutoScrollPosition Property

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Gets or sets the location of the auto-scroll position.

public:
 property System::Drawing::Point AutoScrollPosition { System::Drawing::Point get(); void set(System::Drawing::Point value); };
[System.ComponentModel.Browsable(false)]
public System.Drawing.Point AutoScrollPosition { get; set; }
[<System.ComponentModel.Browsable(false)>]
member this.AutoScrollPosition : System.Drawing.Point with get, set
Public Property AutoScrollPosition As Point

Property Value

Point

A Point that represents the auto-scroll position in pixels.

Attributes
BrowsableAttribute

Examples

The following code example uses the ScrollableControl derived class Panel and adds a button to the upper left corner of the scrollable area. The example allows for the offset determined by the AutoScrollPosition. The example was written under the assumption that you have a Form that contains a Panel with a Button on it. To enable auto-scrolling, place the button outside of the client area of the Panel.

private:
   void button1_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      /* Add a button to top left corner of the
            * scrollable area, allowing for the offset. */
      panel1->AutoScroll = true;
      Button^ myButton = gcnew Button;
      myButton->Location = Point(0 + panel1->AutoScrollPosition.X,0 + panel1->AutoScrollPosition.Y);
      panel1->Controls->Add( myButton );
   }

private void button1_Click(object sender, EventArgs e)
{
   /* Add a button to top left corner of the 
    * scrollable area, allowing for the offset. */
   panel1.AutoScroll = true;
   Button myButton = new Button();
   myButton.Location = new Point(
      0 + panel1.AutoScrollPosition.X, 
      0 + panel1.AutoScrollPosition.Y);
   panel1.Controls.Add(myButton);
}

Private Sub button1_Click(sender As Object, _
   e As EventArgs) Handles button1.Click
   ' Add a button to top left corner of the 
   ' scrollable area, allowing for the offset. 
   panel1.AutoScroll = True
   Dim myButton As New Button()
   myButton.Location = New Point( _
      0 + panel1.AutoScrollPosition.X, _
      0 + panel1.AutoScrollPosition.Y)
   panel1.Controls.Add(myButton)
End Sub

Remarks

The AutoScrollPosition property represents the location of the visible portion of a scrollable control. Use this property to change the portion of the control that is displayed.

When adding controls programmatically to a form, use the AutoScrollPosition property to position the control either inside or outside of the current viewable scroll area.

Note

The X and Y coordinate values retrieved are negative if the control has scrolled away from its starting position (0,0). When you set this property, you must always assign positive X and Y values to set the scroll position relative to the starting position. For example, if you have a horizontal scroll bar and you set x and y to 200, you move the scroll 200 pixels to the right; if you then set x and y to 100, the scroll appears to jump the left by 100 pixels, because you are setting it 100 pixels away from the starting position. In the first case, AutoScrollPosition returns {-200, 0}; in the second case, it returns {-100,0}.

To detect when AutoScrollPosition changes, create an event handler for the Paint event, save the old position value in a private variable, and compare the new value to the old value on subsequent Paint events.

Applies to

See also