windowsforms-devexpress-dot-xtraeditors-9f23520a.md
The vertical scrollbar.
Namespace : DevExpress.XtraEditors
Assembly : DevExpress.Utils.v25.2.dll
NuGet Packages : DevExpress.Utils, DevExpress.Wpf.Core
public class VScrollBar :
VScrollBarBase,
ISupportXtraAnimation,
IScrollBarWithAnnotations
Public Class VScrollBar
Inherits VScrollBarBase
Implements ISupportXtraAnimation,
IScrollBarWithAnnotations
The following members return VScrollBar objects:
Most controls (such as ListBoxControl, ImageListBoxControl, etc) that need scroll bars already provide them and do not require this control.
You can, however, use this control to implement vertical scrolling in containers that do not provide their own scroll bars, as shown in the example below. Properies inherited from the ScrollBarBase class allow you to specify the lower and upper limits of the scrollable range, the scroll box’s current position, etc.
The following sample code uses both HScrollBar and VScrollBar controls to provide easy navigation through an image displayed within the pictureBox control if image dimensions extend the dimensions of the picture box. The Paint picture box event is handled to draw a specific image region specified by the position of the scroll bar to the screen. The x and y variables correspondingly represent the x- and y-coordinate of the upper-left corner of the portion of the image to draw in the picture box. The ScrollBarBase.Scroll events are used, in turn, to define the coordinates of the upper-left corner of the image portion according to scroll bar position after the user has scrolled either one or both scroll bars.
using DevExpress.XtraEditors;
private void Form1_Load(object sender, System.EventArgs e) {
hScrollBar1.Width = pictureBox1.Width;
hScrollBar1.Left = pictureBox1.Left;
hScrollBar1.Top = pictureBox1.Bottom;
hScrollBar1.Maximum = pictureBox1.Image.Width - pictureBox1.Width;
vScrollBar1.Height = pictureBox1.Height;
vScrollBar1.Left = pictureBox1.Left + pictureBox1.Width;
vScrollBar1.Top = pictureBox1.Top;
vScrollBar1.Maximum = pictureBox1.Image.Height - pictureBox1.Height;
}
int x = 0;
private void hScrollBar1_Scroll(object sender, System.Windows.Forms.ScrollEventArgs e) {
x = (sender as HScrollBar).Value;
pictureBox1.Refresh();
}
int y = 0;
private void vScrollBar1_Scroll(object sender, System.Windows.Forms.ScrollEventArgs e) {
y = (sender as VScrollBar).Value;
pictureBox1.Refresh();
}
private void pictureBox1_Paint(object sender, System.Windows.Forms.PaintEventArgs e) {
pBox = sender as PictureBox;
e.Graphics.DrawImage(pBox.Image, e.ClipRectangle, x, y, e.ClipRectangle.Width,
e.ClipRectangle.Height, GraphicsUnit.Pixel);
}
Imports DevExpress.XtraEditors
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs)
hScrollBar1.Width = pictureBox1.Width
hScrollBar1.Left = pictureBox1.Left
hScrollBar1.Top = pictureBox1.Bottom
hScrollBar1.Maximum = pictureBox1.Image.Width - pictureBox1.Width
vScrollBar1.Height = pictureBox1.Height
vScrollBar1.Left = pictureBox1.Left + pictureBox1.Width
vScrollBar1.Top = pictureBox1.Top
vScrollBar1.Maximum = pictureBox1.Image.Height - pictureBox1.Height
End Sub
Private x As Integer = 0
Private Sub hScrollBar1_Scroll(ByVal sender As Object, ByVal e As System.Windows.Forms.ScrollEventArgs)
x = (TryCast(sender, HScrollBar)).Value
pictureBox1.Refresh()
End Sub
Private y As Integer = 0
Private Sub vScrollBar1_Scroll(ByVal sender As Object, ByVal e As System.Windows.Forms.ScrollEventArgs)
y = (TryCast(sender, VScrollBar)).Value
pictureBox1.Refresh()
End Sub
Private Sub pictureBox1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs)
pBox = TryCast(sender, PictureBox)
e.Graphics.DrawImage(pBox.Image, e.ClipRectangle, x, y, e.ClipRectangle.Width, e.ClipRectangle.Height, GraphicsUnit.Pixel)
End Sub
Object MarshalByRefObject Component Control DevExpress.XtraEditors.XtraControl ScrollBarBase DevExpress.XtraEditors.ScrollTouchBase VScrollBarBase VScrollBar
See Also
VScrollBar