The following code displays how to do custom drawing in a listbox.
using System.Windows.Forms;
using System.Drawing;
namespace Toolset.Controls
{
public class CustomDrawListBox : ListBox
{
public CustomDrawListBox()
{
this.DrawMode = DrawMode.OwnerDrawVariable; // We're using custom drawing.
this.ItemHeight = 40; // Set the item height to 40.
}
protected override void OnDrawItem(DrawItemEventArgs e)
{
// Make sure we're not trying to draw something that isn't there.
if (e.Index >= this.Items.Count || e.Index <= -1)
return;
// Get the item object.
object item = this.Items[e.Index];
if (item == null)
return;
// Draw the background color depending on
// if the item is selected or not.
if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
{
// The item is selected.
// We want a blue background color.
e.Graphics.FillRectangle(new SolidBrush(Color.Blue), e.Bounds);
}
else
{
// The item is NOT selected.
// We want a white background color.
e.Graphics.FillRectangle(new SolidBrush(Color.White), e.Bounds);
}
// Draw the item.
string text = item.ToString();
SizeF stringSize = e.Graphics.MeasureString(text, this.Font);
e.Graphics.DrawString(text, this.Font, new SolidBrush(Color.White),
new PointF(5, e.Bounds.Y + (e.Bounds.Height - stringSize.Height) / 2));
}
}
}
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