How to change ListBox selection background color?

The below code does exactly what you are saying:

In the InitializeComponent method:

this.listBox1.DrawMode = DrawMode.OwnerDrawFixed;
this.listBox1.DrawItem += new System.Windows.Forms.DrawItemEventHandler(listBox1_DrawItem);
this.listBox1.SelectedIndexChanged += new System.EventHandler(listBox1_SelectedIndexChanged);

And the event handlers:

void listBox1_SelectedIndexChanged(object sender, System.EventArgs e)
{
    this.listBox1.Invalidate();
}

void listBox1_DrawItem(object sender, System.Windows.Forms.DrawItemEventArgs e)
{
    int index = e.Index;
    Graphics g = e.Graphics;
    foreach (int selectedIndex in this.listBox1.SelectedIndices)
    {
        if (index == selectedIndex)
        {
            // Draw the new background colour
            e.DrawBackground();
            g.FillRectangle(new SolidBrush(Color.Red), e.Bounds);
        }
    }

    // Get the item details
    Font font = listBox1.Font;
    Color colour = listBox1.ForeColor;
    string text = listBox1.Items[index].ToString();

    // Print the text
    g.DrawString(text, font, new SolidBrush(Color.Black), (float)e.Bounds.X, (float)e.Bounds.Y);
    e.DrawFocusRectangle();
}

Code is taken from:

http://www.weask.us/entry/change-listbox-rsquo-selected-item-backcolor-net

Hopefully this will help someone in the future as the above code helped me but not 100%

I still had the following problems:
- when i selected another index, the newly selected index would also highlight red.
- when i changed the font size of the listbox, the highlighted area would be to small.

Below fixes that problem

• change the DrawMode to ownerdrawvariable
• create a MeasurItem and DrawItem event for the listbox

private void lstCartOutput_MeasureItem(object sender, MeasureItemEventArgs e)
{
   // Cast the sender object back to ListBox type.
   ListBox listBox = (ListBox)sender;
   e.ItemHeight = listBox.Font.Height;
}

private void lstCartOutput_DrawItem(object sender, DrawItemEventArgs e)
{
   ListBox listBox = (ListBox)sender;
   e.DrawBackground();
   Brush myBrush = Brushes.Black;

   if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
   {
      myBrush = Brushes.Red;
      e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(0, 64, 64)), e.Bounds);
   }

   else
   {
      e.Graphics.FillRectangle(Brushes.White, e.Bounds);

   }

   e.Graphics.DrawString(listBox.Items[e.Index].ToString(),e.Font, myBrush, e.Bounds);
   e.DrawFocusRectangle();
}

I also referenced the MSDN website.

You must override the Drawitem event and set the DrawMode property to DrawMode.OwnerDrawFixed

check this sample

private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
{
    if (e.Index<0) return;
    //if the item state is selected them change the back color 
    if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
        e = new DrawItemEventArgs(e.Graphics, 
                                  e.Font, 
                                  e.Bounds, 
                                  e.Index,
                                  e.State ^ DrawItemState.Selected,
                                  e.ForeColor, 
                                  Color.Yellow);//Choose the color

    // Draw the background of the ListBox control for each item.
    e.DrawBackground();
    // Draw the current item text
    e.Graphics.DrawString(listBox1.Items[e.Index].ToString(),e.Font, Brushes.Black, e.Bounds, StringFormat.GenericDefault);
    // If the ListBox has focus, draw a focus rectangle around the selected item.
    e.DrawFocusRectangle();
}