C# make specific ListBox item text bold and remove some items

How do I remove the "red marked" area and make the "blue marked" area bold in my listbox?
And I would like to have two empty items between the item MAT and LBL1. How do I make it possible?

I tryed:
No idea how.. but try to bold it...

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
        ListBox1.DrawMode = DrawMode.OwnerDrawFixed;
    }

    private void ListBox1_DrawItem(object sender, DrawItemEventArgs e)
    {
        ListBox lb1 = (ListBox)sender;
        var itemText = lb1.Items[e.Index].ToString();
        var textBold = FontStyle.Bold;

        // Make index bold from Client to MAT(or Client to first empty item)

        e.DrawBackground();
        e.Graphics.DrawString(ListBox1.Items[e.Index].ToString(), new Font("Arial", 10, FontStyle.Bold), Brushes.Black, e.Bounds);
        e.DrawFocusRectangle();
    }
}

I actually found a solution. Delete some items and make some bold. It works fine!

> void document_PrintPage(object sender, PrintPageEventArgs e)
> {
> e.Graphics.PageUnit = GraphicsUnit.Millimeter;
> int leading = 1;
> int leftMargin = 25;
> int topMargin = 25;
>
> // a few simple formatting options..
> StringFormat FmtRight = new StringFormat() { Alignment = StringAlignment.Far };
> StringFormat FmtLeft = new StringFormat() { Alignment = StringAlignment.Near };
> StringFormat FmtCenter = new StringFormat() { Alignment = StringAlignment.Near };
>
> StringFormat fmt = FmtLeft;
>
> //set bold for the first 6 lines
> using (Font font = new Font("Arial", 12f, FontStyle.Bold))
> {
> SizeF sz = e.Graphics.MeasureString("|", Font);
> float h = sz.Height + leading;
>
> for (int i = 0; i < 6; i++)
> e.Graphics.DrawString(listBox9.Items[i].ToString(), font,
> Brushes.Black, leftMargin, topMargin + h * i, fmt);
> }
>
> //make the rest regular
> using (Font font = new Font("Arial", 12f))
> {
> SizeF sz = e.Graphics.MeasureString("|", Font);
> float h = sz.Height + leading;
>
> for (int i2 = 6; i2 < listBox9.Items.Count; i2++)
> e.Graphics.DrawString(listBox9.Items[i2].ToString(), font,
> Brushes.Black, leftMargin, topMargin + h * i2, fmt);
> }
> }
>
> listBox9.BeginUpdate();
>
> string MAT = "MAT:";
> string KNR = "KNR";
> string SPANNUNG = "SPANNUNG";
>
> //select the item, from where the deletion should start
> for (int i = 0; i < listBox9.Items.Count; i++)
> {
> if (listBox9.Items[i].ToString().Contains(KNR))
> {
> listBox9.SetSelected(i + 1, true);
> }
> else if (listBox9.Items[i].ToString().Contains(MAT))
> {
> listBox9.ClearSelected();
> listBox9.SetSelected(i + 1, true);
> }
> else if (listBox9.Items[i].ToString().Contains(SPANNUNG))
> {
> listBox9.ClearSelected();
> listBox9.SetSelected(i + 1, true);
> }
> }
>
> //select all items between "SPANNUNG" and "LBL1"
> for (int i2 = listBox9.SelectedIndex; i2 < listBox9.Items.Count; i2++)
> {
> listBox9.SetSelected(i2, true);
> if (listBox9.Items[i2 + 1].ToString().Contains("LBL1"))
> {
> break;
> }
> }
>
> // delete all selected items between "SPANNUNG" and "LBL1", that I don't need
> var selected = listBox9.SelectedItems.Cast<Object>().ToArray();
> var selectedIndices = new List<int>(listBox9.SelectedIndices.Cast<int>());
> selectedIndices.Reverse();
> selectedIndices.ForEach(index => listBox9.Items.RemoveAt(index));
>
> // insert to spaces between "SPANNUNG" and "LBL1"
> for (int i3 = 0; i3 < listBox9.Items.Count; i3++)
> {
> if (listBox9.Items[i3].ToString().Contains("LBL1"))
> {
> listBox9.SetSelected(i3, true);
> listBox9.Items.Insert(listBox9.SelectedIndex, "");
> listBox9.Items.Insert(listBox9.SelectedIndex, "");
> break;
> }
> }
>
> listBox9.ClearSelected();
> listBox9.EndUpdate();