Print Using Selecting Printer

Step1: Associate control to Print document

private void printDocument1_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
{
           e.Graphics.DrawString(richTextBox1.Text, richTextBox1.Font, Brushes.Black, 100, 20);
           e.Graphics.PageUnit = GraphicsUnit.Inch;        
}

Step2:  write code for printing and print preview.

private void btnPrint_Click(object sender, EventArgs e)
{
            //PrintDialog associate with PrintDocument;
            printDialog1.Document = printDocument1;

            if (printDialog1.ShowDialog()==DialogResult.OK)
            {
                printDocument1.Print();
            }
}

private void btnPrintPreview_Click(object sender, EventArgs e)
{
            //Associate PrintPreviewDialog with PrintDocument.
            printPreviewDialog1.Document = printDocument1;
 
            // Show PrintPreview Dialog
            printPreviewDialog1.ShowDialog();
}