C#

protected override void OnPaint(PaintEventArgs e)
{
   base.OnPaint (e);

   e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;

   GraphicsPath path = new GraphicsPath();
   path.AddString("Sample text", base.Font.FontFamily, (int)base.Font.Style, 
      base.Font.Size * 3, new PointF(10, 10), new StringFormat());

   using (Pen pen = new Pen(Color.White, 3))
   {
      e.Graphics.DrawPath(pen, path);
   }

   using (SolidBrush brush = new SolidBrush(Color.Red))
   {
      e.Graphics.FillPath(brush, path);
   }
}

private bool CheckTextBoxes()
{
	foreach(Control control in this.Controls)
	{
		TextBox textBox = control as TextBox;
		if(textBox != null)
		{
			foreach(Control otherControl in this.Controls)
			{
				TextBox otherTextBox = otherControl as TextBox;
				if(otherTextBox != null)
				{
					if(!otherTextBox.Equals(textBox))
					{
						if(otherTextBox.Text == textBox.Text)
						{
							return false;
						}
					}
				}
			}
		}
	}

	return true;
}

private bool CheckTextBoxes(params TextBox[] textboxes)
{
    bool result = true;
    if (textboxes.Length > 0)
    {
        string standardText = textboxes[0].Text;
        for(int i = 1; i < textboxes.Length; i++)
        {
            if (textboxes[i].Text != standardText)
            {
                result = false;
                break;
            }
        }
    }
    return result;
}

bool equality = CheckTextBoxes(textbox1, textbox2, textbox3, textbox4, textbox5, textbox6);

WindowsPrincipal wp = new WindowsPrincipal(WindowsIdentity.GetCurrent());
Console.WriteLine(wp.Identity.Name);