public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            MyGroupBox mgb1 = new MyGroupBox();
            mgb1.Name = "GroupBox1";
            mgb1.BackColor = Color.LightBlue;
            mgb1.ForeColor = Color.LightBlue;
            mgb1.Text = "test";
            mgb1.Location = new System.Drawing.Point(53, 35);
            mgb1.Size = new System.Drawing.Size(200, 100);


        }

        public class MyGroupBox : GroupBox
        {
            private Color _borderColor = Color.Black;

            public Color BorderColor
            {
                get { return this._borderColor; }
                set { this._borderColor = value; }
            }

            protected override void OnPaint(PaintEventArgs e)
            {
                //get the text size in groupbox
                Size tSize = TextRenderer.MeasureText(this.Text, this.Font);

                Rectangle borderRect = e.ClipRectangle;
                borderRect.Y = (borderRect.Y + (tSize.Height / 2));
                borderRect.Height = (borderRect.Height - (tSize.Height / 2));
                ControlPaint.DrawBorder(e.Graphics, borderRect, this._borderColor, ButtonBorderStyle.Solid);

                Rectangle textRect = e.ClipRectangle;
                textRect.X = (textRect.X + 6);
                textRect.Width = tSize.Width;
                textRect.Height = tSize.Height;
                e.Graphics.FillRectangle(new SolidBrush(this.BackColor), textRect);
                e.Graphics.DrawString(this.Text, this.Font, new SolidBrush(this.ForeColor), textRect);
            }
        }
    }