tiempo de suma de datetimepicker en cuadro de texto - c #

en c# en un formulario de Windows tengo cinco timepicker only time format. Los cuatro valores están escritos en 4 cuadros de texto. Necesito en un quinto textbox o timepicker, para ver la suma de horas de pprecedenti 4.

este código es incorrecto:

TimeSpan result = this.dateTimePicker22.Value + this.dateTimePicker23.Value + this.dateTimePicker24.Value + this.dateTimePicker25.Value + this.dateTimePicker26.Value);
this.textBox21.Text = result.ToString();

Calculo las horas de trabajo así que:

    private void Calcolaweek1()
{
textBox23.MaxLength = 5;
DeleteChars();
if (textBox23.Text.Length == 2)
textBox23.Text += ":";

textBox23.SelectionStart = textBox23.Text.Length;

DateTime time = new DateTime();
this.textBox23.Text = time.ToString("HH:mm");


if ((textBox1.Text.Length > 0) && (textBox2.Text.Length > 0) && (textBox3.Text.Length > 0) && (textBox4.Text.Length > 0))
{
textBox23.MaxLength = 5;
TimeSpan result = this.dateTimePicker4.Value - this.dateTimePicker1.Value - (this.dateTimePicker3.Value - this.dateTimePicker2.Value);
this.textBox23.Text = result.ToString();

}
else if ((string.IsNullOrEmpty(textBox2.Text)) || (string.IsNullOrEmpty(textBox3.Text)))
{

TimeSpan result1 = this.dateTimePicker4.Value - this.dateTimePicker1.Value;
this.textBox23.Text = result1.ToString();
}

}

Debo resumir todas las horas de trabajo del día

Respuestas

private void btnCalculate_Click(object sender, EventArgs e)
{
try
{
int hours = picker1.Value.Hour % 12 +
picker2.Value.Hour % 12 +
picker3.Value.Hour % 12 +
picker4.Value.Hour % 12 +
picker5.Value.Hour % 12;

int minutes = picker1.Value.Minute % 60 +
picker2.Value.Minute % 60 +
picker3.Value.Minute % 60 +
picker4.Value.Minute % 60 +
picker5.Value.Minute % 60;

TimeSpan fromMinutes = TimeSpan.FromMinutes(minutes);
var ts = hours + fromMinutes.Hours + ":" + fromMinutes.Minutes;
}
catch (Exception)
{
throw;
}
}