Forms.Label label1;
Forms.Label label2;

Timer casovac = new Timer();
 
public Form1() {
    InitializeComponent();
}
 
private void Form1_Load(object sender, EventArgs e) {
    casovac.Interval = 1000;  //v milisekundách
    casovac.Tick += new EventHandler(this.dejCas);
    casovac.Start();
}
 
private void dejCas(object sender, EventArgs e) {
    int hodina = DateTime.Now.Hour;
    int minuta = DateTime.Now.Minute;
    int sekunda = DateTime.Now.Second;
 
    string cas = "";
 
    if (hodina < 10) {
        cas += "0" + hodina;
    } else {
        cas += hodina;
    }
    cas += ":";
 
    if (minuta < 10) {
        cas += "0" + minuta;
    } else {
        cas += minuta;
    }
    cas += ":";
 
    if (sekunda < 10) {
        cas += "0" + sekunda;
    } else {
        cas += sekunda;
    }
 
    label1.Text = cas;
 
//label1.Text = DateTime.Now.ToString("HH:mm:ss");
//label2.Text = DateTime.Now.Date.ToString("d. M. yyyy");
}