C#

void OpenImageViewer(string f) {
    Process proc=new Process();
    proc.StartInfo.FileName=@"C:\WINDOWS\system32\rundll32.exe";
    proc.StartInfo.Arguments=@"C:\WINDOWS\system32\shimgvw.dll,ImageView_Fullscreen "+f;
    proc.StartInfo.UseShellExecute=true;
    proc.Start();
}

void OpenDefaultTool(string f) {
    Process proc=new Process();
    proc.StartInfo.FileName=f;
    proc.StartInfo.Arguments=null;
    proc.StartInfo.UseShellExecute=true;
    proc.Start();
}

Libor Tinka wrote:

Is is possible to use databases as well (in app release, that does not contain huge server tools)

Libor Tinka wrote:

he may not use Windows (my app should work on other platforms)

Graphics g;
g = e.Graphics;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(System.Drawing.Imaging.Metafile.FromFile("logo.wmf"), new Rectangle(0,0,200,200));

protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)

private void frmWelcome_Paint(object sender, PaintEventArgs e)

private void btnStart_Click(object sender, System.EventArgs e) {
    log("button Start got clicked");
    doSomething();
}

private void log(string s) {
    Console.WriteLine(s);
}

private void doSomething() {
    log("doing something");
}