Использование реестра

public Form1()
        {
            InitializeComponent();
            LoadProgrammProperties();
        }

private void LoadProgrammProperties()
        {
            RegistryKey registryKeyOptions = Registry.CurrentUser;
            registryKeyOptions = registryKeyOptions.CreateSubKey("Software");
            registryKeyOptions = registryKeyOptions.CreateSubKey("C#");
            registryKeyOptions = registryKeyOptions.CreateSubKey("TestFiles1");
 
            Width = (int)registryKeyOptions.GetValue("width", 600);
            Height = (int)registryKeyOptions.GetValue("heigth", 400);
            Left = (int)registryKeyOptions.GetValue("left", 50);
            Top = (int)registryKeyOptions.GetValue("top", 50);
 
            WindowState = (FormWindowState)registryKeyOptions.GetValue("WinState", FormWindowState.Normal);
            registryKeyOptions.Close();
        }

private void SaveProgrammProperties()
        {
            RegistryKey registryKeyOptions = Registry.CurrentUser;
            registryKeyOptions = registryKeyOptions.CreateSubKey("Software");
            registryKeyOptions = registryKeyOptions.CreateSubKey("C#");
            registryKeyOptions = registryKeyOptions.CreateSubKey("TestFiles1");
 
            registryKeyOptions.SetValue("WinState", (int)WindowState);
            if(WindowState == FormWindowState.Normal)
            {
                registryKeyOptions.SetValue("width", Width);
                registryKeyOptions.SetValue("height", Height);
                registryKeyOptions.SetValue("left", Left);
                registryKeyOptions.SetValue("top", Top);
            }
        }

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            SaveProgrammProperties();
        }