Accessing variables in other Windows Form class C#

Question

I want to push my var selectedDate from frmMain so it can use in frmEvent .

The var will make a label in frmEvent that var value. Here is my code:

private void monthCalendar1_SelectedDate(object sender, DateRangeEventArgs e)
    {
        var selectedDate = (DateTime.Parse(e.Start.ToShortDateString())).Day;
        frmEvent frmE = new frmEvent();
        frmE.Show();
    }

Answer 1

You can do one of two things. Either add a date to the constructor of frmEvent , or add a property to frmEvent and set it before calling .Show() .

Constructor way:

public partial class frmEvent : Form
{
  private int SelectedDate;
  public frmEvent(int selectedDate)
  {
    InitializeComponent();
    SelectedDate = selectedDate;
  }
}

public partial class frmMain : Form
{
    private void monthCalendar1_SelectedDate(object sender, DateRangeEventArgs e)
    {
        var selectedDate = (DateTime.Parse(e.Start.ToShortDateString())).Day;
        frmEvent frmE = new frmEvent(selectedDate);
        frmE.Show();
    }
}

Property way:

public partial class frmEvent : Form
{
    public int SelectedDate { get; set; }
    public frmEvent()
    {
        InitializeComponent();
    }
}

public partial class frmMain : Form
{
    private void monthCalendar1_SelectedDate(object sender, DateRangeEventArgs e)
    {
        var selectedDate = (DateTime.Parse(e.Start.ToShortDateString())).Day;
        frmEvent frmE = new frmEvent();
        frmE.SelectedDate = selectedDate;
        frmE.Show();
    }
}

Just treat the forms like normal classes, mostly because that is what they are and can be treated as such, do not overthink it.