DateTimePicker in C# windows Form

Question

hi All,

i am using C# windows Application.

can possible to.? date field is disable. and only calendar field is enable.?
like image at below.

best regards
NazHim

Answer 1

The easy way is to place a TextBox and Button on the form, show a child form with a month calendar control. In the child form, select a date and click the Select button which sends the selected date to an event which the calling form places in a TextBox. If when calling the child form without a DateTime the current date is used, if there is a DateTime it's used.

Full source (calendar image is in the assets folder)

Form1

namespace WindowsFormsApp3  
{  
public partial class Form1 : Form  
{  
    public Form1()  
    {  
        InitializeComponent();  
          
        Shown += OnShown;  
    }  
  
    private void OnShown(object sender, EventArgs e)  
    {  
        ActiveControl = ShowCalendarButton;  
    }  
  
    private void ShowCalendarButton_Click(object sender, EventArgs e)  
    {  
        CalendarForm calendarForm = null;  
          
        try  
        {  
            // decide to pass a date time or not  
            calendarForm = DateTime.TryParse(DateTimeValueTextBox.Text, out var currentDateTime) ?   
                new CalendarForm(currentDateTime) :   
                new CalendarForm();  
  
            // reposition to be next to calendar button  
            calendarForm.Location = new Point(Left + (Width - 100), Bottom - 80);  
              
            calendarForm.DateTimeHandler += CalendarFormOnDateTimeHandler;  
            calendarForm.ShowDialog();  
  
        }  
        finally  
        {  
            calendarForm.DateTimeHandler -= CalendarFormOnDateTimeHandler;  
            calendarForm.Dispose();  
        }  
    }  
    // set date time  
    private void CalendarFormOnDateTimeHandler(DateTime sender)  
    {  
        DateTimeValueTextBox.Text = $"{sender.ToString("MM-dd-yyyy")}";  
    }  
}  

Calendar form

public partial class CalendarForm : Form  
{  
    public delegate void OnSelectDateTime(DateTime sender);  
    public event OnSelectDateTime DateTimeHandler;  
      
    public CalendarForm()  
    {  
        InitializeComponent();  
    }  
    public CalendarForm(DateTime sender)  
    {  
        InitializeComponent();  
        monthCalendar1.SetDate(sender);  
    }  
  
    private void SelectButton_Click(object sender, EventArgs e)  
    {  
        DateTimeHandler?.Invoke(monthCalendar1.SelectionRange.Start);  
        Close();  
    }  
}  

Cheap alternate

Create a KeyDown event for a DateTimePicker as follows

private void dateTimePicker1_KeyDown(object sender, KeyEventArgs e)  
{  
    e.Handled = true;  
}  

Answer 2

You can filter messages using the IMessageFilter Interface. If it is a key down or key up message then do not process it. For the calendar however the user might want to use the arrow keys so you can process the DropDown and CloseUp events and when the calendar is down, allow the keys to be processed. A complete sample is at Repos/Answers/DateDisabled at master · SimpleSamples/Repos.

public partial class Form1 : Form, IMessageFilter  
{  
    IntPtr dtphwnd = IntPtr.Zero;  
    bool CalendarDown = false;  

    public Form1()  
    {  
        InitializeComponent();  
        dtphwnd = dateTimePicker1.Handle;  
        Application.AddMessageFilter(this);  
    }  

    public bool PreFilterMessage(ref Message m)  
    {  
        const int WM_KEYDOWN = 0x0100;  
        const int WM_KEYUP = 0x0101;  
        if (CalendarDown)  
            return false;  
        // Does dateTimePicker1 exist?  
        if (dtphwnd == IntPtr.Zero)  
        {  
            return false;  
        }  
        // Is this message for the dateTimePicker1?  
        if (m.HWnd != dtphwnd)  
        {  
            return false;  
        }  
        // if key up or key down message then do not process it  
        if (m.Msg == WM_KEYDOWN || m.Msg == WM_KEYUP)  
            return true;    // stop it from being dispatched  
        // All other messages are processed  
        return false;  
    }  

    private void dateTimePicker1_CloseUp(object sender, EventArgs e)  
    {  
        CalendarDown = false;  
    }  

    private void dateTimePicker1_DropDown(object sender, EventArgs e)  
    {  
        CalendarDown = true;  
    }  

    private void Form1_FormClosed(object sender, FormClosedEventArgs e)  
    {  
        Application.RemoveMessageFilter(this);  
    }  
}