DataGridView и календарь - C#

public class CalendarColumn : DataGridViewColumn
{
    public CalendarColumn() : base(new CalendarCell()) { }
 
    public override DataGridViewCell CellTemplate
    {
        get
        {
            return base.CellTemplate;
        }
        set
        {
            // Ensure that the cell used for the template is a CalendarCell
            if (value != null && !value.GetType().IsAssignableFrom(typeof(CalendarCell)))
            {
                throw new InvalidCastException("Must be a CalendarCell");
            }
            base.CellTemplate = value;
        }
    }
}
 
public class CalendarCell : DataGridViewTextBoxCell
{
    public CalendarCell() : base()
    {
        // Use the short date format.
        this.Style.Format = "d";
    }
 
    public override void InitializeEditingControl(int rowIndex, objectinitialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
    {
        // Set the value of the editing control to the current cell value
        base.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle);
        CalendarEditingControl ctl = DataGridView.EditingControl asCalendarEditingControl;
 
        // Set row value when Value property is not null
        if (this.Value != null)
        {
            ctl.Value = (DateTime)this.Value;
        }
    }
 
    public override Type EditType
    {
        get
        {
            // Return the type of the editing control that CalendarCell uses
            return typeof(CalendarEditingControl);
        }
    }
 
    public override Type ValueType
    {
        get
        {
            // Return the type of the value that CalendarCell contains
            return typeof(DateTime);
        }
    }
}
 
public class CalendarEditingControl : DateTimePicker,IDataGridViewEditingControl
{
    private DataGridView _dataGridView;
    private bool _valueChanged;
    private int _rowIndex;
 
    public CalendarEditingControl()
    {
        this.Format = DateTimePickerFormat.Short;
    }
 
    // Implements the IDataGridViewEditingControl.EditingControlFormattedValue property
    public object EditingControlFormattedValue
    {
        get
        {
            return this.Value.ToShortDateString();
        }
        set
        {
            if (value is String)
            {
                try
                {
                    // This will throw an exception of the string is null, empty, or not in the format of a date
                    this.Value = DateTime.Parse((String)value);
                }
                catch
                {
                    // In the case of an exception, just use the default value so we're not left with a null value
                    this.Value = DateTime.Now;
                }
            }
        }
    }
 
    // Implements the IDataGridViewEditingControl.GetEditingControlFormattedValue method
    public object GetEditingControlFormattedValue(DataGridViewDataErrorContextscontext)
    {
        return EditingControlFormattedValue;
    }
 
    // Implements the IDataGridViewEditingControl.ApplyCellStyleToEditingControl method
    public void ApplyCellStyleToEditingControl(DataGridViewCellStyledataGridViewCellStyle)
    {
        this.Font = dataGridViewCellStyle.Font;
        this.CalendarForeColor = dataGridViewCellStyle.ForeColor;
        this.CalendarMonthBackground = dataGridViewCellStyle.BackColor;
    }
 
    // Implements the IDataGridViewEditingControl.EditingControlRowIndex property
    public int EditingControlRowIndex
    {
        get
        {
            return _rowIndex;
        }
        set
        {
            _rowIndex = value;
        }
    }
 
    // Implements the IDataGridViewEditingControl.EditingControlWantsInputKey method
    public bool EditingControlWantsInputKey(Keys key, booldataGridViewWantsInputKey)
    {
        // Let the DateTimePicker handle the keys listed
        switch (key & Keys.KeyCode)
        {
            case Keys.Left:
            case Keys.Up:
            case Keys.Down:
            case Keys.Right:
            case Keys.Home:
            case Keys.End:
            case Keys.PageDown:
            case Keys.PageUp:
                return true;
            default:
                return !dataGridViewWantsInputKey;
        }
    }
 
    // Implements the IDataGridViewEditingControl.PrepareEditingControlForEdit method
    public void PrepareEditingControlForEdit(bool selectAll) { }
 
    // Implements the IDataGridViewEditingControl.RepositionEditingControlOnValueChange property
    public bool RepositionEditingControlOnValueChange
    {
        get
        {
            return false;
        }
    }
 
    // Implements the IDataGridViewEditingControl.EditingControlDataGridView property
    public DataGridView EditingControlDataGridView
    {
        get
        {
            return _dataGridView;
        }
        set
        {
            _dataGridView = value;
        }
    }
 
    // Implements the IDataGridViewEditingControl.EditingControlValueChanged property
    public bool EditingControlValueChanged
    {
        get
        {
            return _valueChanged;
        }
        set
        {
            _valueChanged = value;
        }
    }
 
    // Implements the IDataGridViewEditingControl.EditingPanelCursor property
    public Cursor EditingPanelCursor
    {
        get
        {
            return base.Cursor;
        }
    }
 
    protected override void OnValueChanged(EventArgs eventargs)
    {
        // Notify the DataGridView that the contents of the cell have changed
        _valueChanged = true;
        this.EditingControlDataGridView.NotifyCurrentCellDirty(true);
        base.OnValueChanged(eventargs);
    }
}