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| using System;
using System.Windows.Forms;
namespace UIComponent
{
/// <summary>
/// Summary description for DateTimePicker.
/// </summary>
public class DateTimePicker : System.Windows.Forms.DateTimePicker
{
private DateTimePickerFormat oldFormat = DateTimePickerFormat.Long;
private string oldCustomFormat = null;
private bool bIsNull = false;
public DateTimePicker() : base()
{
}
public new DateTime Value
{
get
{
if (bIsNull)
return DateTime.MinValue;
else
return base.Value;
}
set
{
if (value == DateTime.MinValue)
{
if (bIsNull == false)
{
oldFormat = this.Format;
oldCustomFormat = this.CustomFormat;
bIsNull = true;
}
this.Format = DateTimePickerFormat.Custom;
this.CustomFormat = " ";
}
else
{
if (bIsNull)
{
this.Format = oldFormat;
this.CustomFormat = oldCustomFormat;
bIsNull = false;
}
base.Value = value;
}
}
}
protected override void OnCloseUp(EventArgs eventargs)
{
if (Control.MouseButtons == MouseButtons.None)
{
if (bIsNull)
{
this.Format = oldFormat;
this.CustomFormat = oldCustomFormat;
bIsNull = false;
}
}
base.OnCloseUp (eventargs);
}
protected override void OnKeyDown(KeyEventArgs e)
{
base.OnKeyDown (e);
if (e.KeyCode == Keys.Delete)
this.Value = DateTime.MinValue;
}
}
} |
