System.ComponentModel.DateTimeConverter.ConvertTo C# (CSharp) Method

        public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
        {
            if (destinationType == typeof(string) && value is DateTime)
            {
                DateTime dt = (DateTime)value;
                if (dt == DateTime.MinValue)
                {
                    return string.Empty;
                }

                if (culture == null)
                {
                    culture = CultureInfo.CurrentCulture;
                }

                DateTimeFormatInfo formatInfo = null;
                formatInfo = (DateTimeFormatInfo)culture.GetFormat(typeof(DateTimeFormatInfo));

                string format;
                if (culture == CultureInfo.InvariantCulture)
                {
                    if (dt.TimeOfDay.TotalSeconds == 0)
                    {
                        return dt.ToString("yyyy-MM-dd", culture);
                    }
                    else
                    {
                        return dt.ToString(culture);
                    }
                }
                if (dt.TimeOfDay.TotalSeconds == 0)
                {
                    format = formatInfo.ShortDatePattern;
                }
                else
                {
                    format = formatInfo.ShortDatePattern + " " + formatInfo.ShortTimePattern;
                }

                return dt.ToString(format, CultureInfo.CurrentCulture);
            }

            return base.ConvertTo(context, culture, value, destinationType);
        }
    }

		public void IFormattable_DateTime ()
		{
			CultureInfo originalCulture = CultureInfo.CurrentCulture;

			try {
				Thread.CurrentThread.CurrentCulture = new CultureInfo ("nl-BE");
				DateTime today = DateTime.Today;
				DateTime now = DateTime.Now;

				table = new DataTable ();
				view = table.DefaultView;
				table.Columns.Add (new DataColumn ("Date", typeof (DateTime)));

				DataRow row = table.NewRow ();
				row ["Date"] = today;
				table.Rows.Add (row);

				row = table.NewRow ();
				row ["Date"] = now;
				table.Rows.Add (row);

				tableStyle = new DataGridTableStyle ();
				ColumnPoker dateColumnStyle = new ColumnPoker ();
				dateColumnStyle.MappingName = "Date";
				tableStyle.GridColumnStyles.Add (dateColumnStyle);

				BindingContext bc = new BindingContext ();
				DataGrid dg = new DataGrid ();
				dg.BindingContext = bc;
				dg.TableStyles.Add (tableStyle);
				dg.DataSource = table;

				CurrencyManager cm = (CurrencyManager) bc [view];
				TextBox tb = dateColumnStyle.TextBox;
				DateTimeConverter converter = new DateTimeConverter ();

				Assert.IsNotNull (tb, "#A1");
				Assert.AreEqual (string.Empty, tb.Text, "#A2");

				dateColumnStyle.DoEdit (cm, 0, new Rectangle (new Point (0,0), new Size (100, 100)), false, null, true);
				Assert.AreEqual (converter.ConvertTo (null, CultureInfo.CurrentCulture,
					today, typeof (string)), tb.Text, "#B1");
				Assert.AreEqual (today, table.Rows [0] ["Date"], "#B2");

				dateColumnStyle.DoEdit (cm, 1, new Rectangle (new Point (0,0), new Size (100, 100)), false, null, true);
				Assert.AreEqual (converter.ConvertTo (null, CultureInfo.CurrentCulture,
					now, typeof (string)), tb.Text, "#C1");
				Assert.AreEqual (now, table.Rows [1] ["Date"], "#C2");

				dateColumnStyle.Format = "MM";

				dateColumnStyle.DoEdit (cm, 0, new Rectangle (new Point (0,0), new Size (100, 100)), false, null, true);
				Assert.AreEqual (today.ToString ("MM", CultureInfo.CurrentCulture), tb.Text, "#D1");
				Assert.AreEqual (today, table.Rows [0] ["Date"], "#D2");

				dateColumnStyle.DoEdit (cm, 1, new Rectangle (new Point (0,0), new Size (100, 100)), false, null, true);
				Assert.AreEqual (now.ToString ("MM", CultureInfo.CurrentCulture), tb.Text, "#E1");
				Assert.AreEqual (now, table.Rows [1] ["Date"], "#E2");

				dateColumnStyle.DoEdit (cm, 0, new Rectangle (new Point (0,0), new Size (100, 100)), false, "INVALID", true);
				Assert.IsFalse (dateColumnStyle.DoCommit (cm, 0), "#F1");
				Assert.AreEqual ("INVALID", tb.Text, "#F2");
				Assert.AreEqual (today, table.Rows [0] ["Date"], "#F3");

				dateColumnStyle.DoEdit (cm, 0, new Rectangle (new Point (0,0), new Size (100, 100)), false, "12", true);
				Assert.IsFalse (dateColumnStyle.DoCommit (cm, 0), "#G1");
				Assert.AreEqual ("12", tb.Text, "#G2");
				Assert.AreEqual (today, table.Rows [0] ["Date"], "#G3");

				dateColumnStyle.DoEdit (cm, 0, new Rectangle (new Point (0,0), new Size (100, 100)), false, "07/09/2007", true);
				Assert.IsTrue (dateColumnStyle.DoCommit (cm, 0), "#H1");
				Assert.AreEqual (converter.ConvertTo (null, CultureInfo.CurrentCulture,
					new DateTime (2007, 9, 7), typeof (string)), tb.Text, "#H2");
				Assert.AreEqual (new DateTime (2007, 9, 7), table.Rows [0] ["Date"], "#H3");

				dateColumnStyle.FormatInfo = CultureInfo.CurrentCulture;

				dateColumnStyle.DoEdit (cm, 0, new Rectangle (new Point (0,0), new Size (100, 100)), false, "08/06/2005", true);
				Assert.IsTrue (dateColumnStyle.DoCommit (cm, 0), "#I1");
				Assert.AreEqual ("06", tb.Text, "#I2");
				Assert.AreEqual (new DateTime (2005, 6, 8), table.Rows [0] ["Date"], "#I3");
			} finally {
				Thread.CurrentThread.CurrentCulture = originalCulture;
			}
		}