将转换后的String排序为DateTime列。

Question

My DataTable has a Date column which must accept several different DateTime formats. I'd like to consolidate these under one form and then sort accordingly by date.

So far I've written the code below to change the way the date is displayed. But it still doesn't sort properly. What's displayed isn't what's used when sorting. It still uses the old format.

So 2018-05-30 still goes after 2018-09-05 because the system is reading the data before it was converted as 30/05/2018 and 05/09/2018. and because 30 > 05 it sorts improperly. Anyone have any suggestions?

        if (e.PropertyName.Contains("Date"))
        {
            DataGridTextColumn dgtc = e.Column as DataGridTextColumn;
            DateTimeConverter con = new DateTimeConverter();
            (dgtc.Binding as Binding).Converter = con;
        }


    public class DateTimeConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value != null)
            {
                try
                {
                    return DateTime.Parse(value.ToString()).ToString("yyyy-MM-dd");
                }
                catch
                {
                    return value;
                }
            }
            return value;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value != null && value.GetType() == typeof(System.DateTime))
            {
                DateTime t = (DateTime)value;
                return t.ToShortDateString();
            }
            return value;
        }


    }

Answer 1

have you tried

List<DateTime> yourdateTime = new List<DateTime>();
yourdateTime.OrderBy(x => x.Date);

also look at

yourdateTime.OrderBy(x => x.Date.TimeOfDay)
.ThenBy(x => x.Date.Date)
.ThenBy(x => x.Date.Year);

once you are into the Date Class you have lots of ways to sort it. just make sure if you use more than one to use OrderBy first and ThenBy for subsequent passes.

Answer 2

Set the SortMemberPath property of the DataGridColumn to "Date" if this is what your date column/property is called. Then it should sort the column by this property regardless of the formatting.

But you don't need to use a converter to format the date. You could just set the StringFormat property of the binding:

if (e.PropertyName.Contains("Date"))
{
    DataGridTextColumn dgtc = e.Column as DataGridTextColumn;
    dgtc.Binding = new Binding(e.PropertyName) { StringFormat = "yyyy-MM-dd" };
}