Parse and format date in c#

when use '/' in pattern, must use '\' to escape it,
when get formatted date string, use the following method:

datefrom.ToString("yyyy-MM-dd")

   1: DateTime datefrom;

   2: try

   3: {

   4:     datefrom = DateTime.ParseExact(txtFromDate.Text.Trim(), "MM\\/dd, yyyy", null); 

   5: }

   6: catch (Exception)

   7: {

   8:     datefrom = new DateTime(1900, 1, 1); 

   9: }