DateTime dtm = new DateTime(2014, 05, 15);
String val = dtm.ToString("dd-mm-yyyy");
String val = dtm.ToString("dd/mm/yyyy");
String val = dtm.ToString("dd*mm*yyyy");
String val = dtm.ToString("mm-dd-yyyy");
String val = dtm.ToString("dd-yyyy-mm");
String val = dtm.ToString("yyyy!dd!mm");
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