你好:
检查可以:

Hello :
to check you can :

if (DateTime.TryParseExact(TextBox1.Text, "MM/dd/yyyy", null, DateTimeStyles.None, out Test) == true)

否则，您无需检查即可直接将字符串更改为所需的任何格式:

else instead of checking you can directly change the string to any format you want :

DateTime dt = new DateTime(2008, 3, 9, 16, 5, 7, 123);

String.Format("{0:y yy yyy yyyy}", dt);  // "8 08 008 2008"   year
String.Format("{0:M MM MMM MMMM}", dt);  // "3 03 Mar March"  month
String.Format("{0:d dd ddd dddd}", dt);  // "9 09 Sun Sunday" day
String.Format("{0:h hh H HH}",     dt);  // "4 04 16 16"      hour 12/24
String.Format("{0:m mm}",          dt);  // "5 05"            minute
String.Format("{0:s ss}",          dt);  // "7 07"            second
String.Format("{0:f ff fff ffff}", dt);  // "1 12 123 1230"   sec.fraction
String.Format("{0:F FF FFF FFFF}", dt);  // "1 12 123 123"    without zeroes
String.Format("{0:t tt}",          dt);  // "P PM"            A.M. or P.M.
String.Format("{0:z zz zzz}",      dt);  // "-6 -06 -06:00"   time zone

问候...

regards...

尝试:

DateTime result;
if (DateTime.TryParseExact(myTextBox.Text, "dd/MMM/yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None, out result))
{
    // OK
}
else
{
    // Error!
}