Best practice in checking if a string is a datetime before converting?

Question

What's the best way to do it?

This is how I'll usually do it:

DateTime newDate;

try
{
    newDate = DateTime.Parse(Textbox.Text);
}
catch
{
    //isn't a datetime
    return;
}

//do stuff with the date

But something tells me that that is a bit wrong. Any ideas?

Answer 1

Use the DateTime.TryParse method instead of using your own try/catch blocks.

string text = "10/16/2009";
DateTime result;

if (DateTime.TryParse(text, out result))
{
    // success, result holds converted value
}
else
{
    // failed
}

Answer 2

The best pattern to use for datetime parsing would be this

string DateFormat = "dd/MM/yyyy"; //Or any other format
DateTime dateTime;
bool success = DateTime.TryParseExact(value, DateFormat, 
       CultureInfo.InvariantCulture, 
           DateTimeStyles.None, 
                out dateTime);

Never use DateTime.Parse and even DateTime.TryParse

Answer 3

If you know what the format of the datetime will be, you can also use DateTime..::.TryParseExact Method

The DateTime.TryParse can cause problems when it is used with dates such as 01/03/2009

Is it 01 Mar or 03 Jan?

I would rather recomend that you use something other than a textbox, like a date picker, or validate the textbox so that you have something like dd MMM yyyy. very seldomly would you go wrong with that.