Validate Date

Question

I have a text box on a web form where a user will input a Discharge Date...The date MUST be entered in this format MM/DD/YYYY what C# code would validate that the entry is input in that format, and if not show an error? Something like:
ButtonFinish_Click()
{
//check to see if the date is correct format
try
{
//how to check?
//if valid Response.Redirect -- Go to next page
}
catch
{
Error.Text = "Dates must be entered in a MM/DD/YYYY Format. Please check the entry and try again."

Vulpes · Answer

I's use something like this: DateTime dt; if (DateTime.TryParseExact(textBox1.Text MM/dd/yyyy null 0 out dt)) { // it's OK and result is in 'dt' } else { // it's not OK }

Vulpes · Answer

When you pass 'null' for that particular parameter then the current culture is used (en-US in Richard's case). So with a simple date format such as MM/dd/yyyy it doesn't matter whether you use that or the Invariant culture.

Suthish Nair · Answer

A small change... But why just use a date control. DateTime dt1; if (DateTime.TryParseExact(date MM/dd/yyyy CultureInfo.InvariantCulture DateTimeStyles.None out dt1)) { Console.WriteLine(it's OK and result is in 'dt'); } else { Console.WriteLine(it's not OK); }

Vulpes · Answer

Are you sure that you've copied it down correctly as it's working OK for me? Note in particular that 'dt' should be preceded by 'out' as it's an output parameter. You can replace '0' with DateTimeStyles.None if you want to be more verbose.

richard smith · Answer

Lost me on that post. Where does that coding go? I don't think it is C# coding... I am assuming that is javascript and I need it to be C#

Satyapriya Nayak · Answer

Untitled Page function dateValidation() { var obj = document.getElementById( ); var day = obj.value.split(/)[0]; var month = obj.value.split(/)[1]; var year = obj.value.split(/)[2]; if ((day 31) || (month 12)&&(year.length != 4)) { alert(Invalid Format);return false; } } http://paulschreiber.com/blog/2007/03/02/javascript-date-validation/

richard smith · Answer

When I add that syntax I get an error of: The best overloaded method match for System.DateTime.TryParseExact(string string SystemIFormatProvider System.Globalization.DateTimeStyles out System.DateTime) has some invalid arguments.