解析时，字符串未被识别为有效的DateTime

Question

I get the following exception when converting to DateTime:

String was not recognized as a valid DateTime.

---

lbl_RequestDate.Text = "13/2/2013";

CultureInfo provider = CultureInfo.CurrentCulture;
string[] format = provider.DateTimeFormat.GetAllDateTimePatterns();
Follow.RequestDate = DateTime.ParseExact(lbl_RequestDate.Text, format, provider, DateTimeStyles.None);

Answer 1

You can use thje format d/M/yyyy , Notice the single M used for the month.

Follow.RequestDate = DateTime.ParseExact(lbl_RequestDate.Text, "d/M/yyyy", provider, DateTimeStyles.None);

The method: provider.DateTimeFormat.GetAllDateTimePatterns() returns almost 155 formats, but none of them (from your current culture seems to) supports format d/M/yyyy that is why you are getting the exception. If your date has Month as 13/02/2013 then the formats returned by the method would work since the closest format is dd/MM/yyyy in the formats array.

Answer 2

Maybe this will help :

DateTime.ParseExact("13/2/2013","d/M/yyyy",CultureInfo.GetCultureInfo("en-US"), DateTimeStyles.None );

notice :

d is for Day  (01 is also acceptable)
M is for Month (11 is also acceptable) 

Answer 3

试试这样：

Follow.RequestDate = DateTime.ParseExact(lbl_RequestDate.Text, "d/M/yyyy", CultureInfo.InvariantCulture);

Answer 4

DateTimeFormatInfo.GetAllDateTimePatterns() method returns on my machine ( tr-TR Culture) 29 format but none of these support d/M/yyyy date format, that's why you are getting FormatException .

But in my culture DateSeparator is . so I can't exactly solve this problem using CultureInfo.CurrentCulture but when I use Egypt cultureinfo (it's wrote on your profile) CultureInfo.GetCultureInfo("ar-EG") this code works without any error;

CultureInfo provider = CultureInfo.GetCultureInfo("ar-EG");
string[] format = provider.DateTimeFormat.GetAllDateTimePatterns();
DateTime d = DateTime.ParseExact("13/02/2013", format, provider, DateTimeStyles.None);

Unfortunatly your your all datetime pattern doesn't support d/M/yyyy format.

Unfortunatly , changing this string to 13/02/2013 doesn't solve this problem because as I said on before, my all formats (in tr-TR Culture) doesn't support dd/MM/yyyy format either.

My humble advice is here, list all your datetime patterns and check manually if your string is recognized format with this datetime pattern like;

string[] format = provider.DateTimeFormat.GetAllDateTimePatterns();
foreach (var f in format)
{
    ///
}