DateTime.TryParse解析为错误的格式

Question

I am trying to parse a string (from a Textbox filled with english dateformat) to a DateTime using this code:

DateTime dt;
if (DateTime.TryParseExact(Text, DateTimeFormat, System.Threading.Thread.CurrentThread.CurrentCulture, DateTimeStyles.AssumeLocal, out dt))
{
    logger.Trace("LOCALE: {0} ", System.Threading.Thread.CurrentThread.CurrentCulture);
    logger.Trace("DateTimeFormat: {0} ", DateTimeFormat);
    logger.Trace("CurrentCulture ShortDatePattern: {0} ", System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.ShortDatePattern);
    logger.Trace("Text: {0} ", Text);
    logger.Trace("result of TryParse: {0} ", dt);
    return dt;
}

However the output in my logger is:

LOCALE: en-US 
DateTimeFormat ShortDatePattern: M/d/yyyy 
CurrentCulture ShortDatePattern: M/d/yyyy 
Text: 8/31/2012 
result of TryParse: 31-8-2012 0:00:00 

I am completly stuck why this is happening.

Using this code in a seperate console application DOES work:

Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US");
string text = @"8/31/2012";
DateTime date;
string dateTimeFormat = @"M/d/yyyy";
bool parseOk = DateTime.TryParseExact(text, dateTimeFormat, Thread.CurrentThread.CurrentCulture, DateTimeStyles.AssumeLocal, out date);

extra info:

• system: Windows 7 Ultimate EN
• system language for non-UniCode: english
• web.config system.web:

PROBLEM: The problem is I want the date to be in the format "M/d/yyyy" but instead it is parsed to "dd-mm-yyyy" which results in an invalid date

Answer 1

You have not specified an output string for the log entry, so it will use the default one (based on the current culture).

So, instead of:

logger.Trace("result of TryParse: {0} ", dt);

Use:

logger.Trace("result of TryParse: {0} ", dt.ToString("M/dd/yyyy"));

Or:

logger.Trace("result of TryParse: {0} ", dt.ToShortDateString());