更改机器时间格式时，无法将字符串识别为有效的DateTime。

Question

I have a Date string in format dd/MM/yyyy I am string to get this string in 'yyyyMMdd' So I tried :

todate1 = Convert.ToDateTime(txttdate.Text).ToString("yyyyMMdd")

and it worked fine when my local machine time was in format dd/MM/yyyy but then when I change the system time format it stops working it gives me error

String was not recognized as a valid DateTime 

How do solve this problem? I need to convert dd/MM/yyyy string to yyyyMMdd

Answer 1

Use DateTime.ParseExact instead of Convert.ToDateTime and specify the pattern and InvariantCulture as format provider:

var todate1 = DateTime.ParseExact(@"05/12/2013", @"dd/MM/yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None).ToString("yyyyMMdd");

It should prevent your code from failure on different culture settings.

Answer 2

Use ParseExact and specifiy CultureInfo.InvariantCulture :

DateTime todate1;

if (DateTime.TryParseExact(txttdate.Text, new[] { "dd/MM/yyyy" }, CultureInfo.InvariantCulture, DateTimeStyles.None, out todate1)) {
    string yourNewFormat = todate1.ToString("yyyyMMdd");
}
else {
    // it failed
}

Using TryParseExact allows you to recover from potentially invalid dates being provided.

Answer 3

I had a similar problem in my web application, tried many things like above but nothing helped me. But when I added globalization tag in my config file it worked like a charm.

    <system.web>
      <globalization requestEncoding="UTF-8" responseEncoding="UTF-8" uiCulture="en-GB" culture="en-GB" />
    </system.web>

change culture to US or IN or whatever u want.