Convert.ToDateTime throws exception when language is set to Arabic(SaudiArebia)

Question

Hi,

I am changing UI language based on user selection as below

Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.GetCultureInfo(ChangeLanguageTo);
Thread.CurrentThread.CurrentUICulture = System.Globalization.CultureInfo.GetCultureInfo(ChangeLanguageTo);

When language is changed To Arabic following line of code thows exception "String was not recognized as a valid DateTime".

newDataTableRow["Start"] = pEventItem.Start.DateTime.HasValue ? Convert.ToDateTime(pEventItem.Start.DateTime) : Convert.ToDateTime(pEventItem.Start.Date);

Here PEventItem is of type Google.Apis.Calendar.v3.Data.Event; Here I am trying to read existing Google calendar event item.

I tried to set 2nd parameter of the Convert.ToDateTime function in an hope that it might convert date correctly... eg.

CultureInfo enUsCulture = new CultureInfo("en-us");
newDataTableRow["Start"] = pEventItem.Start.DateTime.HasValue ? Convert.ToDateTime(pEventItem.Start.DateTime, enUsCulture) : Convert.ToDateTime(pEventItem.Start.Date, enUsCulture);

Well Now it does not throw exception, but the returned date is incorrect. value retuned is {21/10/40 12:00:00 ص}

while The actual date pEventItem.Start.Date is "2019-06-24" (as seen from debug window)

What could be the issue ? Can anyone guide please .

Regards

Answer 1

Hi @DaisyTian-MSFT

Here i was experimenting with a code.

private void btn1_Click(object sender, RoutedEventArgs e)
    {
        string strDate = "2021-01-01T14:30:00+05:30";
        StringBuilder strList = new StringBuilder();

        strList.Append(string.Format("Original String Date : {0}{1}", strDate, Environment.NewLine));

        DateTime d1 = Convert.ToDateTime(strDate);
        strList.Append(string.Format("Thread Culture: {0} -> DateTime d1 = Convert.ToDateTime(strDate);  returns : {1}{2}", Thread.CurrentThread.CurrentCulture.Name,  d1.ToString(), Environment.NewLine));

        DateTime d2 = Convert.ToDateTime(strDate,  CultureInfo.GetCultureInfo("ar-SA"));
        strList.Append(string.Format("Thread Culture: {0} ->      DateTime d2 = Convert.ToDateTime(strDate,  CultureInfo.GetCultureInfo('ar-SA'));  returns : {1}{2}", Thread.CurrentThread.CurrentCulture.Name, d2.ToString(), Environment.NewLine));

        DateTime d3 = Convert.ToDateTime(strDate, CultureInfo.GetCultureInfo("ja-JP"));
        strList.Append(string.Format("Thread Culture: {0} ->      DateTime d3 = Convert.ToDateTime(strDate,  CultureInfo.GetCultureInfo('ja-JP'));  returns : {1}{2}", Thread.CurrentThread.CurrentCulture.Name, d3.ToString(), Environment.NewLine));

        var ss = d1.ToString(CultureInfo.GetCultureInfo("ar-SA"));
        strList.Append(string.Format("Thread Culture: {0} ->     var ss = d1.ToString(CultureInfo.GetCultureInfo('ar-SA'));     returns : {1}{2}", Thread.CurrentThread.CurrentCulture.Name, ss, Environment.NewLine));

        DateTime d4 = Convert.ToDateTime(d1, CultureInfo.GetCultureInfo("ar-SA"));
        strList.Append(string.Format("Thread Culture: {0} ->     DateTime d4 = Convert.ToDateTime(d1, CultureInfo.GetCultureInfo('ar-SA'));     returns : {1}{2}", Thread.CurrentThread.CurrentCulture.Name, d4.ToString(), Environment.NewLine));


        var culture = new CultureInfo("ar-SA") { NumberFormat = { DigitSubstitution = DigitShapes.NativeNational } };
        Thread.CurrentThread.CurrentCulture = culture;
        Thread.CurrentThread.CurrentUICulture = culture;
        strList.Append(string.Format("Thread Culture: {0} ->   DateTime.Now.ToString();      returns : {1}{2}", Thread.CurrentThread.CurrentCulture.Name, DateTime.Now.ToString(), Environment.NewLine));

        tbResult.Text = strList.ToString();
    }

and it produce the following output.

1. Original String Date : 2021-01-01T14:30:00+05:30
2. Thread Culture: en-US -> DateTime d1 = Convert.ToDateTime(strDate); returns : 1/1/2021 2:30:00 PM
3. Thread Culture: en-US -> DateTime d2 = Convert.ToDateTime(strDate, CultureInfo.GetCultureInfo('ar-SA')); returns : 1/1/2021 2:30:00 PM
4. Thread Culture: en-US -> DateTime d3 = Convert.ToDateTime(strDate, CultureInfo.GetCultureInfo('ja-JP')); returns : 1/1/2021 2:30:00 PM
5. Thread Culture: en-US -> var ss = d1.ToString(CultureInfo.GetCultureInfo('ar-SA')); returns : 17/05/42 02:30:00 م
6. Thread Culture: en-US -> DateTime d4 = Convert.ToDateTime(d1, CultureInfo.GetCultureInfo('ar-SA')); returns : 1/1/2021 2:30:00 PM
7. Thread Culture: ar-SA -> DateTime.Now.ToString(); returns : 06/07/42 04:18:44 م

At Point 2, 5 and 6 , I was expecting it would return 17/05/42 02:30:00 م but strangely it returns 1/1/2021 2:30:00 PM ignoring given culture ar-SA.

Why so ?

Regards