c# - FieldConverter ConverterKind.Date "dd/MM/yyyy" exception -

i try read csv file. fifth record contans date: 03/11/2008

this piece of code:

    [fieldconverter(converterkind.date, "dd/mm/yyyy")]     public datetime datum_5; 

my code crashs on this:

result[] results= (result[])engine.readfile(@"..\data\expo.txt"); 

and exception: line: 1. column: 41. field: datum_5. error converting '03/11/2008' type: 'datetime'. using format: 'dd/mm/yyyy'

when this:

[fieldconverter(typeof(convertdate))]          public datetime datum_5; 

with this:

internal class convertdate : converterbase    {         /// <summary>        /// different forms date separator : . or / or space        /// </summary>        /// <param name="from">the string format of date - first day</param>        /// <returns></returns>         public override object stringtofield(string from)        {            datetime dt;             if (datetime.tryparseexact(from, "dd.mm.yyyy", null, datetimestyles.none, out dt))                return dt;             if (datetime.tryparseexact(from, "dd/mm/yyyy", null, datetimestyles.none, out dt))                return dt;             if (datetime.tryparseexact(from, "dd mm yyyy", null, datetimestyles.none, out dt))                return dt;             throw new argumentexception("can not make date " + from, "from");         }    } 

i got exception: can not make date 03/11/2008 parameternaam: from

what doing wrong?

the reason it's failing / in custom date format string a culture-specific dateseparator described in msdn.

you specifying null iformatprovider argument, it's using current culture, presumably has date separator other /.

the best solution explicitly specify cultureinfo.invariantculture (second version below). escaping '/' in custom date format string treated literal slash rather dateseparator work (first version below).

// set current culture culture uses "." dateseparator thread.currentthread.currentculture = new cultureinfo("de-de"); // work - escaping means uses literal / separator datetime.tryparseexact(s, @"dd\/mm\/yyyy", null, datetimestyles.none, out result);  // better - culture.invariantculture uses / datetimeformatinfo.dateseparator // , express intent use invariant culture datetime.tryparseexact(s, "dd/mm/yyyy", cultureinfo.invariantculture, datetimestyles.none, out result);  // fail - / means use datetimeformatinfo.dateseparator "." in de-de culture datetime.tryparseexact(s, "dd/mm/yyyy", null, datetimestyles.none, out result);