How to parse datetime from a specific timezone into UTC?

Question

I want to assume a specific timezone (EST) when reading datetime, and convert to UTC.

I tried this:

csvPropertyMap.TypeConverterOption(DateTimeStyles.AssumeLocal | DateTimeStyles.AdjustToUniversal);

But it won't work as my code is running in the cloud, where the local is UTC.

Is there a way to configure a TimeZoneInfo in the column mapping ?

Answer 1

This should work if you want to assume DateTime values are in a specific timezone and then convert them to UTC.

static void Main(string[] args)
{
    using (MemoryStream stream = new MemoryStream())
    using (StreamWriter writer = new StreamWriter(stream))
    using (StreamReader reader = new StreamReader(stream))
    using (CsvReader csv = new CsvReader(reader))
    {
        writer.WriteLine("Id,Name,FooDate");
        writer.WriteLine("1,Test,04/19/2019 05:42:00");
        writer.Flush();
        stream.Position = 0;

        var easternStandardTimeZone = TimeZoneInfo.FindSystemTimeZoneById("Eastern Standard Time");
        csv.Configuration.TypeConverterCache.RemoveConverter<DateTime>();
        csv.Configuration.TypeConverterCache.AddConverter<DateTime>(new TimeZonetoUtcConverter(easternStandardTimeZone));

        var records = csv.GetRecords<Foo>().ToList();

        Console.ReadKey();
    }

}

public class Foo
{
    public int Id { get; set; }
    public string Name { get; set; }
    public DateTime FooDate { get; set; }
}

public class TimeZonetoUtcConverter: DateTimeConverter
{
    private readonly TimeZoneInfo timeZoneInfo;

    public TimeZonetoUtcConverter(TimeZoneInfo timeZoneInfo)
    {
        this.timeZoneInfo = timeZoneInfo;
    }

    public override object ConvertFromString(string text, IReaderRow row, MemberMapData memberMapData)
    {
        var parsedDate = base.ConvertFromString(text, row, memberMapData);

        return TimeZoneInfo.ConvertTimeToUtc((DateTime)parsedDate, timeZoneInfo);
    }
}