TimeSpanValueConverter for DevExpress XPO - save TimeSpan to database in seconds

TimeSpanValueConverter.cs

public class TimeSpanValueConverter : ValueConverter
{
    public override Type StorageType { get { return typeof(Int32); } }
    public override object ConvertToStorageType(object value)
    {
        if (!(value is TimeSpan)) return null;
        return Convert.ToInt32(Math.Truncate(((TimeSpan)value).TotalSeconds));
    }
    public override object ConvertFromStorageType(object value)
    {               
        if (!(value is Int32)) return null;
        return TimeSpan.FromSeconds((Int32)value);
    }
}