mservidio
commented
11 months ago For now, I'm working around this with the following:
public class CustomIsoDateTimeConverter : IsoDateTimeConverter
{
public override object? ReadJson(JsonReader reader, Type objectType, object? existingValue, JsonSerializer serializer)
{
string? value = reader.Value?.ToString();
if (reader.TokenType == JsonToken.String)
{
string? formattedString = null;
if (value != null && EnsureSevenNanos(value, out formattedString))
{
Console.WriteLine($"Date string was reformatted: {formattedString}");
DateTime date = DateTime.ParseExact(formattedString, "yyyy-MM-ddTHH:mm:ss.fffffffZ",
CultureInfo.InvariantCulture);
return date;
}
}
Console.WriteLine($"Using IsoDateTimeConverter default read behavior: {value}");
return base.ReadJson(reader, objectType, existingValue, serializer);
}
private static bool EnsureSevenNanos(string input, out string? formattedString)
{
// Define a regular expression pattern to match the nanoseconds part with exactly 7 digits.
string pattern = @"(\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{7})\d+Z";
// Check if the input matches the pattern.
if (!Regex.IsMatch(input, pattern))
{
formattedString = null;
return false;
}
// Input doesn't have 7 nanoseconds, so we truncate or pad it to have exactly 7 nanoseconds.
Match match = Regex.Match(input, pattern);
if (match.Success)
{
string nanosecondsPart = match.Groups[1].Value;
formattedString = $"{nanosecondsPart}Z";
return true;
}
else
{
// Invalid input, handle accordingly (throw an exception or return a default value).
throw new ArgumentException("Invalid DateTime format");
}
}
}
elgonzo
The DateTime type only support a precision out 7 digits in the micro/milli/nanos component of a DateTime string. So, by default the behavior of .net is to take a string like above and convert/round it to the next hour. It would turn into "2023-09-13T17:00:00" which is problematic. This can be resolved from the service side of course, and have the service return less precision, but in some cases that may not be possible if you don't own the service.
Given this is an ISO converter, I would suggest that it handle this scenario, and trim the micro/milli/nanos component down to 7, and convert it to a DateTime object to the max precision .net allows.