Configuration Value Converter for enum and List<T>

PipeDelimitedFlaggedEnumConverter.cs

public class PipeDelimitedFlaggedEnumConverter<TEnum> : ConfigurationConverterBase where TEnum : struct
{
  public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
  {
    if (value == null)
    {
      throw new ArgumentNullException(nameof(value));
    }

    var segments = ((string)value).Split(new string[] { "|" }, StringSplitOptions.RemoveEmptyEntries);
    var converted = 0;
    foreach (var segment in segments)
    {
      TEnum result;
      if (!Enum.TryParse((string)segment, true, out result))
      {
        throw new InvalidOperationException($"Invalid enum value - {segment}");
      }

      converted += Convert.ToInt32(result);
    }

    return (TEnum)Enum.ToObject(typeof(TEnum), converted);
  }
}