Configuration Value Converter for enum and List<T>

CaseInsensitiveEnumConverter.cs

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

    TEnum result;
    if (!Enum.TryParse((string)value, true, out result))
    {
      throw new InvalidOperationException("Invalid enum value");
    }

    return result;
  }
}