C#•2y ago

✅ How to serialize IEnumerable<T> to json?

I have following:

public IReadOnlyList<MessageQueueConsumeResultHeader>? Headers { get; init; }

public abstract class MessageQueueConsumeResultHeader
  {
    public abstract string Key { get; }

    public abstract byte[] GetValueBytes();

    public override string ToString()
    {
      return this.Key + " (" + string.Join<byte>(",", (IEnumerable<byte>) this.GetValueBytes()) + ")";
    }
  }

public IReadOnlyList<MessageQueueConsumeResultHeader>? Headers { get; init; }

public abstract class MessageQueueConsumeResultHeader
  {
    public abstract string Key { get; }

    public abstract byte[] GetValueBytes();

    public override string ToString()
    {
      return this.Key + " (" + string.Join<byte>(",", (IEnumerable<byte>) this.GetValueBytes()) + ")";
    }
  }

and I want to get following:

"
{
"Key": "GetValueBytes()",
...
}
"

how can I do it?

SWEETPONYOP•1/16/24, 11:45 AM

I can do this:

public static class MessageQueueConsumeResultHeaderExtensions
{
    public static string ToJson(this IReadOnlyList<MessageQueueConsumeResultHeader>? headers)
    {
        if (headers == null || headers.Count == 0)
        {
            return "{}";
        }

        var result = new StringBuilder();
        result.AppendLine("{");
        foreach (var header in headers)
        {
            result.AppendLine($"  \"{header.Key}\": \"{string.Join(",", header.GetValueBytes())}\",");
        }
        result.Length--; // Remove the trailing comma
        result.AppendLine("}");
        return result.ToString();
    }
}

public static class MessageQueueConsumeResultHeaderExtensions
{
    public static string ToJson(this IReadOnlyList<MessageQueueConsumeResultHeader>? headers)
    {
        if (headers == null || headers.Count == 0)
        {
            return "{}";
        }

        var result = new StringBuilder();
        result.AppendLine("{");
        foreach (var header in headers)
        {
            result.AppendLine($"  \"{header.Key}\": \"{string.Join(",", header.GetValueBytes())}\",");
        }
        result.Length--; // Remove the trailing comma
        result.AppendLine("}");
        return result.ToString();
    }
}

but it looks bad

が

がんばるかも•1/16/24, 11:53 AM

JsonConverter serializes dictionaries as key-value pairs just fine

が

がんばるかも•1/16/24, 11:53 AM

so perhaps make the collection type into a dictionary?

が

がんばるかも•1/16/24, 11:54 AM

cleaner way would be to write a custom converter otherwise

cap5lut•1/16/24, 12:00 PM

iirc

IEnumerable<byte>

IEnumerable<byte>

will be serialized into a json array of numbers,

byte[]

byte[]

will result in a base64 encoded string,
the proper answer is a custom converter

が

がんばるかも•1/16/24, 12:02 PM

no I meant something on the line of exposing

Headers

Headers

IReadOnlyDictionary<string, byte[]>

IReadOnlyDictionary<string, byte[]>

SSWEETPONY I can do this: ```cs public static class MessageQueueConsumeResultHeaderExtensio...

cap5lut•1/16/24, 12:03 PM

yeah, that would result in

"header1": "base64-encoded-byte-array"

"header1": "base64-encoded-byte-array"

, while

would be

"header1": "1,254,4,6,127"

"header1": "1,254,4,6,127"

が

がんばるかも•1/16/24, 12:04 PM

ahhh so they do want it as a comma-separated list of values

が

がんばるかも•1/16/24, 12:04 PM

why though

が

がんばるかも•1/16/24, 12:04 PM

you'd need a custom converter then

が

がんばるかも•1/16/24, 12:05 PM

why though

cap5lut•1/16/24, 12:06 PM

tbh i like neither variant

i would prefer a simple hex string without delimiters for such stuff, but i guess base64 is at least not that a** long

が

がんばるかも•1/16/24, 12:06 PM

hex string would get much longer than base64!

が

がんばるかも•1/16/24, 12:07 PM

and I don't think it really adds any benefit apart from being easy to parse, so... why?

cap5lut•1/16/24, 12:11 PM

i was working on a project for a long time where i had to write some test packets (had to do with reverse engineering a network protocol),
guess i got used to hex in json because of that

cap5lut•1/16/24, 12:12 PM

was a lot of fiddling around, adding similar packets (if it were stored binary i would have taken a hex editor for that), where u simply edited the description, some bytes and that was it

cap5lut•1/16/24, 12:14 PM

later the guy i did work together on that wrote a whole GUI tool and stored the whole thing as binary blob but also with some more helpful visualization on the data

ががんばるかも no I meant something on the line of exposing `Headers` as `IReadOnlyDictionary<s...

SWEETPONYOP•1/16/24, 12:29 PM

unfortunately I can't change IEnumerable to IReadOnlyDictionary catshy

hm maybe I can do smth like..
Headers.ToDictionary(header => header.Key, header => header.GetValueBytes())

SWEETPONYOP•1/16/24, 12:31 PM

var map = context.Headers?.ToDictionary(x => x.Key, x => x.GetValueBytes());
var result = JsonSerializer.Serialize(map);

var map = context.Headers?.ToDictionary(x => x.Key, x => x.GetValueBytes());
var result = JsonSerializer.Serialize(map);

が

がんばるかも•1/16/24, 12:36 PM

I would suggest using a custom converter

ががんばるかも I would suggest using a custom converter

SWEETPONYOP•1/16/24, 12:40 PM

smth like this: https://www.newtonsoft.com/json/help/html/CustomJsonConverter.htm?

が

がんばるかも•1/16/24, 12:40 PM

are you using S.T.Json?

TeBeCo•1/16/24, 12:40 PM

please use System.Text.Json and not Newtonsoft.Json

が

がんばるかも•1/16/24, 12:41 PM

https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/converters-how-to?pivots=dotnet-8-0

How to write custom converters for JSON serialization - .NET

Learn how to create custom converters for the JSON serialization classes that are provided in the System.Text.Json namespace.

SWEETPONYOP•1/16/24, 12:41 PM

ok, thanks!