demo.cs

using ProtoBuf;
using System;
using System.IO;

static class Funchelper
{
    static void Main()
    {
        var obj = new NotAForm();
        obj.DoTheThing();
    }

    public static byte[] HexStrTobyte(string hex)
    { // I'm guessing some code here...
        hex = hex.Replace(" ", "");
        var blob = new byte[hex.Length / 2];
        for (int i = 0; i < blob.Length; i++)
        {
            blob[i] = Convert.ToByte(hex.Substring(i * 2, 2), 16);
        }
        return blob;
    }

    public static string byteToHexStr(byte[] bytes)
    {
        string returnStr = "";
        if (bytes != null)
        {
            for (int i = 0; i < bytes.Length; i++)
            {
                returnStr += bytes[i].ToString("X2") + " ";//ToString("X2") 为C#中的字符串格式控制符
            }
        }
        return returnStr;
    }
}
class NotAForm
{
    public void DoTheThing() => button1_Click(this, EventArgs.Empty);

    private void button1_Click(object sender, EventArgs e)
    {
        string data = "ClgKCjE2NDMzMTAwMDISDkxvcmRjVmVqZ3dCYTRtGgAgATgBQABIAFiorbuY6KxeYNqdE2iF+AVw0O2S3aEueJygqMLngmGAAbLXy48GkAEAmAEAoAEAqAEDEAgYqIaZxbwuKiw3bUpoYmlUL29nM0trSkZ0T2duK3Rkcys2TG9OcFdoZzdGZUlnQmF4ZkgwPTINaHR0cHM6Ly8uY29tLzix18uPBkIGT25saW5lSAA=";
        byte[] data2 = System.Convert.FromBase64String(data);
        data = Funchelper.byteToHexStr(data2);

        Console.WriteLine(ProtobufDecode(data));

    }


    static string WriteTree(ProtoReader reader)
    {
        string JSONstring = null;
        JSONstring = "[";
        while (reader.ReadFieldHeader() > 0)
        {
            Console.WriteLine(reader.FieldNumber);
            Console.WriteLine(reader.WireType);
            switch (reader.WireType)
            {
                case WireType.String:
                    string dataStr = null;
                    byte[] dataByte = null;
                    dataByte = ProtoReader.AppendBytes(null, reader);
                    if (dataByte[0].ToString() == "10")
                    {
                        dataStr = Funchelper.byteToHexStr(dataByte);
                        dataStr = ProtobufDecode(dataStr);
                    }
                    else
                    {
                        dataStr = Convert.ToString(dataByte);
                    }

                    JSONstring += "{";
                    JSONstring += "\"" + "FieldNumber" + "\":\"" + reader.FieldNumber + "\",";
                    JSONstring += "\"" + "WireType" + "\":\"" + reader.WireType + "\",";
                    JSONstring += "\"" + "Value" + "\":\"" + dataStr + "\",";
                    JSONstring += "},";
                    break;
                case WireType.StartGroup:
                    // one of 2 sub-object formats
                    var tok = ProtoReader.StartSubItem(reader);
                    WriteTree(reader);
                    ProtoReader.EndSubItem(tok, reader);
                    break;
                default:
                    reader.SkipField();
                    break;
            }
        }
        char[] specialChars = new char[] { ',' };
        JSONstring = JSONstring.TrimEnd(specialChars);
        JSONstring += "]";
        return JSONstring;
    }

    static string ProtobufDecode(string checkHex)
    {
        byte[] data = Funchelper.HexStrTobyte(checkHex);
        using (var ms = new MemoryStream(data))
        {
            try
            {
                var test = ProtoReader.Create(ms, null, null);
                string datatest = WriteTree(test);
                return datatest;
            }
            catch { }

        }

        return System.Text.Encoding.ASCII.GetString(Funchelper.HexStrTobyte(checkHex));
    }
}