static int ToJsonCore(byte[] bytes, int offset, StringBuilder builder) { var readSize = 0; var type = MessagePackBinary.GetMessagePackType(bytes, offset); switch (type) { case MessagePackType.Integer: var code = bytes[offset]; if (MessagePackCode.MinNegativeFixInt <= code && code <= MessagePackCode.MaxNegativeFixInt) { builder.Append(MessagePackBinary.ReadSByte(bytes, offset, out readSize)); } else if (MessagePackCode.MinFixInt <= code && code <= MessagePackCode.MaxFixInt) { builder.Append(MessagePackBinary.ReadByte(bytes, offset, out readSize)); } else if (code == MessagePackCode.Int8) { builder.Append(MessagePackBinary.ReadSByte(bytes, offset, out readSize)); } else if (code == MessagePackCode.Int16) { builder.Append(MessagePackBinary.ReadInt16(bytes, offset, out readSize)); } else if (code == MessagePackCode.Int32) { builder.Append(MessagePackBinary.ReadInt32(bytes, offset, out readSize)); } else if (code == MessagePackCode.Int64) { builder.Append(MessagePackBinary.ReadInt64(bytes, offset, out readSize)); } else if (code == MessagePackCode.UInt8) { builder.Append(MessagePackBinary.ReadByte(bytes, offset, out readSize)); } else if (code == MessagePackCode.UInt16) { builder.Append(MessagePackBinary.ReadUInt16(bytes, offset, out readSize)); } else if (code == MessagePackCode.UInt32) { builder.Append(MessagePackBinary.ReadUInt32(bytes, offset, out readSize)); } else if (code == MessagePackCode.UInt64) { builder.Append(MessagePackBinary.ReadUInt64(bytes, offset, out readSize)); } break; case MessagePackType.Boolean: builder.Append(MessagePackBinary.ReadBoolean(bytes, offset, out readSize) ? "true" : "false"); break; case MessagePackType.Float: var floatCode = bytes[offset]; if (floatCode == MessagePackCode.Float32) { builder.Append(MessagePackBinary.ReadSingle(bytes, offset, out readSize).ToString(System.Globalization.CultureInfo.InvariantCulture)); } else { builder.Append(MessagePackBinary.ReadDouble(bytes, offset, out readSize).ToString(System.Globalization.CultureInfo.InvariantCulture)); } break; case MessagePackType.String: WriteJsonString(MessagePackBinary.ReadString(bytes, offset, out readSize), builder); break; case MessagePackType.Binary: builder.Append("\"" + Convert.ToBase64String(MessagePackBinary.ReadBytes(bytes, offset, out readSize)) + "\""); break; case MessagePackType.Array: { var length = MessagePackBinary.ReadArrayHeaderRaw(bytes, offset, out readSize); var totalReadSize = readSize; offset += readSize; builder.Append("["); for (int i = 0; i < length; i++) { readSize = ToJsonCore(bytes, offset, builder); offset += readSize; totalReadSize += readSize; if (i != length - 1) { builder.Append(","); } } builder.Append("]"); return(totalReadSize); } case MessagePackType.Map: { var length = MessagePackBinary.ReadMapHeaderRaw(bytes, offset, out readSize); var totalReadSize = readSize; offset += readSize; builder.Append("{"); for (int i = 0; i < length; i++) { // write key { var keyType = MessagePackBinary.GetMessagePackType(bytes, offset); if (keyType == MessagePackType.String || keyType == MessagePackType.Binary) { readSize = ToJsonCore(bytes, offset, builder); } else { builder.Append("\""); readSize = ToJsonCore(bytes, offset, builder); builder.Append("\""); } offset += readSize; totalReadSize += readSize; } builder.Append(":"); // write body { readSize = ToJsonCore(bytes, offset, builder); offset += readSize; totalReadSize += readSize; } if (i != length - 1) { builder.Append(","); } } builder.Append("}"); return(totalReadSize); } case MessagePackType.Extension: var extHeader = MessagePackBinary.ReadExtensionFormatHeader(bytes, offset, out readSize); if (extHeader.TypeCode == ReservedMessagePackExtensionTypeCode.DateTime) { var dt = MessagePackBinary.ReadDateTime(bytes, offset, out readSize); builder.Append("\""); builder.Append(dt.ToString("o", CultureInfo.InvariantCulture)); builder.Append("\""); } #if NETSTANDARD1_4 else if (extHeader.TypeCode == TypelessFormatter.ExtensionTypeCode) { int startOffset = offset; // prepare type name token offset += 6; var typeNameToken = new StringBuilder(); var typeNameReadSize = ToJsonCore(bytes, offset, typeNameToken); offset += typeNameReadSize; int startBuilderLength = builder.Length; if (extHeader.Length > typeNameReadSize) { // object map or array var typeInside = MessagePackBinary.GetMessagePackType(bytes, offset); if (typeInside != MessagePackType.Array && typeInside != MessagePackType.Map) { builder.Append("{"); } offset += ToJsonCore(bytes, offset, builder); // insert type name token to start of object map or array if (typeInside != MessagePackType.Array) { typeNameToken.Insert(0, "\"$type\":"); } if (typeInside != MessagePackType.Array && typeInside != MessagePackType.Map) { builder.Append("}"); } if (builder.Length - startBuilderLength > 2) { typeNameToken.Append(","); } builder.Insert(startBuilderLength + 1, typeNameToken.ToString()); } else { builder.Append("{\"$type\":\"" + typeNameToken.ToString() + "}"); } readSize = offset - startOffset; } #endif else { var ext = MessagePackBinary.ReadExtensionFormat(bytes, offset, out readSize); builder.Append("["); builder.Append(ext.TypeCode); builder.Append(","); builder.Append("\""); builder.Append(Convert.ToBase64String(ext.Data)); builder.Append("\""); builder.Append("]"); } break; case MessagePackType.Unknown: case MessagePackType.Nil: default: readSize = 1; builder.Append("null"); break; } return(readSize); }