json/api/basic_json/to_bon8.md

nlohmann::basic_json::to_bon8

// (1)
static std::vector<std::uint8_t> to_bon8(const basic_json& j);

// (2)
static void to_bon8(const basic_json& j, detail::output_adapter<std::uint8_t> o);
static void to_bon8(const basic_json& j, detail::output_adapter<char> o);

Serializes a given JSON value j to a byte vector using the BON8 (Binary Object Notation 8) serialization format. BON8 is a compact binary serialization format that stores strings as UTF-8 without a length prefix.

1. Returns a byte vector containing the BON8 serialization.
2. Writes the BON8 serialization to an output adapter.

The exact mapping and its limitations are described on a dedicated page.

Parameters

j (in)

JSON value to serialize

o (in)

output adapter to write serialization to

Return value

1. BON8 serialization as a byte vector
2. (none)

Exception safety

Strong guarantee: if an exception is thrown, there are no changes in the JSON value j, which is never modified. With (2), the bytes written before the exception remain in the output adapter.

Exceptions

• Throws out_of_range.407 if j contains an unsigned integer above 9223372036854775807, which BON8 cannot represent
• Throws type_error.316 if j contains a string that is not valid UTF-8

Complexity

Linear in the size of the JSON value j.

Examples

??? example

The example shows the serialization of a JSON value to a byte vector in BON8 format.
 
```cpp
--8<-- "examples/to_bon8.cpp"
```

Output:

```json
--8<-- "examples/to_bon8.output"
```

See also

• from_bon8 create a JSON value from an input in BON8 format
• to_cbor create a CBOR serialization of a JSON value
• to_msgpack create a MessagePack serialization of a JSON value
• to_bson create a BSON serialization of a JSON value
• to_ubjson create a UBJSON serialization of a JSON value
• to_bjdata create a BJData serialization of a JSON value

Version history

• Added in version 3.13.0.