json/api/basic_json/to_cbor.md

nlohmann::basic_json::to_cbor

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

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

Serializes a given JSON value j to a byte vector using the CBOR (Concise Binary Object Representation) serialization format. CBOR is a binary serialization format that aims to be more compact than JSON itself, yet more efficient to parse.

1. Returns a byte vector containing the CBOR serialization.
2. Writes the CBOR 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. CBOR serialization as a byte vector
2. (none)

Exception safety

Strong guarantee: if an exception is thrown, there are no changes in the JSON value.

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 CBOR format.
 
```cpp
--8<-- "examples/to_cbor.cpp"
```

Output:

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

See also

• from_cbor create a JSON value from an input in CBOR format
• 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 2.0.9.
• Compact representation of floating-point numbers added in version 3.8.0.