json/api/basic_json/get_binary/index.md

nlohmann::basic_json::get_binary

binary_t& get_binary();

const binary_t& get_binary() const;

Returns a reference to the stored binary value.

Return value

Reference to binary value.

Exception safety

Strong exception safety: if an exception occurs, the original value stays intact.

Exceptions

Throws type_error.302 if the value is not binary

Complexity

Constant.

Examples

Example

The following code shows how to query a binary value.

#include <iostream>
#include <nlohmann/json.hpp>

using json = nlohmann::json;

int main()
{
    // create a binary vector
    std::vector<std::uint8_t> vec = {0xCA, 0xFE, 0xBA, 0xBE};

    // create a binary JSON value with subtype 42
    json j = json::binary(vec, 42);

    // output type and subtype
    std::cout << "type: " << j.type_name() << ", subtype: " << j.get_binary().subtype() << std::endl;
}

Output:

type: binary, subtype: 42

See also

• get get a value (explicit conversion)
• get_ref get a reference to the stored value

Version history

• Added in version 3.8.0.