71 lines
1.5 KiB
Markdown
71 lines
1.5 KiB
Markdown
# <small>nlohmann::basic_json::</small>get_binary
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```cpp
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binary_t& get_binary();
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const binary_t& get_binary() const;
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```
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Returns a reference to the stored binary value.
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## Return value
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Reference to binary value.
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## Exception safety
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Strong exception safety: if an exception occurs, the original value stays intact.
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## Exceptions
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Throws [`type_error.302`](../../home/exceptions.md#jsonexceptiontype_error302) if the value is not binary
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## Complexity
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Constant.
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## Examples
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??? example
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The following code shows how to query a binary value.
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```cpp
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#include <iostream>
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#include <nlohmann/json.hpp>
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using nlohmann::json;
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int main()
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{
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// create a binary vector
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std::vector<std::uint8_t> vec = {0xCA, 0xFE, 0xBA, 0xBE};
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// create a binary JSON value with subtype 42
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json j = json::binary(vec, 42);
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// output type and subtype
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std::cout << "type: " << j.type_name() << ", subtype: " << j.get_binary().subtype() << '\n';
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}
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```
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Output:
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```json
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type: binary, subtype: 42
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```
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## See also
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- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
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- [`binary`](binary.md) - create a binary value
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- [`is_binary`](is_binary.md) - check whether a value is binary
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- [`get`](get.md) - get a value (explicit conversion)
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- [`get_ref`](get_ref.md) - get a reference to the stored value
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## Version history
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- Added in version 3.8.0.
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