61154547d1
Conflicts: doc/mkdocs/docs/api/basic_json/contains.md doc/mkdocs/docs/api/basic_json/find.md include/nlohmann/json.hpp single_include/nlohmann/json.hpp test/src/unit-regression2.cpp
66 lines
1.4 KiB
Markdown
66 lines
1.4 KiB
Markdown
# <small>nlohmann::basic_json::</small>find
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```cpp
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template<typename KeyT>
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iterator find(const KeyT& key);
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template<typename KeyT>
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const_iterator find(const KeyT& key) const;
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```
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Finds an element in a JSON object with key equivalent to `key`. If the element is not found or the JSON value is not an
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object, `end()` is returned.
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## Template parameters
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`KeyT`
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: A type for an object key that is less-than comparable with `string_t`. This can also be a string literal or a string
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view (C++17).
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## Parameters
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`key` (in)
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: key value of the element to search for.
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## Return value
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Iterator to an element with key equivalent to `key`. If no such element is found or the JSON value is not an object,
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past-the-end (see `end()`) iterator is returned.
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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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## Complexity
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Logarithmic in the size of the JSON object.
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## Notes
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This method always returns `end()` when executed on a JSON type that is not an object.
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## Examples
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??? example
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The example shows how `find()` is used.
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```cpp
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--8<-- "examples/find__key_type.cpp"
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```
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Output:
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```json
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--8<-- "examples/find__key_type.output"
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```
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## See also
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- [contains](contains.md) checks whether a key exists
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## Version history
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- Added in version 1.0.0.
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- Extended template `KeyT` in version 3.10.5 to also support `std::string_view`.
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