mirror of
https://github.com/nlohmann/json.git
synced 2024-12-12 03:49:22 +08:00
60 lines
1.1 KiB
Markdown
60 lines
1.1 KiB
Markdown
|
# basic_json::find
|
||
|
|
||
|
```cpp
|
||
|
template<typename KeyT>
|
||
|
iterator find(KeyT&& key);
|
||
|
|
||
|
template<typename KeyT>
|
||
|
const_iterator find(KeyT&& key) const
|
||
|
```
|
||
|
|
||
|
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
|
||
|
object, `end()` is returned.
|
||
|
|
||
|
## Template parameters
|
||
|
|
||
|
`KeyT`
|
||
|
: A type for an object key.
|
||
|
|
||
|
## Parameters
|
||
|
|
||
|
`key` (in)
|
||
|
: key value of the element to search for.
|
||
|
|
||
|
## Return value
|
||
|
|
||
|
Iterator to an element with key equivalent to `key`. If no such element is found or the JSON value is not an object,
|
||
|
past-the-end (see `end()`) iterator is returned.
|
||
|
|
||
|
## Exception safety
|
||
|
|
||
|
Strong exception safety: if an exception occurs, the original value stays intact.
|
||
|
|
||
|
## Complexity
|
||
|
|
||
|
Logarithmic in the size of the JSON object.
|
||
|
|
||
|
## Notes
|
||
|
|
||
|
This method always returns `end()` when executed on a JSON type that is not an object.
|
||
|
|
||
|
## Example
|
||
|
|
||
|
??? example
|
||
|
|
||
|
The example shows how `find()` is used.
|
||
|
|
||
|
```cpp
|
||
|
--8<-- "examples/find__key_type.cpp"
|
||
|
```
|
||
|
|
||
|
Output:
|
||
|
|
||
|
```json
|
||
|
--8<-- "examples/find__key_type.output"
|
||
|
```
|
||
|
|
||
|
## Version history
|
||
|
|
||
|
- Added in version 1.0.0.
|