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### jsoncons::staj_array_iterator
```cpp
#include <jsoncons/staj_iterator.hpp>
template<
typename T,
typename Json
>
class staj_array_iterator
```
A `staj_array_iterator` is an [InputIterator](https://en.cppreference.com/w/cpp/named_req/InputIterator) that
accesses the individual stream events from a [staj_cursor](staj_cursor.md) and, provided that when it is constructed
the current stream event has type `staj_event_type::begin_array`, it retrieves the elements of the JSON array
as items of type `T`. If when it is constructed the current stream event does not have type `staj_event_type::begin_array`,
it becomes equal to the default-constructed iterator.
#### Member types
Member type |Definition
------------------------------------|------------------------------
`char_type`|Json::char_type
`value_type`|`T`
`difference_type`|`std::ptrdiff_t`
`pointer`|`value_type*`
`reference`|`value_type&`
`iterator_category`|[std::input_iterator_tag](https://en.cppreference.com/w/cpp/iterator/iterator_tags)
#### Constructors
staj_array_iterator() noexcept; (1)
staj_array_iterator(staj_array_view<T, Json>& view); (2)
staj_array_iterator(staj_array_view<T, Json>& view,
std::error_code& ec); (3)
(1) Constructs the end iterator
(2) Constructs a `staj_array_iterator` that refers to the first element of the array
following the current stream event `begin_array`. If there is no such element,
returns the end iterator. If a parsing error is encountered, throws a
[ser_error](ser_error.md).
(3) Constructs a `staj_array_iterator` that refers to the first member of the array
following the current stream event `begin_array`. If there is no such element,
returns the end iterator. If a parsing error is encountered, returns the end iterator
and sets `ec`.
#### Member functions
const T& operator*() const
const T* operator->() const
staj_array_iterator& operator++()
staj_array_iterator& increment(std::error_code& ec)
staj_array_iterator operator++(int)
Advances the iterator to the next array element.
#### Non-member functions
template <typename T,typename Json>
bool operator==(const staj_array_iterator<T, Json>& a, const staj_array_iterator<T, Json>& b);
template <typename Json,typename T>
bool operator!=(const staj_array_iterator<T, Json>& a, const staj_array_iterator<T, Json>& b);
### Examples
#### Iterate over a JSON array, returning json values
```cpp
const std::string example = R"(
[
{
"employeeNo" : "101",
"name" : "Tommy Cochrane",
"title" : "Supervisor"
},
{
"employeeNo" : "102",
"name" : "Bill Skeleton",
"title" : "Line manager"
}
]
)";
int main()
{
std::istringstream is(example);
json_stream_cursor cursor(is);
auto view = staj_array<json>(cursor);
for (const auto& j : view)
{
std::cout << pretty_print(j) << "\n";
}
std::cout << "\n\n";
}
```
Output:
```
{
"employeeNo": "101",
"name": "Tommy Cochrane",
"title": "Supervisor"
}
{
"employeeNo": "102",
"name": "Bill Skeleton",
"title": "Line manager"
}
```
#### Iterate over the JSON array, returning employee values
```cpp
namespace ns {
struct employee
{
std::string employeeNo;
std::string name;
std::string title;
};
} // namespace ns
JSONCONS_ALL_MEMBER_TRAITS(ns::employee, employeeNo, name, title)
int main()
{
std::istringstream is(example);
json_stream_cursor cursor(is);
auto view = staj_array<ns::employee>(cursor);
for (const auto& val : view)
{
std::cout << val.employeeNo << ", " << val.name << ", " << val.title << "\n";
}
std::cout << "\n\n";
}
```
Output:
```
101, Tommy Cochrane, Supervisor
102, Bill Skeleton, Line manager
```
|
