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### jsoncons::json
```cpp
#include <jsoncons/json.hpp>
typedef basic_json<char,
Policy = sorted_policy,
Allocator = std::allocator<char>> json
```
The class `json` is an instantiation of the [basic_json](basic_json.md) class template that uses `char` as the character type.
The order of an object's name/value pairs is not preserved, they are sorted alphabetically by name.
If you want to preserve the original insertion order, use [ojson](ojson.md) instead.
### See also
[ojson](ojson.md) constructs a utf8 character json value that preserves the original insertion order of an object's name/value pairs
[wjson](wjson.md) constructs a wide character json value that sorts name-value members alphabetically
[wojson](wojson.md) constructs a wide character json value that preserves the original insertion order of an object's name/value pairs
### Examples
#### Accessors and defaults
```cpp
json j;
j["field1"] = 1;
j["field3"] = "Toronto";
double x1 = obj.contains("field1") ? j["field1"].as<double>() : 10.0;
double x2 = obj.contains("field2") ? j["field2"].as<double>() : 20.0;
std::string x3 = obj.get_value_or<std::string>("field3","Montreal");
std::string x4 = obj.get_value_or<std::string>("field4","San Francisco");
std::cout << "x1=" << x1 << '\n';
std::cout << "x2=" << x2 << '\n';
std::cout << "x3=" << x3 << '\n';
std::cout << "x4=" << x4 << '\n';
```
Output:
```cpp
x1=1
x2=20
x3=Toronto
x4=San Francisco
```
#### Nulls
```cpp
json j;
j["field1"] = json::null();
std::cout << j << '\n';
```
Output:
```json
{"field1":null}
```
#### Constructing json structures
```cpp
json doc;
doc["persons"] = json(json_array_arg);
json person;
person["first_name"] = "John";
person["last_name"] = "Smith";
person["birth_date"] = "1972-01-30";
json address;
address["city"] = "Toronto";
address["country"] = "Canada";
person["address"] = std::move(address);
doc["persons"].push_back(std::move(person));
std::cout << pretty_print(doc) << '\n';
```
Output:
```cpp
{
"persons":
[
{
"address":
{
"city":"Toronto",
"country":"Canada"
},
"birth_date":"1972-01-30",
"first_name":"John",
"last_name":"Smith"
}
]
}
```
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