1
0
mirror of https://github.com/nlohmann/json synced 2024-12-10 11:40:06 +00:00
nlohmannjson/doc/examples/is_null.cpp
Niels Lohmann 504012a3db
📝 cleanup after #650
As <iostream> is not included in json.hpp any more, all code examples need to include <iostream> now.
2017-07-09 11:51:38 +02:00

29 lines
842 B
C++

#include <iostream>
#include "json.hpp"
using json = nlohmann::json;
int main()
{
// create JSON values
json j_null;
json j_boolean = true;
json j_number_integer = 17;
json j_number_unsigned_integer = 12345678987654321u;
json j_number_float = 23.42;
json j_object = {{"one", 1}, {"two", 2}};
json j_array = {1, 2, 4, 8, 16};
json j_string = "Hello, world";
// call is_null()
std::cout << std::boolalpha;
std::cout << j_null.is_null() << '\n';
std::cout << j_boolean.is_null() << '\n';
std::cout << j_number_integer.is_null() << '\n';
std::cout << j_number_unsigned_integer.is_null() << '\n';
std::cout << j_number_float.is_null() << '\n';
std::cout << j_object.is_null() << '\n';
std::cout << j_array.is_null() << '\n';
std::cout << j_string.is_null() << '\n';
}