json/doc/examples/get_to.cpp

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#include <iostream>
#include <unordered_map>
#include <nlohmann/json.hpp>
using json = nlohmann::json;
int main()
{
// create a JSON value with different types
json json_types =
{
{"boolean", true},
{
"number", {
{"integer", 42},
{"floating-point", 17.23}
}
},
{"string", "Hello, world!"},
{"array", {1, 2, 3, 4, 5}},
{"null", nullptr}
};
bool v1;
int v2;
short v3;
float v4;
int v5;
std::string v6;
std::vector<short> v7;
std::unordered_map<std::string, json> v8;
// use explicit conversions
json_types["boolean"].get_to(v1);
json_types["number"]["integer"].get_to(v2);
json_types["number"]["integer"].get_to(v3);
json_types["number"]["floating-point"].get_to(v4);
json_types["number"]["floating-point"].get_to(v5);
json_types["string"].get_to(v6);
json_types["array"].get_to(v7);
json_types.get_to(v8);
// print the conversion results
std::cout << v1 << '\n';
std::cout << v2 << ' ' << v3 << '\n';
std::cout << v4 << ' ' << v5 << '\n';
std::cout << v6 << '\n';
for (auto i : v7)
{
std::cout << i << ' ';
}
std::cout << "\n\n";
for (auto i : v8)
{
std::cout << i.first << ": " << i.second << '\n';
}
}