can I read from a json file and parse with this library?

[binaery-a]

Im trying to organize data in JSON and needed a library to use to parse JSON files. Is there example code that does that? Like how to read from a file and then parse and return what was inside?

[nlohmann]

This is all in the README.

[binaery-a]

I read the README, could you please point out where or what example code specifically? I am new to c++ so a lot of it is hard to find

[nlohmann]

Ok, I will add some FAQ sections.

Here is a complete example how to open a file and pretty-print it to stdout. It is also in the overview GIF.

#include <fstream>
#include <iostream>
#include <nlohmann/json.hpp>

using json = nlohmann::json;

int main()
{
    std::ifstream f("myjson.json");
    json j = json::parse(f);
    std::cout << j.dump(2) << std::endl;
}

[binaery-a]

Thank you, I appreciate the help and the quick response

[nlohmann]

Glad if I could help. If you want to support me and my work on this project, you can become a sponsor on GitHub, or used Paypal.

[binaery-a]

Hi again,

Im trying to parse a specific field such as "measured_resistance" : "30" for example using my own json file:

{ "test" : "string test", "time" : [0, 1], "measurements" : [ { "channel_1" : "string 1", "channel_2" : "string 2", "measured_resistance" : 30, "R_min" : 20, "R_max" : 40, "passing" : true } ] }

And I read this area of the "over worked documentation" line 274:

#### Read from iterator range
You can also parse JSON from an iterator range; that is, from any container accessible by iterators whose content is stored as contiguous byte sequence, for instance a `std::vector<std::uint8_t>`:
```cpp
std::vector<std::uint8_t> v = {'t', 'r', 'u', 'e'};
json j = json::parse(v.begin(), v.end());

You may leave the iterators for the range [begin, end):

std::vector<std::uint8_t> v = {'t', 'r', 'u', 'e'};
json j = json::parse(v);

Is this a good place to start and implement into my own code to parse a specific field? If not, can I get pointed in the right direction? Or how do you recommend I go about this?

[nlohmann]

See #2295 for examples. Also the README file has some examples.

[binaery-a]

Okay, I will take a look at that. Thank you!