Error Code Return

[dhruveshg]

• No error code is returned and it crashes if the "key" is not found. I am new to this library, am I missing something? Could it return error code, or the only way to avoid crashing is to use exception handling?

json jProfile;
std::ifstream f(profileFile);
f >> jProfile;
jProfile.at("CONFIG").at(std::to_string(1)).get_to(configFileName);

[gregmarr]

If you don't know if the keys you are looking for are there, you either need to check first, using things like find(), or use the value() functions that take default values to return if the element is not found.

[RPGillespie6]

.at() throws an json::out_of_range if the key is not found. Also, this code with throw json::parse_error if profileFile is not valid json. You should wrap the whole thing with:

try {
    json jProfile;
    std::ifstream f(profileFile);
    f >> jProfile;
    jProfile.at("CONFIG").at(std::to_string(1)).get_to(configFileName);
} catch (json::exception & ex) {
    cout << "Uh oh, I messed up: " << ex.what() << endl;
}

If you don't want to do exception handling, then you have to do:

if (jProfile.count("CONFIG") && jProfile["CONFIG"].count("1"))
   jProfile.at("CONFIG").at(std::to_string(1)).get_to(configFileName);

[dhruveshg]

Thanks, I understand the implementation better now.