I need to search for an element in a json file using the jsoncpp library. I can't wrap my head around how to get to the most inner array... Any thoughts?
{
"key": int,
"array1": [
{
"key": int,
"array2": [
{
"key": int,
"array3": [
{
"needed_key": int
}
]
}
]
}
]
}
Up until now I tried something like this:
const Json::Value& array1 = root["array1"];
for (size_t i = 0; i < array1.size(); i )
{
const Json::Value& array2 = array1["array2"];
for (size_t j = 0; j < array2.size(); j )
{
const Json::Value& array3 = array2["array3"];
for (size_t k = 0; k < array3.size(); k )
{
std::cout << "Needed Key: " << array3["needed_key"].asInt();
}
}
}
But it throws:
JSONCPP_NORETURN void throwLogicError(String const& msg) {
throw LogicError(msg);
}
CodePudding user response:
You can't access array2
with array1["array2"]
, since array1
contains an array of objects, not an object, so you should get array2
with an index i
, array1[i]["array2"]
instead.
The following code works for me:
const Json::Value &array1 = root["array1"];
for (int i = 0; i < array1.size(); i ) {
const Json::Value &array2 = array1[i]["array2"];
for (int j = 0; j < array2.size(); j ) {
const Json::Value &array3 = array2[j]["array3"];
for (int k = 0; k < array3.size(); k ) {
std::cout << "Needed Key: " << array3[k]["needed_key"].asInt();
}
}
}
The output looks like:
Needed Key: 4