Why is there an access violation on connecting to MongoDB from C++?

问题

When I try to run this little piece of code

#include <iostream>
#include <bsoncxx/builder/stream/document.hpp>
#include <bsoncxx/json.hpp>
#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>

int main(int argc, char **argv)
{
    mongocxx::client client{mongocxx::uri{}};
    mongocxx::database db = client["xyz"];
    std::cout << "Connected to xyz." << std::endl;
}

I always get this warning

Exception thrown at 0x00007FFF7815F1FD (libmongoc-1.0.dll) in Test.exe: 0xC0000005: Access violation writing location 0x0000000000000020.

Can someone help?

回答1:

I fixed it by adding

mongocxx::instance instance{};

as the first line of code in the main function.

来源：https://stackoverflow.com/questions/42191206/why-is-there-an-access-violation-on-connecting-to-mongodb-from-c