1、前置条件需要安装好MongoDB的驱动（mongocxx），mongo跑起来。
2、项目包含相关头文件和库，例如：
INCLUDEPATH += "/usr/local/include/mongocxx/v_noabi"
INCLUDEPATH += "/usr/local/include/bsoncxx/v_noabi"
LIBS += -L/usr/local/lib/ -lbsoncxx -lmongocxx
3、C++代码如下，已经很精简，不废话解释了：
#include <iostream> #include <bsoncxx/builder/stream/document.hpp> #include <bsoncxx/json.hpp> #include <mongocxx/client.hpp> #include <mongocxx/instance.hpp>
int main(int, char**) { mongocxx::instance inst{}; mongocxx::client conn{mongocxx::uri{"mongodb://testuser:testpwd@127.0.0.1:27018/testdb"}}; //注意在Mongodb3.X版本中需要确保testdb存在，并且testuser:testpwd是在testdb库中进行授权的用户
bsoncxx::builder::stream::document document{}; auto collection = conn["testdb"]["testcollection"]; std::cout<<"type:-----------------------------------"<<typeid(collection).name()<<std::endl; decltype(collection) col=collection; std::cout<<"type:-----------------------------------"<<typeid(col).name()<<std::endl; document <<"hello" << "world"
<<"name" <<"csr"
<<"No" <<34
<<"3D" <<bsoncxx::builder::stream::open_array <<48<<32.123456789<<47
<<bsoncxx::builder::stream::close_array <<"friends" <<bsoncxx::builder::stream::open_array <<"zhangsan"<<"lisi"<<"wangwu"
<<bsoncxx::builder::stream::close_array <<"address0" <<bsoncxx::builder::stream::open_document <<"city"<<"shenzhen"
<<"nation"<<"china"
<<"phone"<<13524531211
<<bsoncxx::builder::stream::close_document /*<<bsoncxx::builder::stream::finalize*/; std::cout<<"the document:"<<bsoncxx::to_json(document) << std::endl; bsoncxx::builder::stream::document subdocument{}; subdocument << "city" << "sz"<<"nation"<<"china"<<"pos"<<525346; document<<"address"<<subdocument; std::cout<<"the document after subdoc:"<<bsoncxx::to_json(document) << std::endl; //插入文档
collection.insert_one(document.view()); collection.insert_one(document.view()); collection.insert_one(document.view()); //全部罗列文档
auto cursor = collection.find({}); for (auto&& doc : cursor) { std::cout << bsoncxx::to_json(doc) << std::endl; } std::cout<<"\n after insert_one three times count:"<<collection.count({})<<std::endl; //删除文档
collection.delete_one(document.view()); std::cout<<"\n after delete_one once count:"<<collection.count({})<<std::endl; // collection.delete_many(document.view()); // std::cout<<"\n after delete_many once count:"<<collection.count({})<<std::endl; //罗列全部数据库
auto dbcur = conn.list_databases(); for(auto && db:dbcur){ std::cout<<bsoncxx::to_json(db)<<std::endl; } std::cout<<std::endl; std::cout<<std::endl; // collection =conn.database("eos").collection("transaction_traces"); //查找文档 // cursor = collection.find({}); //按普通key-volue查找 // cursor = collection.find((bsoncxx::builder::basic::make_document(bsoncxx::builder::basic::kvp("actor", "token")))); // cursor = collection.find((bsoncxx::builder::basic::make_document(bsoncxx::builder::basic::kvp("block_num", 4171818)))); //按完整数组查找
bsoncxx::builder::stream::document finddocument{}; // finddocument<<"3D" <<bsoncxx::builder::stream::open_array // <<48<<32.123456789<<47 // <<bsoncxx::builder::stream::close_array; //按数组的一部分内容查找 // finddocument<<"3D" <<48; //嵌套文档查找
finddocument<<"address0" <<bsoncxx::builder::stream::open_document <<"city"<<"shenzhen"
<<"nation"<<"china"
<<"phone"<<13524531211
<<bsoncxx::builder::stream::close_document; cursor = collection.find(finddocument.view()); // bsoncxx::builder::stream::document filter_builder; // filter_builder << "stime" << open_document // << "$lt" << bsoncxx::types::b_date(std::chrono::system_clock::now()) // << close_document // << "stime" << open_document // << "$gt" << bsoncxx::types::b_date(std::chrono::system_clock::now() - std::chrono::seconds{ 600 }) // << close_document // << "iscancel" << 0 // << "gid" << strGId; // //相当于sql语句：SELECT * FROM bak__user_order WHERE gid=“2423seef” // // and iscancel=0 // // AND add_time < 1514233574 // // and add_time >=1514233574
int flag=0; for(auto&& doc : cursor/*collection.find(bsoncxx::builder::basic::make_document(bsoncxx::builder::basic::kvp("block_num", 3120204)))*/){ // bsoncxx::to_json(doc);
std::cout<<++flag<<"(find):"<<std::endl<<bsoncxx::to_json(doc) << std::endl; } if(flag==0) std::cout<<"\nnot found!!!"<<std::endl; std::cout<<"count:"<<collection.count({})<<std::endl; }