[英]New C++ Mongo driver: how to see type and how to get string value
I've got two questions that I cannot find an answer for in the tutorial.我有两个问题在教程中找不到答案。
I get a document and then an element from the doc like this:我从文档中获取一个文档,然后像这样获取一个元素:
bsoncxx::document::element e = doc["id"];
if (!e || e.type() != bsoncxx::type::k_int32) return ERROR;
int id = e.get_int32();
Is there a way to get a string value for the type, for debugging purposes?有没有办法获取该类型的字符串值,以用于调试目的? Like:
喜欢:
std::cout << e.type() << std::endl;
(which doesn't work) (这不起作用)
The second question is how to convert the utf8 type value into a std::string.第二个问题是如何将utf8类型值转换为std::string。 This doesn't work:
这不起作用:
e = doc["name"];
if (!e || e.type() != bsoncxx::type::k_utf8) return ERROR;
string name = e.get_utf8().value;
Any tips?有小费吗?
#include <bsoncxx/types.hpp>
std::cout << bsoncxx::to_string(bsoncxx::types::b_utf8::type_id);
result: "utf8"结果:“utf8”
And these are type of bsoncxx这些是 bsoncxx 的类型
namespace types {
struct b_eod;
struct b_double;
struct b_utf8;
struct b_document;
struct b_array;
struct b_binary;
struct b_undefined;
struct b_oid;
struct b_bool;
struct b_date;
struct b_null;
struct b_regex;
struct b_dbpointer;
struct b_code;
struct b_symbol;
struct b_codewscope;
struct b_int32;
struct b_timestamp;
struct b_int64;
struct b_minkey;
struct b_maxkey;
class value;
} // namespace types
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