我正在使用Visual Studio 2015创建Win32项目。我尝试使用chrono库，但它说找不到。我在控制台项目中使用chrono库测试了代码，但该代码在控制台项目中有效，但在Win32项目中不起作用。
#include <chrono>
...
using namespace std::chrono;
LocalDriveHeader header;
auto durnow = system_clock::now ().time_since_epoch ();
header.version = VERSION;
header.flags = 0x0000;
header.sector_size = sector_size;
header.early_time = chrono::duration_cast <milliseconds> (durnow).count ();
...
=== EDIT ===
是的，我确实包含了chrono header 。
该项目是带有预编译头的Win32项目。
c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(123): error C2039: 'chrono': is not a member of 'std'
1> c:\program files (x86)\microsoft visual studio 14.0\vc\include\memory(1175): note: see declaration of 'std'
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(123): error C2871: 'chrono': a namespace with this name does not exist
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(126): error C2653: 'system_clock': is not a class or namespace name
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(126): error C3861: 'now': identifier not found
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(126): error C2228: left of '.time_since_epoch' must have class/struct/union
1> c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(126): note: type is 'unknown-type'
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(131): error C2653: 'chrono': is not a class or namespace name
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(131): error C2065: 'duration_cast': undeclared identifier
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(131): error C2065: 'milliseconds': undeclared identifier
1>c:\users\eunbin\documents\visual studio 2015\projects\gamgeum\gamgeum\container.cpp(131): error C3536: 'durnow': cannot be used before it is initialized
最佳答案
您的文件顶部可能缺少#include <chrono>。您需要此#include才能访问std::chrono命名空间。
关于c++ - 错误C2039: 'chrono':不是 'std'的成员，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/39218154/