[Visual Studio] Error LNK2019, use C++ language, cooperate with Qt to develop serial communication interface

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I encountered this bug when I was working on this project: [Visual Studio] Developed a serial communication interface with C++ language and Qt .

question

When using C++ language and cooperating with Qt to develop the serial communication interface, the error code LNK2019 is reported.

Copy the error message so that others can retrieve my article when searching. The error message is as follows:

Severity Code Description Project File Line Suppressed Display Status
Error LNK2019 ??? "__declspec(dllimport) public: __cdecl QSerialPort::QSerialPort(class QObject *)" (_ imp ??0QSerialPort@@QEAA@PEAVQObject@@@Z), ?? “public: __cdecl GUI::GUI(class QWidget *)” (??0GUI@@QEAA@PEAVQWidget@@@Z) ??? GUI C:\Users\jicha\source\repos\GUI\GUI.obj 1

The screenshot of the error is as follows:

solution

A picture is better than the preface, and the solution should follow the picture below.

Note, don't forget to select other Modules required by the project. If you encounter similar problems in the future, you can solve them in the same way.

Finally, put another screenshot of the successful solution, hoping to help you.

Ref.

1. 1. Unresolved external symbol "__declspec(dllimport) const XXX::vftable"` 2. `Cannot define dllimport entity`
2. VS2017 uses QSerialPort to report LNK2019 error