链接器为什么看不到我的（定义明确的）外部对象？

Question

I have a class with a header and a .cpp file. I declare my functions in the header, and define them in the .cpp file, as you would.

Header:

#pragma once

// my #includes 

class CDNAGenerator
{
private:
    // stuff 
public:
    CDNAGenerator(int, int);
    ~CDNAGenerator();

    void FilterMeasurementsForOutliers(std::vector<double>& measurement_values);

    // plenty more things

};

CPP:

CDNAGenerator::CDNAGenerator( int genes, int chromosomes )
{
    // constructor code
}

void CDNAGenerator::FilterMeasurementsForOutliers(std::vector<double>& measurement_values)
{
    // function code
}

Then, from a separate project in the same solution I reference the .h file (but not the .cpp - that seems to lead to multiple definition errors):

#include "..\CalibrationTool\DNAGenerator.h"

And call those functions:

CDNAGenerator* dnaGenerator = new CDNAGenerator(30, 0);
dnaGenerator->FilterMeasurementsForOutliers(values);

But I get unresolved external errors for CDNAGenerator::CDNAGenerator(int, int) and for CDNAGenerator::FilterMeasurementsForOutliers(class std::vector > &)

I thought that I had hooked everything up correctly, so can anyone suggest why I would be getting this linker error?

Answer 1

将CPP文件添加到项目

Answer 2

What compiler are you using? Gcc (mingw) does'n supprort #pragma once Use code guards to avoid 'multiple definitions'.

#ifndef MYCLASS_H
#define MYCLASS_H
class MyClass {
...
}
#endif