c++模板使用出错情况error LNK2019: unresolved external symbol "public: float __thiscall Compare<float>::min(void)" (?min@?$Compare@M@@QAEMXZ) referenced in function _main

将类模板在头文件中定义，类的成员函数在头文件中声明，头文件中只留下接口，函数的实现在另一个.cpp文件中，这样编译出来错误error LNK2019: unresolved external symbol "public: float __thiscall Compare<float>::min(void)" (?min@?$Compare@M@@QAEMXZ) referenced in function _main。将实现与接口全部在头文件中实现编译就成功了。

error：

class.h

#include<iostream>
#include<cmath>
#include<iomanip>
#include<conio.h>
#include<string>
using namespace std;

template<class T>
class Compare
{
public:
Compare(T x,T y):a(x),b(y){};
T max();
T min();
private:
T a;
T b;
};

 

class.cpp

#include"class.h"

template<class T>
T Compare<T>::max( )
{
return (a>=b)?a:b;
}

template<class T>
T Compare<T>::min( )
{
return (a<=b)?a:b;
}

 

right:

#include<iostream>
#include<cmath>
#include<iomanip>
#include<conio.h>
#include<string>
using namespace std;

template<class T>
class Compare
{
public:
Compare(T x,T y):a(x),b(y){};
T max();
T min();
private:
T a;
T b;
};

template<class T>
T Compare<T>::max( )
{
return (a>=b)?a:b;
}

template<class T>
T Compare<T>::min( )
{
return (a<=b)?a:b;
}