<分区>
我有一个类模板，它将输出存储在数组中的对象列表。我收到以下错误，由于错误在 .obj 和 .exe 文件中，所以我很困惑错误是在哪里引起的。
1 unresolved externals (proj08.exe line 1)
unresolved external symbol "class std::basic_ostream > & __cdecl operator<<(class std::basic_ostream > &,class MyVector)" (??6@YAAAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AAV01@V?$MyVector@N@@@Z) referenced in function _main (porj08.obj line 1)
proj08.cpp
#include "stdafx.h"
#include <string>
#include "MyVector.h"
const double FRACTION = 0.5;
int main()
{
cout << "\nCreating a vector of doubles named Sam\n";
MyVector<double> sam;
cout << "\nPush 12 values into the vector.";
for (int i = 0; i < 12; i++)
sam.push_back(i + FRACTION);
cout << "\nHere is sam: ";
cout << sam;
cout << "\n---------------\n";
cout << "\nCreating an empty vector named joe";
MyVector<double> joe;
// test assignment
joe = sam;
cout << "\nHere is joe after doing an assignment:\n ";
cout << joe;
cout << "\n---------------\n";
// test the copy constructor
MyVector<double> bill = sam;
cout << "\nHere is bill after creating it using the copy constructor:\n ";
cout << bill;
cout << "\n---------------\n";
cout << endl;
system("PAUSE");
return 0;
}
MyVector.h
#pragma once
#include <iostream>
#include "stdafx.h"
using namespace std;
template <class T>
class MyVector
{
private:
int vectorSize;
int vectorCapacity;
T *vectorArray;
public:
MyVector() {
vectorArray = new T[10];
}
T size();
T capacity();
void clear();
void push_back(T n);
T at(int n);
friend ostream& operator<<(ostream& os, MyVector<T> vt);
MyVector<T> operator=(MyVector<T>&);
};
/*
* TEMPLATE FUNCTIONS
*/
//Return array size
template<class T>
T MyVector<T>::size()
{
return vectorSize;
}
// Return array capacity
template<class T>
T MyVector<T>::capacity()
{
return vectorCapacity;
}
// clear array values
template<class T>
void MyVector<T>::clear()
{
for (int i = 0; i < vectorSize; i++)
{
vectorArray[i] = '\0';
}
vectorSize = 0;
vectorCapacity = 2;
}
// Add number to array and double array size if needed
template<class T>
void MyVector<T>::push_back(T n)
{
int test = 100;
if (vectorCapacity > vectorSize)
{
vectorArray[vectorSize] = n;
vectorSize++;
}
else {
if (vectorCapacity == 0) {
vectorArray = new T[4];
vectorArray[0] = n;
vectorCapacity = 4;
vectorSize++;
}
else {
int newCapacity = vectorCapacity * 2;
// Dynamically allocate a new array of integers what is somewhat larger than the existing array.An algorithm that is often used is to double the size of the array.
int *tempArray = new int[newCapacity];
// Change capacity to be the capacity of the new array.
vectorCapacity = newCapacity;
// Copy all of the numbers from the first array into the second, in sequence.
for (int i = 0; i < MyVector::size(); i++)
{
tempArray[i] = vectorArray[i];
}
delete[] vectorArray;
vectorArray = new T[newCapacity];
for (int i = 0; i < MyVector::size(); i++)
{
vectorArray[i] = tempArray[i];
}
delete[] tempArray;
// Add the new element at the next open slot in the new array.
vectorArray[vectorSize] = n;
// Increment the size;
vectorSize++;
}
}
}
// Return Value and given point in array
template<class T>
T MyVector<T>::at(int n)
{
return vectorArray[n];
}
// Set one vector to equil another
template<class T>
MyVector<T> MyVector<T>::operator=(MyVector<T>& right) {
if (vectorCapacity < right.vectorCapacity) {
if (vectorCapacity != 0)
delete[] vectorArray;
vectorArray = new T[right.vectorCapacity];
vectorCapacity = right.vectorCapacity;
}
vectorSize = right.size();
// Assign values from left to right
for (int i = 0; i < vectorSize; i++)
{
vectorArray[i] = right.at(i);
}
return *this;
}
// Cout Vector
template<class T>
ostream& operator << (ostream& os, MyVector<T> vt)
{
T size = vt.size();
for (T i = 0; i < size; i++) {
os << "index " << i << " is " << vt.at(i) << endl;
}
return os;
}