关于模板：C ++不断收到错误LNK2019：未解析的外部符号

C++ keep getting error LNK2019: unresolved external symbol

本问题已经有最佳答案，请猛点这里访问。

我试着用谷歌搜索这个，但总是会遇到不同的问题。当我试图编译这个程序时，我得到了3个未解决的外部问题：

1
2
3

1>main.obj : error LNK2019: unresolved external symbol"public: __thiscall DynIntStack<char>::~DynIntStack<char>(void)" (??1?$DynIntStack@D@@QAE@XZ) referenced in function _main
1>main.obj : error LNK2019: unresolved external symbol"public: void __thiscall DynIntStack<char>::pop(char &)" (?pop@?$DynIntStack@D@@QAEXAAD@Z) referenced in function _main
1>main.obj : error LNK2019: unresolved external symbol"public: void __thiscall DynIntStack<char>::push(char)" (?push@?$DynIntStack@D@@QAEXD@Z) referenced in function _main

DytStang.h

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45

DYNTITSTACK.CPP

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125

/****************************************************************************
DynIntStack class.

Chad Peppers

This class creates a object for stacking nodes

In addition, there should be member functions to perform the following
operations:
- Push to the stack
- Pop to the stack
- Function to check if empty

****************************************************************************/

#include <iostream>
#include"DynIntStack.h"
using namespace std;

/*************************************************************************
Basic class constructor.

Input Parameters: Information to build the stack

Return Type: void

*************************************************************************/

template<class T>
DynIntStack<T>::~DynIntStack()
{
StackNode *nodePtr, *nextNode;

// Position nodePtr at the top of the stack.
nodePtr = top;

// Traverse the list deleting each node.
while (nodePtr != NULL)
{
nextNode = nodePtr->next;
delete nodePtr;
nodePtr = nextNode;
}
}

/*************************************************************************
Function to push an item in the stack

Input Parameters: T

Return Type: void

*************************************************************************/

template<class T>
void DynIntStack<T>::push(T num)
{
StackNode *newNode; // Pointer to a new node

// Allocate a new node and store num there.
newNode = new StackNode;
newNode->value = num;

// If there are no nodes in the list
// make newNode the first node.
if (isEmpty())
{
top = newNode;
newNode->next = NULL;
}
else // Otherwise, insert NewNode before top.
{
newNode->next = top;
top = newNode;
}
}

/*************************************************************************
Function to pop an item in the stack

Input Parameters: T

Return Type: void

*************************************************************************/
template<class T>
void DynIntStack<T>::pop(T &num)
{
StackNode *temp; // Temporary pointer

// First make sure the stack isn't empty.
if (isEmpty())
{
cout <<"The stack is empty.
";
}
else // pop value off top of stack
{
num = top->value;
temp = top->next;
delete top;
top = temp;
}
}

/*************************************************************************
Basic class deconstructor.

Input Parameters: None

Return Type: void

*************************************************************************/
template<class T>
bool DynIntStack<T>::isEmpty()
{
bool status;

if (!top)
status = true;
else
status = false;

return status;
}

主CPP

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

#include <iostream>
#include"DynIntStack.h"
using namespace std;

int main(){

int value = 0;
char value2;
//DynIntStack<int> stack;
DynIntStack<char> stack1;

cout <<"Pushing 1
";
stack1.push('T');
stack1.pop(value2);
cout << value2;

system("pause");
return 0;
}

您需要将.cpp文件中的所有模板实现放在头文件中，或者放在头文件包含的文件中。不要试图编译实现文件。有些系统试图编译后缀为.cpp的文件。编译器需要查看代码才能实例化模板。