将向量的字符串定义为全局 [英] Defining the Vectors for strings as global

问题描述

我在x.cpp文件中将容器定义为

Hi,
I am defining a container in a x.cpp file as

vector<string> somevariable;

我正在尝试在另一个y.cpp文件中使用它.我在y.cpp文件中将向量声明为extern，如

I am trying to use it in another y.cpp file. I declare the vector as extern in y.cpp file like

extern vector<string> somevariable;

但是，当我编译程序时，出现如下错误:
1)somevariable:找不到标识符；甚至具有依赖于参数的查找
2)错误C2143:语法错误:在``<''
之前缺少``;''
我在文件中包括了<string>, <vector>，还包括了using namespace std;

我缺少什么?

But when I compile the program I get the errors like:
1) somevariable : identifier not found; even with argument dependent lookup
2) error C2143: syntax error : missing '';'' before ''<''

I have included <string>, <vector> in my files and also using namespace std;

what am I missing?

推荐答案

您是否在项目中包含了x.cpp文件?
您是否在y.cpp和x.cpp源文件中都包含了必需的标头?
以下测试:
文件b.cpp

Did you include x.cpp file in your project?
Did you include the required headers in both y.cpp and x.cpp source files?
The following test:
file b.cpp

#include <vector>
#include <string>

using namespace std;

vector <string> v;

文件main.cpp

file main.cpp

#include <vector>
#include <string>
#include <iostream>

using namespace std;

extern vector<string> v;
int main()
{
  v.push_back(string("hi"));
  cout << v[0] << endl;
} 

可以编译(运行).
:)

compiles (and runs) fine.
:)

我认为您需要声明它extern并在x.cpp中对其进行初始化.请参阅 MSDN参考 [

I think you need to declare it extern and initialise it in x.cpp. See the MSDN reference[^] for further information.

I stand corrected; Signor Pallini has the answer.

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