include string class on c++ and eclipse

Question

i have a c++ project on eclipse and i can to use the string class in main file, but when i add a new file to the project I can not use any class.

I add file how: New-> Source file and select Template: Defaul c++ template source.

This is error src/Common.cpp:8:17: error: ‘string’ was not declared in this scope

and in src/AC.cpp all ok

thanks very much

Thanks larsman my simple code is:

AC.cpp -> all ok

include <iostream>
using namespace std;

int main()
{
string j = !!!Hello World!!!;
cout << j << endl; // prints !!!Hello World!!!
return 0;
}

Common.cpp -> src/Common.cpp:8:17: error: ‘string’ was not declared in this scope

#include <string>
void PrintTrace(string message)
{
    string j = !!!Hello World!!!;
cout << j << endl; // prints !!!Hello World!!!
}

both files are the same project.

Thanks

score 4 · Accepted Answer · answered Jan 10 '12 at 16:04

4

#include <string>

You have to include this header in all modules that use std::string.

answered Jan 10 '12 at 16:04

Fred Foo

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thank now all ok, i add: using namespace std; but whith std::string no work – Jjreina Jan 10 '12 at 16:20

score 1 · Answer 2 · edited May 23 '17 at 11:48

1

In addition to adding the include directive #include <string> (as stated by larsmans) you must refer to it using its fully qualified name std::string.

If you want to use string only, add using std::string; to each .cpp source file where it is used (you could also add using namespace std; but this is not recommended).

edited May 23 '17 at 11:48

Community

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1

answered Jan 10 '12 at 16:14

hmjd

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include string class on c++ and eclipse

2 Answers2