Header file help

[BlekksPoncho]

Hi I have been refreshing myself on simple C stuff, but something isn't working; Say I am creating a little program that outputs Hello as a string.

I include string in stdafx.h (which VC++2005 creates to manage all the headers).

Then i decide to make it a function that outputs hello above the main():

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void helloOutput(string string1)
{
cout<<string1;
}

Then I decide to put this function in its own header file called, MainHeaders.

I then reference this header file in stdafx.h but when I compile it says that "string is an undelcared identifier" so I am guessing that means that I have not included <string>. But it will be the main file that uses this function, and the main file has stdafx included.

What is wrong?

Thanks.

[Sauce]

last time i checked, there was no 'string' data type (or at least for me, for some reason it doesnt work D: ) so instead, use an array of char variables:

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char[] string;

or is it

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char string[];

I cant remember, havent done any coding in ages.[/code]

[Forceflow]

In C: no classes, thus no string. Chars are the way to go.
In C++: String should be included by default. Check that auto-generated file for the correct includes.

#include <string>

[BlekksPoncho]

Well here is my file structure:

main.cpp includes:

stdafx.h
-------------------

stdafx.h includes:

<string>
<iostream>
"mainquiz" (my header file with all the functions)
-------------------

Strings work in main.cpp as they are included through stdafx.h but when compiling, I get an error saying that mainquiz.h has the undeclared identifier "string".
But the main.cpp file is the one using the functions so why does it matter, cos they will have <string> included anyway?
I then included <string> in the mainquiz.h header, but I got the same errors.

Anyone know what is wrong?

Thanks.

[Sauce]

show us the files?

[BlekksPoncho]

All the files are here:

http://www.mpagbyorksregion.co.uk/tomsmith/c++/

Thanks.

[ChopperDave]

The string class is part of the std namespace. Unless you declare you're using that namespace somewhere in your code, you'll have to explicitly access the string class through the namespace by doing std::string.

To use the namespace (and thus eliminate the need for going through it), you can say:

using namespace std;

Near the top of your cpp file, after your #includes.

[BlekksPoncho]

If you look at MethodTesr.cpp I do have "using namespace std" at the start of that file, but do I need to add it anywhere else?

Such as in the MainQuiz.h header file which has all the functions in, that contain strings that MethodTesr.cpp uses.

[zombie@computer]

if you use string in the header file, you must do a using namespace std in the header file as well offcourse

[BlekksPoncho]

Yeah ok, I am using it in the header file now but I am getting weird errors about chars and the MethodTesr.obj file. I am not at my computer right now but on my Archos 604 Wifi.