Error C2079 Ofstream

Development > C++ Standards, Extensions, and Interop Question 0 Sign in to vote Hi, all. I can't figure out why this simple console program does not compile. All I want to do is create a fstream. The code is below:#include using namespace std;int _tmain(int argc, _TCHAR* argv[]) {    fstream file;    return 0;}And the error I get is:1>d:\development\visual studio projects\streamtest\streamtest\streamtest.cpp(9) : error C2079: 'file' uses undefined class 'std::basic_fstream<_Elem,_Traits>'1>        with1>        [1>            _Elem=char,1>            _Traits=std::char_traits1>        ]I get the same error any other type of stream. Tuesday, November 28, 2006 10:11 AM Reply | Quote Answers 1 Sign in to vote try this#include #include using namespace std;int _tmain(int argc, _TCHAR* argv[]) { ifstream infile; infile.open ("test.txt", ifstream::in); while (infile.good()) cout << (char) infile.get(); infile.close(); return 0;} Tuesday, November 28, 2006 10:25 AM Reply | Quote 0 Sign in to vote The fstream class is defined in the fstream header. Try adding a #include . Tuesday, November 28, 2006 10:13 AM Reply | Quote Moderator 0 Sign in to vote Next time you have this kind of problems please check with MSDN to see what header you have to include for a class or function. Tuesday, November 28, 2006 1:03 PM Reply | Quote All replies 0 Sign in to vote The fstream class is defined in the fstream header. Try adding a #include . Tuesday, November 28, 2006 10:13 AM Reply | Quote Moderator 1 Sign in to vote try this#include #include using namespace std;int _tmain(int argc, _TCHAR* argv[]) { ifstream infile; infile.open ("test.txt", ifstream::in); while (infile.good()) cout << (char) infile.get(); infile.close(); return 0;} Tuesday, November 28, 2006 10:25 AM Reply | Quote 0 Sign in to vote Next time you have this kind of problems please check with MSDN to see what header you have to incl

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Forum Visual C++ & C++ Programming Visual C++ Programming ifstream "uses undefined class" If this is your http://forums.codeguru.com/showthread.php?296051-ifstream-quot-uses-undefined-class-quot first visit, be sure to check out the FAQ by clicking the link above. You may have to register or Login before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. Results 1 to 3 of 3 Thread: ifstream "uses undefined error c2079 class" Tweet Thread Tools Show Printable Version Email this Page… Subscribe to this Thread… Display Linear Mode Switch to Hybrid Mode Switch to Threaded Mode May 25th, 2004,12:48 AM #1 code_addict View Profile View Forum Posts Junior Member Join Date May 2004 Posts 2 ifstream "uses undefined class" Hi everyone, I am new to C++, trying to error c2079 ofstream learn it on my own. I am using VC++ 6.0 and I'm trying to create a VERY simple program that replaces string in specified text files. I'm trying to use ifstream for this purpose, but when I try to create an ifstream object like this #include using namespace std; int main(int argc, char *argv) { ifstream inFile; return 0; } ...and try to compile, VC++ spits out the message error C2079: 'inFile' uses undefined class 'basic_ifstream >' Error executing cl.exe. I am using standard installed libraries - nothing special. Any clues? thanks for any help Reply With Quote May 25th, 2004,01:18 AM #2 Paul McKenzie View Profile View Forum Posts Elite Member Power Poster Join Date Apr 1999 Posts 27,449 Wrong header: Code: #include using namespace std; int main(int argc, char *argv) { ifstream inFile; return 0; } Regards, Paul McKenzie Reply With Quote May 26th, 2004,12:49 AM #3 code_addict View Profile View Forum Posts Junior Member Join Date May 2004 Posts 2 Thanks, Mr. McKenzie Reply W