a class with a ifstream member

Hano · 04-23-2002, 10:16 PM

Hi,

im having problems because i want to do a class with a ifstream member variable, but given the sintax for calling a ifstream:

ifstream blaj (filename, size);

then im not sure about what im trying to do

class file_manager {
ifstream file;
//methods go here
....
};
it just compile fine (on icc) but then i try to open it

file_manager test;
ifstream test.file (flahh...);

and it just doesn't seem to like it,
is there any other way of doing this?

the reason i want a ifstream on a class is because i want to open arrays of files, so it looks like this:

file_manager filearray[50];
for( i=0 ; i < 50 ; i++) {
filearray[i].getline(buffer,256);
cout << "reading from file "<<i<<" i found "<<buffer<<endl;
};

any ideas how to do this?

Hano

Mik · 04-24-2002, 06:33 AM

I think you are mixing up a few things there. I'm not totally clear on what you want to do. But the best way is to either make a class that handles everything for you or just make an array of ifstreams without using a class.

To do it with a class you could do something like this:

Code:

class file_manager
{
public:
  file_manager();
  ~file_manager();

  bool open(char* name);
  char* getline();
  bool close();

private:
  ifstream m_file;
};

Ofcourse you'll have to implement all the contents of those functions yourself but most of them will be just simply calling the members of ifstream.

To do it without a class you could do something like this:

Code:

ifstream filearray[50];
for( i=0 ; i < 50 ; i++)
{
  filearray[i].open(filename[i]);
  filearray[i].getline(buffer,256);
  cout << "reading from file " << i
          << " data: " << buffer << endl;
}

Hano · 04-24-2002, 11:01 AM

Thanx Mik!

that was just what i was trying to do, but the key was the open() member, that it doesnt appear documented nowhere...
maybe because nobody assumes you need not to open on declaration

Hano