Why wont this work ? readin in file names? c++?

Question

vector<string> read_all_files( vector<string> filenames )

{

vector<string> result;

string line;

for (vector<string>::iterator filename = filenames.begin();

filename != filenames.end();

filename++

) {

ifstream file( *filename ); ////////////////////////// THIS LINE IS PROBLEMATIC

if (!file) continue;

while (getline( file, line )) result.push_back( line );

file.close();

}

return result;

}

Answer 1

its been a while but i think you have to open the file when you use ifstream before you read it.

ifstream file;

file.open(*filename);

Answer 2

The ifstream constructor takes a C-style string, i.e. char*, not std::string.  You can get a C-style string from std::string by the c_str() function.

(*filename).c_str()

Automatic conversion from std::string to char* was intentionally not included because automatic conversions can happen in unexpected places.  This way the conversion occurs only when the programmer explicitly asks for it.