ifstream::open() function using a string as the parameter

c++ string fstream ifstream
SemicolonExpected picture SemicolonExpected · Mar 2, 2013 · Viewed 12.2k times · Source

I'm trying to make a program that asks for the file that they user would like to read from, and when I try to myfile.open(fileName) I get the error: "no matching function for call to std::basic_ifstream<char, std::char_traits<char> >::open(std::string&)'" at that line.

string filename;
cout<<"Enter name of file: ";
cin>>filename;
ifstream myFile;
myFile.open(filename); //where the error occurs.
myFile.close();

Answer

hmatar picture hmatar · Mar 2, 2013

In the previous version of C++ (C++03), open() takes only a const char * for the first parameter, instead of std::string. The correct way of calling it would then be:

myFile.open(filename.c_str());

In current C++ (C++11) that code is fine, though, so see if you can tell your compiler to enable support for it.

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