To use the things described here, #include the <fstream> library.
ifstream in(path);
|
ifstream is a type. This statement creates an
ifstream object called in that reads from the file
described by string path.
See in.fail() below. |
in >> x;
| Do with an open ffstream object all of the same things that you can do with cin. |
in.fail()
Expression in.fail() is true if the
most recent attempt to read from file in
could not be done, or if file in could
not be opened. You should be sure to test
this after opening a file, since the file
that you are trying to open might not exist
or might not be readable. For example,
write
ifstream in("data.txt");
if(in.fail())
{
(what to do if the file could not be opened)
}
|
in.close()
| Use this to close file in when you are done reading from it. |