getline 使用

The iostreams by default do not throw exceptions when errors occur. If you want to enable them:

cout.execeptions( std::ios::badbit );

would enable exceptions if badbit is set.

To enable them all:

cout.execeptions( std::ios::badbit
| std::ios::eofbit
| std::ios::failbit );

The exceptions thrown are of type:

std::ios_base::failure

which is derived from std::exception.

In general though, it is easier not to use execptions, but to use constructs like:

while( std::getline( myStreamObj, line )){// process line}