Extraction before Getline

Extraction Before Getline

The getline() function and the extraction operator >> handle a trailing newline differently, which can lead to a problem.

• The getline() function reads a line of text from a buffer, discarding the ending newline character.
• The extraction operator >> skips whitespace, then reads the next item such as an integer or string which is said to end at the next whitespace, leaving that ending whitespace character in the buffer (an exception being for reading a single character).

The problem is that code like cin >> myInt; and getline(cin, nextLine); may not behave as expected if the integer is ended with a newline. The getline() function will read that single remaining newline character, returning an empty string, rather than proceeding to the next line. . A simple solution is to not mix the two approaches to reading an input buffer, either only using extraction, or only using getline(). . If one must mix the two approaches, then after an extraction operation, the trailing newline should be discarded from the buffer before calling the getline(), by inserting some statement in between. One possible solution inserts cin.ignore(), which discards the next character in the input buffer. Another possible approach inserts another getline() call, ignoring its blank string.