问题
So, I read a string using cin.getline(str,10,'h') where as you can see I have used a custom delimiter 'h' and want to read a maximum of 9 characters. After doing this, I use cin>>n to read an integer into my int variable n.
#include <iostream>
using namespace std;
int main() {
int n;
char str[100];
cin.getline(str, 10, 'h');
cout<<str<<'-'<<endl;
cout<<"Enter a number:";
cin>>n;
cout<<n;
return 0;
}
Suppose I pass the following input
2 3 pl32
which is a '\n' followed by "2 3 pl32".
I expect getline to read the string "\n2 3 pl"
and then cin to read the integer 32. But that's isn't what happened.
The actual output showed that the cin read garbage value:
2 3 pl-
Enter a number:0
Edit: Ok, so I get it now. Getline set the failbit
, that's what caused the issue. Problem solved.
回答1:
The problem is that getline
has not found its delimiter, and has set the failbit flag in cin
. You must clear the flag to read again on the stream:
...
cin.getline(str, 10, 'h');
cin.clear(); # reset a possible error condition
cout<<str<<'-'<<endl;
cout<<"Enter a number:";
cin>>n;
...
来源:https://stackoverflow.com/questions/56474039/how-to-make-cin-work-after-using-getline