我在catch块的异常类中调用了一个函数what(),但在what()中,函数正在打印垃圾值,因为它没有被分配任何值,而应该打印checkusername()函数抛出的值,但它没有这样做,请帮我。这是代码
#include <iostream>
#include <string>
#include <sstream>
#include <exception>
using namespace std;
class BadLengthException
{
public:
int n1;
BadLengthException(int n)
{
n1=n;
}
int what()
{
cout << n1;
}
};
bool checkUsername(string username) {
bool isValid = true;
int n = username.length();
if(n < 5) {
throw BadLengthException(n);
}
for(int i = 0; i < n-1; i++) {
if(username[i] == 'w' && username[i+1] == 'w') {
isValid = false;
}
}
return isValid;
}
int main() {
int T; cin >> T;
while(T--) {
string username;
cin >> username;
try {
bool isValid = checkUsername(username);
if(isValid) {
cout << "Valid" << 'n';
} else {
cout << "Invalid" << 'n';
}
} catch (BadLengthException e) {
cout << "Too short: " << e.what() << 'n';
}
}
return 0;
}
what
没有return
语句,因此导致了未定义的行为。我想你应该用return n1
而不是cout << n1
。