c++ - 处理空格字符作为输入

Question

#include <iostream>
using namespace std;

int main() {
    int x;
    char y;
    cin >> x;
    while(!cin)
    {
        cout << "Error" << endl;
        cout << "Enter x and y again => ";
        cin.clear();
        cin.ignore(256,'\n');
        cin >> x;
    }
    cin >> y;
    while (!(!isblank(y) && isalpha(y)))
    {
        cout << "You have entered wrong values try again!" << endl;
        cout << "Enter x and y again => ";
        cin >> x >> y;
    }
    return 0;
}

如果输入的输入是 1 a，我会尝试处理。 x 应该是一个数字 y 也应该是字母字符。它应该再次要求输入值 x 和 y。然而，事实并非如此。它应该接受 1a。如何克服这个问题？

Answer 1

我会一次读取一行到缓冲区中，然后使用 stringstream 从该缓冲区中读取。这是对我有用的:

int x;
char y;
bool readin_successful = false;
while (cin) {
    cout << "Please enter x and y => ";
    char z;
    string buffer;
    getline(cin, buffer);
    stringstream bin(buffer);
    bin >> x >> y;
    bool const first_ok = (isalpha(y) and bin.good());
    bin >> z;
    if (first_ok and not bin.good()) {
        readin_successful = true;
        break;
    }
    cout << "You have entered wrong values try again!" << endl;
}
cout << "Read: " << x << " " << y << " " << readin_successful << endl;

它接受 0 x 和 0x，但不接受任何其他内容(忽略空格)。 Here是我测试过的示例输入。