c++ - C++控制台未显示菜单

如果用户选择1或2，则功能无法运行。有什么建议么？

#include <iostream>
using namespace std;

void getTitle();
void getIsbn();

int main()
{
    int choice = 0;      // Stores user's menu choice

    do
    {
        // Display menu
        cout << "             Main Menu\n\n\n";

        // Display menu items
        cout << "   1. Choose 1 to enter Title.\n";
        cout << "   2. Choose 2 to enter ISBN.\n";
        cout << "   3. Choose 3 to exit.\n";

        // Display prompt and get user's choice
        cout << "   Enter your choice: ";
        cin  >> choice;

        // Validate user's entry
        while (choice < 1 || choice > 3)
        {
            cout << "\n   Please enter a number in the range 1 - 3. ";
            cin  >> choice;
        }

        switch (choice)
        {
        case 1:
            getTitle();
            break;
        case 2:
            getIsbn();
            break;
        }
    } while (choice != 3);

    return 0;
}

void getTitle()
{
    string title;
    cout << "\nEnter a title: ";
    getline(cin, title);
    cout << "\nTitle is " << title << "\n\n\n";
}

void getIsbn()
{
    string isbn;
    cout << "\nEnter an ISBN: ";
    getline(cin, isbn);
    cout << "\nISBN is " << isbn << "\n\n\n";
}

最佳答案

这些函数当然应该被调用。但是，将发生的是，当您按“ Enter”键键入数字时生成的换行符将由getline()返回，并且该函数将返回而不会真正提示您。您需要清除该换行符。您可以使用ignore()来执行此操作：读入cin.ignore();后立即添加choice以忽略一个字符。