Question

我正在尝试创建用户输入名称的文本文件。它应该只创建文本文件，然后将其关闭，然后如果成功创建，则通过终端提供反馈。如果我硬编码文件名，我能够弄清楚如何创建文件，但现在我正在尝试使用用户输入我无法创建文件。现在它甚至不让我输入任何东西，它只是在我调用函数时结束。谢谢您的帮助。

编辑：我不确定是不是因为我的getline电话只是得到一个空行然后结束或为什么它不会让我cin任何东西。

EEDIT：这是我的完整代码，我想我认为不起作用的部分是，所以希望有人可以告诉我为什么我的代码在我为我的开关案例选择1之后才结束。显然我的代码并不完整，但这就是我所拥有的一切。

#include <iostream>
#include <fstream>
#include <stdio.h>

using namespace std;

void createDB() {
    ofstream db;
    string filename;
    cout << "Enter the name of the database you want to create: \n";
    getline (cin, filename);

    db.open(filename.c_str());
    if(!db) { // checking if the file could be opened
        cout << "\nCould not create database\n";
    }// add more checks to make sure file doesn't have same name
    else {
        cout << "\nYour database " << filename << " was created successfully\n";
    }

    db.close();

}

void openDB() { // just opens hard coded file for now
    // need to add check to see if one is already open
    cout << "Enter the name of the database you want to open: ";
    string line;

    //ifstream file (
}

void closeDB() {

}

void display() {

}

void update() {

}

void create() {

}

void add() {

}

void del() {

}

int menu() {
    cout << "Enter the number of the operation you wish to perform (1-9)\n"
    << "1. Create new database\n"
    << "2. Open database\n"
    << "3. Close database\n"
    << "4. Display record\n"
    << "5. Update record\n"
    << "6. Create report\n"
    << "7. Add a record\n"
    << "8. Delete a record\n"
    << "9. Quit\n";

    int sel = 0;
    cin >> sel;

    switch (sel) {
        case 1: createDB();
            //menu(); // after creating file go back to list of options
            break;

        case 2: openDB();
            break;

        case 3: closeDB();
            break;

        case 4: display();
            break;

        case 5: update();
            break;

        case 6: create();
            break;

        case 7: add();
            break;

        case 8: del();
            break;

        case 9: return 0;
            break;

        default: cout << "Please try again and enter a valid number\n\n";
            menu();
            break;
    }
    return true; // to avoid error saying control may reach end of non-void function
}


int main() {
    menu();

    return 0;
}

Answer 1

您发布的代码实际上是有效的，但由于您之前的代码，它似乎getline skips input。因此，如果您发布了其余代码，那将非常有用。

因此，因为您在cin之前使用getline，所以应在std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');之后添加cin >> sel;。

所以你的菜单功能是

int menu() {
cout << "Enter the number of the operation you wish to perform (1-9)\n"
    << "1. Create new database\n"
    << "2. Open database\n"
    << "3. Close database\n"
    << "4. Display record\n"
    << "5. Update record\n"
    << "6. Create report\n"
    << "7. Add a record\n"
    << "8. Delete a record\n"
    << "9. Quit\n";

int sel = 0;
cin >> sel;
std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');

switch (sel) {
case 1: createDB();
    //menu(); // after creating file go back to list of options
    break;

case 2: openDB();
    break;

case 3: closeDB();
    break;

case 4: display();
    break;

case 5: update();
    break;

case 6: create();
    break;

case 7: add();
    break;

case 8: del();
    break;

case 9: return 0;
    break;

default: cout << "Please try again and enter a valid number\n\n";
    menu();
    break;
}
return true; // to avoid error saying control may reach end of non-void function
}

如何允许用户命名创建的文本文件c ++

1 个答案: