程序返回到第一個功能，而不是下一個功能

Question

好吧，我正在完成一個書店的程序。但是，運行我的代碼時，它的工作原理是 ，但不正確。首先顯示用戶從4個選項中選擇的主菜單功能，輸入數字並顯示下一個選擇的功能。當試圖從第二個功能中選擇 時，程序返回到第一個功能並重新開始。例如， mainmenu（） - > invmenu（）（從invmenu（）） - >中選擇addBook（）函數，但取而代之，它返回到mainmenu（），而不是
。我不知道爲什麼會發生這種情況。我嘗試了每個部分分開 ，他們工作得很好。

This is my code so far 
//The main menu displays a window where the user can 
//choose which one module to run or exit the program 
//Luis Fierro 
//11-8-2014 

#include "mainmenu.h" 


#include <iostream> 
#include <iomanip> 
#include <string> 
#include <cstdio> 
#include <cstdlib> 

using namespace std; 

//prototypes 
void mMenu(); 
void cashier(); 
void invmenu(); 
void report(); 
void bookInfo(); 

//inventory function prototypes 
void lookUpBook(); 
void addBook(); 
void editBook(); 
void deleteBook(); 



int main() 
{ 
mMenu(); 
} 

void mMenu() 
{ 

    int choice; 

    do{ 
     //display the menu and get a choice 
     cout << "\t\t\tSerendipity Booksellers\n" << endl; 
     cout << "\t\t\t\tMain Menu\n\n" << endl; 
     cout << "1. Cashier Module\n" << endl; 
     cout << "2. Inventory Database Module\n" << endl; 
     cout << "3. Report Module\n" << endl; 
     cout << "4. Exit \n\n" << endl; 

     cout << "Enter Your Choice: \n" << endl; 
     cin >> choice; 

     //make sure numbers are not out of the range 
     while (choice <= 0 || choice > 4) 
     { 
      cout << "Please enter a number in the range 1-4 " << endl; 

      cout << "Enter Your Choice: \n" << endl; 
      cin >> choice; 
     } 

     //respond to the user's selection 
     switch (choice){ 
     case 1: cashier(); 
      break; 
     case 2: invmenu(); 
      break; 
     case 3: report(); 
      break; 
     case 4: 
      cout << "Bye, bye!!!" << endl; 
      break; 
     } 

    } while (choice != 4); 

    system("Pause"); 


} 
//function cashier 
void cashier() 
{ 
//initialize variables 
    int option; 
    string date; 
    int bQuantity; 
    string isbn; 
    string bTitle; 
    float bPrice; 
    double total = 0.0; 
    double tax = 0; 
    double subtotal = 0.0; 

    //constant 
    const double YES_OPTION = 1, 
     NO_OPTION = 2; 

    //ask the user 
    cout << "What is the date(MM/DD/YY): " << endl; 
    cin >> date; 
    cout << "\n" << endl; 
    cout << "Number of books purchased: " << endl; 
    cin >> bQuantity; 
    cout << "\n" << endl; 
    cout << "ISBN number: " << endl; 
    cin >> isbn; 
    cout << "\n" << endl; 
    Court << "Title of book: " << end; 
    cin >> bTitle; 
    cout << "\n" << endl; 
    cout << "Cost of book: " << endl; 
    cin >> bPrice; 
    cout << " \n\n" << endl; 

    //display information to the user 
    cout << "Serendipity Booksellers\n" << endl; 
    cout << "\tCashier Module\n\n" << endl; 
    cout << "Date: " << date << " \n" << endl; 
    cout << "Quantity of Book " << bQuantity << "\n" << endl; 
    cout << "ISBN " << isbn << " \n" << endl; 
    cout << "Title: " << bTitle << "\n" << endl; 
    cout << "Price: $" << bPrice << "\n\n\n" << endl; 

    //calculations 
    subtotal = (bQuantity*bPrice); 

    tax = (bQuantity*bPrice)*0.06; 

    total = subtotal + tax; 

    //display final window with all the info 
    cout << "Serendipity Book Sellers\n\n " << endl; 
    cout << "Date: " << date << endl; 
    cout << "\nQty  ISBN  Title  Price  Total\n\n" << endl; 
    cout << "________________________________________________________\n\n\n" << endl; 
    cout << " " << bQuantity << " \t\t" << isbn << "\t" << bTitle << "\t\t$" << bPrice <<  "\t\t$" << subtotal << endl; 
    cout << "  \n\n\tSubtotal: " << "\t\t\t\t\t\t$" << subtotal << endl; 
    cout << "   \n\tTax: " << "\t\t\t\t\t\t\t$" << tax << endl; 
    cout << "   \n\tTotal: " << "\t\t\t\t\t\t\t$" << total << endl; 

    cout << "\n\nThank You for Shopping at Serendipity!\n\n" << endl; 


    //ask user if needs another transaction 
    cout << "\t\tAnother transaction?" << endl; 
    cout << "\t\t1. Yes" << endl; 
    cout << "\t\t2. No\n" << endl; 
    cin >> option; 

    if (option == YES_OPTION) 
    { 
     cashier(); 
    } 
    else if (option == NO_OPTION) 
    { 
     cout << "\nPlease come again!!" << endl; 
    } 


    cin.get(); 

    } 
//second menu 
void invmenu() 

{ 
    //initialize variable 
    int choice1; 

    do {//display the menu 
     cout << "\t\t\tSerendipity Booksellers\n" << endl; 

     cout << "\t\t\tInventory Database\n" << endl; 

     cout << "\n\t\t\t1. Look Up a Book" << endl; 

     cout << "\n\t\t\t2. Add a Book" << endl; 

     cout << "\n\t\t\t3. Edit a Book's Record" << endl; 

     cout << "\n\t\t\t4. Delete a Book" << endl; 

     cout << "\n\t\t\t5. Return to the main menu" << endl; 

     cout << "\n\t\t\tEnter Your Choice: \n " << endl; 

     cout << "Enter Your Choice: \n" << endl; 
     cin >> choice1; 

     //make sure numbers are not out of range 
     while (choice1 <= 0 || choice1 > 5) 
     { 
      cout << "Please enter a number in the range 1-5 " << endl; 

      cout << "Enter Your Choice: \n" << endl; 
      cin >> choice1; 
     } 


     //Respond to the user's selection 
     switch (choice1){ 
     case 1: lookUpBook(); 
      break; 
     case 2: addBook(); 
      break; 
     case 3: editBook(); 
      break; 
     case 4: deleteBook(); 
      break; 
     case 5: mMenu(); 
      break; 
     } 

    } while (choice1 = !5); 
    cin.get(); 


} 
//last functions for the invmenu 
void lookUpBook() 
{ 

    cout << "You selected look up a book" << endl; 
} 

void addBook() 
{ 

    cout << "You selected add a book" << endl; 
} 

void editBook() 
{ 
    cout << "You selected edit a book" << endl; 
} 

void deleteBook() 
{ 
    cout << "You selected delete a book" << endl; 
} 

Answer 1

由於SleuthEye指出的那樣，你的循環條件choice1 = !5導致invmenu結束其循環無論用戶做什麼。我建議你打算這樣做：

choice1 != 5