While Loop Won't loop C++

问题

I can't seem to figure out why this while loop stopped looping. It was doing fine before I moved some code around. Now I got something else working and it just doesn't loop. I've also tried making quit a bool set to true and tried to have it loop while it was true until the user hit 4 to exit in which case it would turn it to false but that didn't work. I also tried adding a while loop to the function of showMenu but that also didn't work. I know it must be something simple I just can't catch it. gggrrrr.

#include "stdafx.h"
#include <iostream>
#include <iomanip> 

using namespace std; 

enum transType { SETUP=1, DEPOSITE, WITHDRAW, EXIT};

int showMenu(double balance);
double transaction(double amount, double balance, transType trans);

int menuSwitch; 
int quit=0; 

int _tmain(int argc, _TCHAR* argv[]){

    int amount=0,balance=0; 
    while(quit!=4){

    showMenu(balance);
    switch (menuSwitch){
        case DEPOSITE:
            cout<<"Enter the amount of deposit: ";
            cin>>amount;
            cout<<"Your current balance is: "<<transaction(amount,balance,DEPOSITE)<<endl<<endl;
            break;
        case WITHDRAW:
            cout<<"Enter the amount of withdraw: ";
            cin>>amount; 
            if(amount>balance){
                cout<<"*** Insufficient funds."<<"Your current balance is: "<<transaction(amount,balance,WITHDRAW)<<endl<<endl; 
            }
            else cout<<"Your current balance is: "<<transaction(amount,balance,WITHDRAW)<<endl<<endl;
            break;
        case EXIT:
            cout<<"Have a Nice Day."<<endl;
            quit=4;
            break;

    }

    return 0;
}
}
int showMenu(double balance){
    // while(quit==true){
    cout<<"Your Online Checking Account System"<<endl;
    cout<<"-------------------------------------------"<<endl; 
    cout<<"Select an option:"<<endl<<endl; 
    cout<<"  1. Set up the account."<<endl; 
    cout<<"  2. Deposit Funds into your Account."<<endl; 
    cout<<"  3. Withdraw Funds out of your Account."<<endl; 
    cout<<"  4. Exit"<<endl; 
    cout<<endl<<">>";
    cin>>menuSwitch;
    switch (menuSwitch){
        case SETUP:
            cout<<"Enter the balance: ";
            cin>>balance;
            cout<<endl<<"Your current balance is: "<<balance<<endl<<endl;
            break; 
    }

    return balance;
    // }
}
double transaction(double amount, double balance, transType trans){
    double withdraw = balance-amount;
    double deposite = balance+amount;
    if(trans=DEPOSITE){
        return deposite; 
    }
    else
        return withdraw; 





}
    //return balance; 

回答1:

You return 0 within the switch brackets, ie inside the while loop. Change it so that you return 0 outside of the while loop.

来源：https://stackoverflow.com/questions/15038584/while-loop-wont-loop-c