C ++：Switch语句实现

Question

I'm attempting to use a switch statement in the main part of my program, here is what I have...

main()
int userOption;
while (userOption=!0)
{


cout<<"BUSINESS MANAGEMENT system <16102868>"<<endl;
cout<<"-------------------------------------"<<endl;
cout<<"EMPLOYEE OPTIONS"<<endl;
cout<<"1. Add Employee"<<endl;
cout<<"2. Edit Employee"<<endl;
cout<<"3. Layoff Employee"<<endl;
cout<<"4. View Employee List"<<endl;
cout<<"----------------------------------"<<endl;
cout<<"SCHEDULING OPTIONS"<<endl;
cout<<"5. Update Schedule"<<endl;
cout<<"6. Cancel Schedule"<<endl;
cout<<"7. View Schedule"<<endl;
cout<<"8. Export Schedule to CSV"<<endl;
cout<<"9. Export Schedule to HTML"<<endl;
cout<<"---------------------------------"<<endl;
cout<<"0. Quit"<<endl;
cout<<"----------------------------------"<<endl;
cout<<"Please enter an option:"
cin>>userOption
switch (userOption)
{
case 1:
    AddEmployee()
        break;
case 2:
    EditEmployee()
        break;
case 3:
    LayoffEmployee()
        break;
case 4:
    DisplayEmployeeList()
        break;
case 5:
    AddSchedule()
        break;
case 6:
    CancelSchedule()
        break;
case 7:
    DisplaySchedule()
        break;
case 8:
    ExportScheduleCSV()
        break;
case 9:
    ExportScheduleHTML()
        break;
default:
    cout<<"Enter a number between 1 and 9:"<<endl;
}

I can't quite figure out where I'm going wrong here. Here's the code that has most of the above functions that I'm calling in it...

class EmployeeHandler
{
  public:
    void AddEmployee()
    {
      std::string firstName;
      std::string lastName;
      float payRate;

      std::cout<<"NEW EMPLOYEE"<<std::endl;
      std::cout<<"First Name:"<<std::endl;
      std::cin>>firstName;
      std::cout<<"Last Name:"<<std::endl;
      std::cin>>lastName;
      std::cout<<"Pay Rate:"<<std::endl;
      std::cin>>payRate;
      employees_.push_back( Employee( firstName,lastName,payRate ) );
      std::cout<<"**Employee m_employeeCount added"<<std::endl;
    }

    void EditEmployee()
    {
      std::string newFirst;
      std::string newLast;
      float newPay;
      std::cout<<"Which employee would you like to edit"<<std::endl;
      int indexEdit = GetSelection();
      Employee& employee = employees_[indexEdit];
      std::cout << employee << std::endl;
      std::cout<<"Employee new first name:"<<std::endl;
      std::cin>>newFirst;
      std::cout<<"Employee new last name:"<<std::endl;
      std::cin>>newLast;
      std::cout<<"Employee new pay rate:"<<std::endl;
      std::cin>>newPay;
      employee = Employee( newFirst, newLast, newPay );
      std::cout<<"** Employee index updated"<<std::endl;
    }

    void LayoffEmployee()
    {
      int index = GetSelection();
      if( employees_[index].GetIsActive() )
      {
        std::cout << "Laying off employee:\n" << employees_[index] << std::endl;
        employees_[index].LayOff();
      }
      else
      {
        std::cerr << "Already layed off employee:" << employees_[index] << std::endl;
      }
    }

    void DisplayEmployeeList()
    {
      std::copy( employees_.begin(), employees_.end(), std::ostream_iterator<Employee>( std::cout, "\n" ) );
    }

    int GetSelection()
    {
        std::size_t indexNumber;
        std::cout << "Select an employee from the list below by specifying its number:" << std::endl;
        DisplayEmployeeList();

        do{
          while( !std::cin >> indexNumber )
          {
            std::cerr << "Select a number..." << std::endl;
          }
          if( indexNumber >= employees_.size() )
          {
            std::cerr << "Select a number within range of list below:" << std::endl;
            DisplayEmployeeList();
          }
        }
        while( indexNumber >= employees_.size() );
        return indexNumber;
    }

    Employee& operator[]( std::size_t index )
    {
      return employees_[index];
    }

    const Employee& operator[]( std::size_t index ) const
    {
      return employees_[index];
    }

    std::size_t EmployeeCount() const
    {
      return employees_.size();
    }

  private:
    std::vector<Employee> employees_;
};

Answer 1

Your problem is that you are calling members (functions) of a class, and you do not have an object of that class.

Change your code like this:

main()
int userOption;

EmployeeHandler e;
// ....

switch (userOption)
{
case 1:
    e.AddEmployee();
    break;
 //...

Answer 2

There seem to be a lots of errors but maybe they are just typos (of course you should say what your error is, 'it doesn't work' is never good enough). But one error is this

int userOption;
while (userOption!=0)
{

    ...

    cout<<"Please enter an option:";
    cin>>userOption;
    switch (userOption)
    {

See the problem? Your while loop tests the value of userOption before you have given in a value.

Simple fix is to change your while loop into a do ... while loop.

int userOption;
do
{
    ...

    cout<<"Please enter an option:";
    cin>>userOption;
    switch (userOption)
    {
        ...
    }
}
while (userOption != 0);