无法计数作为输入的位数

Question

我的程序：从用户那里获得有关个人详细信息的输入信息，然后输出信息。

我的问题：程序无法计算作为电话号码字段输入的位数。它接受超过10位数字作为电话号码的输入。

我的目标：检查“电话号码”的输入并确保该号码是10位数字。

我的代码：

#include <iostream> 
#include <string> 
#include <limits> 

using namespace std; 

class Personal_Details 
{ 
public: 
    void setFirstName (string newFirstName); 
    void setLastName (string newLastName); 
    void setBirthdate (int newBirthday); 
    void setEMail  (string newEMail); 
    void setPhoneNumber (int newPhoneNumber); 
    void QUESTIONS(); 
    string getFirstName(); 
    string getLastName(); 
    string getEMail(); 
    int getPhoneNumber(); 
    int getBirthdate(); 

private: 
    string FirstName; 
    string LastName; 
    string EMail; 
    int PhoneNumber; 
    int Birthdate; 
}; 

void Personal_Details :: setFirstName (string newFirstName) 
{ 
    FirstName = newFirstName; 
} 

void Personal_Details :: setLastName (string newLastName) 
{ 
    LastName = newLastName; 
} 

void Personal_Details :: setBirthdate (int newBirthdate) 
{ 
    Birthdate = newBirthdate; 
} 

void Personal_Details :: setEMail (string newEMail) 
{ 
    EMail = newEMail; 
} 

void Personal_Details :: setPhoneNumber (int newPhoneNumber) 
{ 
    PhoneNumber = newPhoneNumber; 
} 

string Personal_Details :: getFirstName() 
{ 
    return FirstName; 
} 

string Personal_Details :: getLastName() 
{ 
    return LastName; 
} 

int Personal_Details :: getBirthdate() 
{ 
    return Birthdate; 
} 

string Personal_Details :: getEMail() 
{ 
    return EMail; 
} 

int Personal_Details :: getPhoneNumber() 
{ 
    if (PhoneNumber>12) 
    { 
     cout <<"INVALID. Program will now close."; 
    } 
    system ("PAUSE"); 

    return PhoneNumber; 
} 

void Personal_Details :: QUESTIONS() 
{ 
    cout << "A.) Enter the following details:-" << endl <<endl; 
    cout << "First Name: "; 
    getline (cin, FirstName); 
    cout << endl; 

    cout << "Last (Family) Name: "; 
    getline (cin, LastName); 
    cout << endl; 

    cout << "Birthdate: "; 
    cin >> Birthdate; 
    std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); 
    cout << endl; 

    cout << "Email Address: "; 
    getline (cin, EMail); 
    cout << endl; 

    cout << "Phone Number: "; 
    cin >> PhoneNumber; 
    cout << endl; 

    cout<< FirstName <<" "<< LastName << endl 
     <<"Birthdate: "<< Birthdate << endl 
     <<"Email ID: "<< EMail << endl 
     <<"Phone Number: "<< PhoneNumber << endl; 
} 

int main() 
{ 
    Personal_Details NewContact; 
    cout << "- Add New Contact Information -" << endl << endl; 
    cout << "Note: Please type in only intergers (numbers) for 'Birthdate' and 'Phone Number' field. Also, phone number should be less than/or equal to 10 digits." << endl; 
    cout << "Else, this program will terminate abruptly." << endl << endl; 
    NewContact.QUESTIONS(); 
    cout << endl << endl; 

    cout << "Press Any Key to Exit."; 
    cin.ignore(); 
    cin.get(); 

    return 0; 
} 

请您可以查看和检查为什么我不能输入一个真正的10位数字的电话号码？我是C++的新手，所以我无法找出解决方案。谢谢你的帮助！

Answer 1

您将电话号码存储为int，但整数范围是-2,147,483,648至2,147,483,647;在该范围外输入一个10位数字会导致溢出，并可能导致程序崩溃。

您可能希望以电话号码的形式读入字符串，检查每个字符的有效性，然后根据需要对其进行处理（例如：区号的变量，7位数的变量，拒绝超出范围输入并重新提示）。