C++实现简单通讯录
本文实例为大家分享了C++实现简单通讯录的具体代码,供大家参考,具体内容如下
说明:
1 程序中运用到两个类,一个是Person类,另一个是List类。前者存储用户信息,后者主要用于操作,如增删改查等。但由于本程序中没有涉及到太复杂的功能,用户信息可以由一个简单的结构体表示,但是为了以后拓展方便,和达到学习运算符重载的目的,还是使用了类。
2 List类中的Reflush()方法用户刷新文件内容,即每次修改了vector后要将最新内容写入到文件。因此增删改操作中都要调用该操作,这种方法在数据库开发中常用到,以小见大。
3 setout()方法设置字符左对齐,便于美观。另外std::cout.width(15)设置输出字符域宽度,只对下一次输出有效。
4 判断文本文件是否为空还有另一种方法,即string类中的empty()方法,但为了读取方便没有采用。
5 其实对于通讯录的操作只是在类内的vector容器中进行,只有最后刷新的时候同步到磁盘文件中。
6 一些函数中设置多个返回值有利于判断操作的情况。
Person.h 与cpp文件:
#ifndef PERSON_H_ #define PERSON_H_ #include <string> class Person { public: std::string name; std::string tel; public: Person(); ~Person(); int operator==(const Person& p);//重载==运算符,本程序中并没有用到 private: }; #endif // !PERSON_H_
#include "Person.h" Person::Person() { } Person::~Person() { } int Person::operator==(const Person& p) { if (this->name == p.name) { if (this->tel == p.tel) return 0; else return -1; } else return -2; }
List.h文件:
#ifndef LIST_H_ #define LIST_H_ #include <vector> #include "Person.h" class List { public: List(); ~List(); void Showfile();//显示通讯录 int Readfile();//从磁盘读取文件 void Add(); void Reflush();//刷新数据,即重新写入磁盘 void Del(); void Search(); private: std::vector<Person> myfile; }; inline void setout();//输出格式控制 #endif
List.cpp文件:
#include "List.h" #include <iostream> #include <fstream> #include <string> List::List() { } List::~List() { } void setout()//输出格式控制,即左对齐 { std::cout.setf(std::ios_base::left, std::ios_base::adjustfield); } void List::Showfile() { std::vector<Person>::iterator iter; setout(); for (iter = this->myfile.begin(); iter != this->myfile.end(); iter++) { std::cout.width(15);//字域宽度为15 std::cout << iter->name; std::cout.width(15); std::cout << iter->tel << "\n"; } } int List::Readfile() { std::fstream readfile("mylist.txt"); int rows = 0; if (readfile)//如果文件存在 { std::cout << "*******Telephone book********\n"; std::cout << "name:" << "\t\t" << "phone:" << "\n"; Person p; if (!(readfile >> p.name >> p.tel))//如果第一次读取为空 { std::cout << "\tNULL\n"; return 1; } myfile.push_back(p); rows++; while(readfile>>p.name>>p.tel)//读取后存入vector容器中 { rows++; myfile.push_back(p); } this->Showfile(); std::cout << "Total:\t" << rows << "\tinfos\n"; readfile.close(); return rows; } else { std::ofstream outfile;//磁盘中不存在文件的话则创建 outfile.open("mylist.txt"); if (!outfile.is_open()) { std::cout << "file is not created!\n"; return -1; } else { std::cout << "file not exist but we have created one for you!\n"; std::cout << "*******Telephone book********\n"; std::cout << "name:" << "\t\t" << "phone:" << "\n"; std::cout << "\tNULL\n"; } outfile.close(); } return 2; } void List::Reflush() { std::ofstream outfile("mylist.txt"); std::vector<Person>::iterator iter; setout(); for (iter = this->myfile.begin(); iter != this->myfile.end(); iter++) { outfile.width(15); outfile << iter->name; outfile.width(15); outfile << iter->tel << "\n"; } outfile.close(); } void List::Add() { Person p; std::cout << "please input the name:\n"; std::cin >> p.name; std::cout << "please input the phone\n"; std::cin >> p.tel; std::cout << "sucessfully created!\n"; myfile.push_back(p); this->Reflush(); } void List::Del() { if (myfile.empty()) { std::cout << "no info to del!\n"; return; } std::string name; std::cout << "please input the name you want you del:\n"; std::cin >> name; std::vector<Person>::iterator iter; for (iter = this->myfile.begin(); iter != this->myfile.end();) { if (iter->name == name) { myfile.erase(iter);//删除对应项 std::cout << "sucessfully delete!\n"; this->Reflush(); return; } else ++iter; } std::cout << "no info matches!\n"; } void List::Search() { std::string name; std::cout << "please input the name you want to search:\n"; std::cin >> name; std::vector<Person>::iterator iter; for (iter = this->myfile.begin(); iter != this->myfile.end(); iter++) { if (name == iter->name) { std::cout << iter->name << "\t\t" << iter->tel << "\n"; return; } } std::cout << "no info matches!\n"; }
main文件:
// contact.cpp : 定义控制台应用程序的入口点。 // #include "stdafx.h" #include "List.h" #include <stdlib.h> #include <iostream> using namespace std; int Menu() { int num; cout << "********************" << endl; cout << "* 1 ADD *" << endl; cout << "* 2 DEL *" << endl; cout << "* 3 SEARCH *" << endl; cout << "* 4 SHOW *" << endl; cout << "* 5 EXIT *" << endl; cout << "********************" << endl; cout << "input the num:"; cin >> num; return num; } int _tmain(int argc, _TCHAR* argv[]) { List mylist; mylist.Readfile(); int num = Menu(); bool flags = 1; while (flags) { switch (num) { case 1: mylist.Add(); break; case 2: mylist.Del(); break; case 3: mylist.Search(); break; case 4: mylist.Showfile(); break; case 5: cout << "Bye.\n"; return 0; default: cout<<"没有该选项请重输!\n"; break; } cout << "请输入选项:\n"; cin >> num; } system("pause"); return 0; }
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