本文實例為大家分享了C++實現簡單通訊錄的具體代碼,供大家參考,具體內容如下
說明:
1 程序中運用到兩個類,一個是Person類,另一個是List類。前者存儲用戶信息,后者主要用于操作,如增刪改查等。但由于本程序中沒有涉及到太復雜的功能,用戶信息可以由一個簡單的結構體表示,但是為了以后拓展方便,和達到學習運算符重載的目的,還是使用了類。
2 List類中的Reflush()方法用戶刷新文件內容,即每次修改了vector后要將最新內容寫入到文件。因此增刪改操作中都要調用該操作,這種方法在數據庫開發中常用到,以小見大。
3 setout()方法設置字符左對齊,便于美觀。另外std::cout.width(15)設置輸出字符域寬度,只對下一次輸出有效。
4 判斷文本文件是否為空還有另一種方法,即string類中的empty()方法,但為了讀取方便沒有采用。
5 其實對于通訊錄的操作只是在類內的vector容器中進行,只有最后刷新的時候同步到磁盤文件中。
6 一些函數中設置多個返回值有利于判斷操作的情況。
Person.h 與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);//重載==運算符,本程序中并沒有用到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();//顯示通訊錄 int Readfile();//從磁盤讀取文件 void Add(); void Reflush();//刷新數據,即重新寫入磁盤 void Del(); void Search();private: std::vector<Person> myfile;}; inline void setout();//輸出格式控制#endifList.cpp文件:
#include "List.h"#include <iostream>#include <fstream>#include <string> List::List(){} List::~List(){} void setout()//輸出格式控制,即左對齊{ 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);//字域寬度為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))//如果第一次讀取為空 { std::cout << "/tNULL/n"; return 1; } myfile.push_back(p); rows++; while(readfile>>p.name>>p.tel)//讀取后存入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;//磁盤中不存在文件的話則創建 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);//刪除對應項 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 : 定義控制臺應用程序的入口點。// #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<<"沒有該選項請重輸!/n"; break; } cout << "請輸入選項:/n"; cin >> num; } system("pause"); return 0;}以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持武林網。
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