用c++编写一个简单的登录系统-笔记

原文：

https://blog.csdn.net/qq_34289221/article/details/52674908

 

修正了下。

---------------------------------------------------

CGUI.ccp：

#include<iostream>
#include <cstdio>
#include "cdbase.h"
using namespace std;
class CGUI
{
public:
 CGUI() :_running(true) {}
 void run();
 void showmainmenu()       //主页面
 {
  cout << "****************" << endl;
  cout << "    1.登录      " << endl;
  cout << "    2.注册      " << endl;
  cout << "    3.退出      " << endl;
  cout << "****************" << endl;
 }
 void dologin()           //登陆页面
 {
  cout << "请输入登录名:" << endl;
  gets_s(_name);
  cout << "请输入密码:" << endl;
  gets_s(_pwd);
  if (_db.CheckUserAuth(_name, _pwd))
  {
   cout << "登陆成功" << endl;
  }
  else
  {
   cout << "用户名或密码错误！" << endl;
  }
 }
 void doregister()            //注册页面 
 {
  cout << "欢迎注册" << endl;
  cout << "请输入注册名称" << endl;
  gets_s(_name);
  cout << "请输入密码:" << endl;
  gets_s(_pwd);
  if (_db.query(_name))
  {
   cout << "该用户已经注册过,请重新填写" << endl;
  }
  else
  {
   _db.WriteUserInfo(_name, _pwd);
   cout << "用户名" << _name << "注册成功" << endl;
  }
 }
 void doexit()                   //退出页面
 {
  exit(0);
 }
private:
 char _name[20];
 char _pwd[20];
 bool _running;
 CDBase _db;
};
typedef void (CGUI::* pfunc)();
typedef struct _tableitem
{
 int choice;
 pfunc pfunc;
}tableitem;
tableitem gtable[] =
{
{1,&CGUI::dologin},
{2,&CGUI::doregister},
{3,&CGUI::doexit}
};
int gtablelen = sizeof(gtable) / sizeof(gtable[0]);
void CGUI::run()
{
 int chioce;
 while (_running)
 {
  showmainmenu();
  cout << "请选择：" << endl;
  cin >> chioce;
  //getchar();
  //switch语句或for循环都可以，不过后者更适用于公司编写
  /*switch(choice)
  {
  case 1:
   dologin();
   break;
  case 2:
   doregister();
   break;
  case 3:
   doexit();
   break;
  }*/
  for (int i = 0; i<gtablelen; i++)
  {
   if (chioce == gtable[i].choice)
   {
    (this->*gtable[i].pfunc)();
   }
  }
 }
}
int main()
{
 CGUI gui;
 gui.run();
 return 0;
}

CDBase.h：

#ifndef CIRCLE_H
#define CIRCLE_H
#include <iostream>
using namespace std;
class CDBase
{
public:
 CDBase()
 {
  _phead = new Node();
 }
 ~CDBase()
 {
  Node* ptr = _phead;
  while (ptr != NULL)
  {
   _phead = _phead->_pnext;
   delete ptr;
   ptr = _phead;
  }
 }
 bool CheckUserAuth(char* name, char* pwd) //判断用户名、密码是否匹配
 {
  Node* ptr = _phead->getNext();
  while (ptr != NULL)
  {
   if ((strcmp(name, ptr->_name) == 0 && strcmp(pwd, ptr->_pwd) == 0))
    return true;
   ptr = ptr->getNext();
  }
  return false;
 }
 bool query(char* name) //名字是否匹配
 {
  Node* ptr = _phead->getNext();
  while (ptr != NULL)
  {
   if (strcmp(name, ptr->_name) == 0)
    return true;
   ptr = ptr->getNext();
  }
  return false;
 }
 void WriteUserInfo(char* name, char* pwd)
 {
  Node* pnode = new Node(name, pwd);
  pnode->sexNext(_phead->getNext());
  _phead->sexNext(pnode);
 }
private:
 struct Node
 {
  Node() :_pnext(NULL) {}
  Node(char* n, char* p) :_pnext(NULL)
  {
   strcpy_s(_name, n);
   strcpy_s(_pwd, p);
  }
  char _name[20];
  char _pwd[20];
  Node* _pnext;
  void sexNext(Node* p)
  {
   _pnext = p;
  }
  Node* getNext()
  {
   return _pnext;
  }
 };
 Node* _phead;
};
#endif