猿博士 2021-04-24 14:48 采纳率: 100%
浏览 163
已采纳

使用c++文件读取ifstream出现了问题，求指点(代码写的有点lj,勿喷)

主要看类Reader，R_b和main函数

 

#include <iostream>
#include <windows.h>
#include <conio.h>
#include<fstream>
#include<stdio.h>
#include<stdlib.h>
#include<iomanip>
#include <string>
#define OK true
#define Error false
#define MAXSIZE 10
typedef bool Status;
typedef int ElemType;
using namespace std;
class R_b;
class Reader;
class Book;
bool flag1=false,flag2=false,flag3=false;
void writetostudenttxt(Reader &r);
void displaystudenttxt(Reader r);
void SetPostion(unsigned short x,unsigned short y)
{
    HANDLE h;
    h=GetStdHandle(STD_OUTPUT_HANDLE);
    COORD pos;
    pos.X=x;
    pos.Y=y;
    SetConsoleCursorPosition(h,pos);
}
void LoginMenu();//登录界面实现
int UserShowMenu()//用户菜单
{
    int choice;
    do
    {
        system("cls");
        printf("-----欢迎来到图书管理系统--用户区---\n");
        printf("     1.图书借阅\n");
        printf("     2.图书续借\n");
        printf("     3.图书归还\n");
        printf("     4.用户图书借阅记录\n");
        printf("     5.返回登录界面\n");
        printf("     6.退出\n");
        cin>>choice;
    }
    while(choice<1||choice>5);
    return choice;
}
int AdminShowMenu()//管理员菜单
{
    int choice;
    do
    {
        system("cls");
        printf("-----欢迎来到图书管理系统--管理员区---\n");
        printf("     1.添加图书\n");
        printf("     2.图书浏览\n");
        printf("     3.修改图书\n");
        printf("     4.删除图书\n");
        printf("     5.添加用户\n");
        printf("     6.删除用户\n");
        printf("     7.查看用户\n");
        printf("     8.返回登录界面\n");
        printf("     9.退出\n");
        cin>>choice;
    }
    while(choice<1||choice>10);
    return choice;
}
class Reader//读者类
{
public:
    char *r_name;
    char *r_id;
    char *brrow;//借书记录
    Reader()
    {
        r_name=new char[20];
        r_id=new char[20];
        brrow=new char[99];
    }
    Reader(char *name,char *id,char *b)
    {
        int len=sizeof(name);
        r_name=new char[len+1];
        len=sizeof(id);
        r_id=new char[len+1];
        len=sizeof(b);
        brrow=new char[len+1];
        strcpy(r_name,name);
        strcpy(r_id,id);
        strcpy(brrow,b);
    }
    ~Reader()
    {
        delete []r_name;
        delete []r_id;
        delete []brrow;
    }
    Reader &operator=(Reader &r)
    {
        if(this==&r)
            return *this;
        int len;
        len=sizeof(r.GetName());
        r_name=new char[len+1];
        len=sizeof(r.Getid());
        r_id=new char[len+1];
        len=sizeof(r.GetBrrow());
        brrow=new char[len+1];
        strcpy(r_name,r.r_name);
        strcpy(r_id,r.r_id);
        strcpy(brrow,r.brrow);
        return *this;
    }
    void input()
    {
        cin>>r_name>>r_id>>brrow;
    }
    char* Getid()
    {
        return r_id;
    }
    char* GetName()
    {
        return r_name;
    }
    char *GetBrrow()
    {
        return brrow;
    }
    void BorrowRecord()//借书记录
    {
        gets(brrow);
    }
    bool Match(char*str,short flag)//fLag=1,与名字进行匹配  flag=2，与学号进行匹配
    {
        return flag==1?strcmp(r_name,str)==0:str==r_id;
    }
    void Display()
    {
        cout<<r_name<<"  "<<r_id<<"  "<<brrow<<endl;
    }
};
class Book//图书类
{
private:
    char b_name[20];//书名
    char b_id[20];//书号
    char auther[20];//作者
public:
    Book() {}
    char *Getid()
    {
        return b_id;
    }
    char *GetName()
    {
        return b_name;
    }
    Book(char *name,char* id,char *a)
    {
        strcpy(name,b_name);
        strcpy(id,b_id);
        strcpy(a,auther);
    }
    bool Match(char*str,short flag)//fLag=1,与名字进行匹配  flag=2，与学号进行匹配   flag=3,与作者名字匹配
    {
        return flag==1?(flag==2?strcmp(b_name,str)==0:strcmp(auther,str)):strcmp(b_id,str)==0;
    }
    void Display()
    {
        cout<<setw(12)<<setiosflags(ios::left)<<b_name<<setw(12)<<b_id<<setw(12)<<auther<<setw(20)<<endl;
    }
};
class R_b//执行操作
{
private:
    Reader reader[MAXSIZE];
    Book book[MAXSIZE];
    int r_size;//读者数量
    int b_size;//书籍数量
public:
    R_b()
    {
        int i,j;
        ifstream is;
        is.open ("STUDENT.txt", ios_base::in |ios_base::binary );
        if(!is) cout<<"文件未打开!"<<endl;
        is.seekg (0, ios_base::end);
        r_size = is.tellg()/sizeof(Reader);
        is.seekg (0, ios_base::beg);
        for( i=0; i<r_size; i++)
        {
            is.read((char*)&reader[i],sizeof(reader[i]));
            //cout<<reader[i].r_name<<"  "<<reader[i].r_id<<"  "<<reader[i].brrow<<endl;
        }
        b_size=0;
        is.close();
    }
    ~R_b() {}
    int Getr_size()
    {
        return r_size;
    }
    bool Pushreader();//添加读者
    int Searchreader();//查看读者情况
    bool Deletereader();//删除用户
    bool Pushbook();//添加图书
    int Searchbook();//查看图书
    bool Deletebook();//删除图书
    bool Borrowbook();//借阅图书
    void r_Display()//用户显示区
    {
        for(int i=0; i<r_size; i++)
            reader[i].Display();
        system("pause");
    }
    void b_Display()//图书展示区
    {
        cout<<endl<<setw(12)<<setiosflags(ios::left)<<"书号"<<setw(12)<<"书名"<<setw(12)<<"作者"<<endl;
        for(int i=0; i<b_size; i++)
            book[i].Display();
        cout<<setiosflags(ios::left);
        system("pause");
    }
};
void writetostudenttxt(Reader &r)
{
    ofstream ofs;
    ofs.open("STUDENT.txt", ios_base::app| ios_base::binary);
    if(!ofs)
    {
        cout<<"打开文件失败!"<<endl;
        return ;
    }
    ofs.write((char*)&r,sizeof(r));
    ofs.close();
}
void displaystudenttxt(Reader r)
{
    ifstream ifs("STUDENT.txt",ios_base::in | ios_base::binary);
    while(ifs.read((char*)&r,sizeof(r)))
        r.Display();
    ifs.close();
}
int main()
{
    //LoginMenu();
    R_b tmp;
    if(tmp.Pushreader()) cout<<"添加成功!"<<endl;
    cout<<tmp.Getr_size()<<endl;//输出STUDENT.txt文件中reader的数量
    tmp.r_Display();
    return 0;
}
bool R_b::Pushreader()
{
    char n[20],i[20],t[99];
    cout<<"请输入姓名：";
    cin>>n;
    int idx;
    cout<<"输入学号：";
    cin>>i;
    for(idx=0; idx<r_size; idx++)
    {
        if(reader[idx].Match(i,2))
        {
            cout<<"学号重复"<<endl;
            system("pause");
            return false;
        }
    }
    cout<<"请说明该同学的借阅情况： ";
    cin>>t;
    Reader tmp(n,i,t);
    cout<<"***"<<endl;
    reader[r_size++]=tmp;
    writetostudenttxt(tmp);
    return true;
}
int R_b::Searchreader()
{
    int choice;
    do
    {
        cout<<"请问你是按照什么条件搜索？1.姓名 2.学号";
        cin>>choice;
    }
    while(choice!=1&&choice!=2);
    char t[20];
    cout<<(choice==1?"姓名":"学号")<<":";
    cin>>t;
    int result=0;
    char nod;
    while(1)
    {
        for(int i=0; i<r_size; i++)
        {
            if(reader[i].Match(t,choice))
            {
                reader[i].Display();
                return i;
            }
            return -1;
        }
        if(result==-1)
        {
            cout<<"没有找到信息";
            system("pause");
            return result;
        }
        cout<<"这是要找的人吗？(y/n)";
        cin>>nod;
        if(nod=='y'||nod=='Y')return result;
        else result++;
    }
}
bool R_b::Deletereader()
{
    char choice;
    short result;
    result=Searchreader();
    if(result==-1) return false;
    cout<<"是否删除这条信息(y/n)";
    cin>>choice;
    short idx;
    if(choice=='Y'||choice=='y')
    {
        for(idx=result; idx<r_size; idx++)
            reader[idx]=reader[idx+1];
        r_size--;
        cout<<"删除成功";
        return false;
    }
    cout<<"信息未删除";
    return true;
}
bool R_b::Pushbook()
{
    char n[20],i[20],a[20];
    cout<<"请输入书名：";
    cin>>n;
    cout<<"请输入作者：";
    cin>>a;
    int idx;
    do
    {
        cout<<"输入书号：";
        cin>>i;
        for(idx=0; idx<b_size; idx++)
            if(book[idx].Match(i,2))
            {
                cout<<"书号重复";
                system("pause");
                break;
            }
    }
    while(idx<b_size);
    Book tmp(n,i,a);
    book[b_size++]=tmp;
    return true;
}
int R_b::Searchbook()
{
    int choice;
    do
    {
        cout<<"请问你是按照什么条件搜索？1.书名 2.书号 3.作者";
        cin>>choice;
    }
    while(choice!=1&&choice!=2&&choice!=3);
    char t[20];
    cout<<(choice==1?"姓名":(choice==2?"学号":"作者"))<<":";
    cin>>t;
    int result=0;
    char nod;
    while(1)
    {
        for(int i=0; i<r_size; i++)
        {
            if(book[i].Match(t,choice))
            {
                book[i].Display();
                return i;
            }
            return -1;
        }
        if(result==-1)
        {
            cout<<"没有找到信息";
            system("pause");
            return result;
        }
        cout<<"这是要找的书吗？(y/n)";
        cin>>nod;
        if(nod=='y'||nod=='Y')return result;
        else result++;
    }
}
bool R_b::Deletebook()
{
    char choice;
    short result;
    result=Searchbook();
    if(result==-1) return false;
    cout<<"是否删除这本书(y/n)";
    cin>>choice;
    short idx;
    if(choice=='Y'||choice=='y')
    {
        for(idx=result; idx<b_size; idx++)
            book[idx]=book[idx+1];
        b_size--;
        cout<<"删除成功";
        system("pause");
        return false;
    }
    cout<<"信息未删除";
    return true;
}

//***************
bool R_b::Borrowbook()//借书
{
    char i[20];
    char i_[20];
    bool f1=false,f2=false;
    int idx,idx_;
    cout<<"请输入借阅者的学号：   ";
    cin>>i;
    for(idx=0; idx<r_size; idx++)
    {
        if(i==reader[idx].Getid())
        {
            cout<<reader[idx].GetName()<<"同学存在!";
            system("pause");
            f1=true;
            break;
        }
    }
    if(!f1)
        return false;

    //******
    do
    {
        cout<<"输入书号：";
        cin>>i_;
        for(idx_=0; idx_<b_size; idx_++)
            if(i_==book[idx_].Getid())
            {
                cout<<"《"<<book[idx].GetName()<<"》"<<"存在！";
                system("pause");
                return false;
            }
    }
    while(idx_<b_size);
    char c;
    cout<<i<<"同学,确认借此书吗?(Y/N)"<<endl;
    cin>>c;
    if(c!='Y'||c!='y')
        return false;
    else
    {
        reader[idx_].BorrowRecord();
    }
    return true;
}
void LoginMenu()
{
    string user="ggq",test1,test2,passwd="123";
    string AmPasswd("asd123"),test3;
    int choice=0;
    char c=0;
    HANDLE h;
    h=GetStdHandle(STD_OUTPUT_HANDLE);

    while(1)
    {
        system("cls");
        SetPostion(35,10);
        SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_GREEN|FOREGROUND_INTENSITY);
        cout<<"图书管理系统"<<endl;
        SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_BLUE|FOREGROUND_INTENSITY);
        if(c==80)//下键
            choice=(choice==4?1:choice+1);
        if(c==72)//上键
            choice=(choice==1?4:choice-1);
        if(c==VK_RETURN && choice==3)//在登录选项退出
        {
            if(test1.empty())
            {
                cout<<"用户名为空!";
                system("pause");
                choice=1;
            }
            else if(test2.empty())
            {
                cout<<"密码为空!";
                system("pause");
                choice=1;
            }
            else
                break;
        }
        if(c==VK_RETURN && choice==4)//在管理员登录选项退出
        {
            if(test3.empty())
                cout<<"密码为空!"<<endl;
            else if(test3==AmPasswd)
            {
                cout<<"密码正确！\n正在进入系统,请稍后...";
                Sleep(3000);
                return ;
            }
            else
            {
                cout<<"用户名或密码错误,请重新输入!"<<endl;
                system("pause");
                flag3=false;
                system("cls");
                LoginMenu();
            }
        }
        SetPostion(25,12);
        if(choice==1)
            SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_GREEN|FOREGROUND_BLUE|FOREGROUND_INTENSITY|BACKGROUND_RED|BACKGROUND_BLUE|BACKGROUND_GREEN);
        cout<<"Username:"<<endl;
        SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_BLUE|FOREGROUND_INTENSITY);
        SetPostion(25,14);
        if(choice==2)
            SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_GREEN|FOREGROUND_BLUE|FOREGROUND_INTENSITY|BACKGROUND_RED|BACKGROUND_BLUE|BACKGROUND_GREEN);
        cout<<"Password:"<<endl;
        SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_BLUE|FOREGROUND_INTENSITY);
        SetPostion(25,16);
        if(choice==3)
            SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_GREEN|FOREGROUND_BLUE|FOREGROUND_INTENSITY|BACKGROUND_RED|BACKGROUND_BLUE|BACKGROUND_GREEN);
        cout<<"Login"<<endl;
        SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_BLUE|FOREGROUND_INTENSITY);
        SetPostion(25,18);
        if(choice==4)
            SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_GREEN|FOREGROUND_BLUE|FOREGROUND_INTENSITY|BACKGROUND_RED|BACKGROUND_BLUE|BACKGROUND_GREEN);
        cout<<"Admin Login"<<endl;
        SetConsoleTextAttribute(h,FOREGROUND_RED|FOREGROUND_BLUE|FOREGROUND_INTENSITY);


        if(c==VK_RETURN && choice==1 && !flag1)
        {
            cin>>test1;
            cout<<endl;
            flag1=true;
        }
        if(c==VK_RETURN && choice==2 && !flag2)
        {
            cin>>test2;
            cout<<endl;
            flag2=true;
        }
        if(c==VK_RETURN && choice==4 && !flag3)
        {
            cout<<"请输入管理员密码："<<endl;
            //system("cls");
            cin>>test3;
            flag3=true;
        }
        if(!c) c=getch();
        c=getch();
    }//while循环体
    if(user!=test1 ||passwd!=test2 )
    {
        cout<<"用户名或密码错误,请重新输入!"<<endl;
        system("pause");
        flag1=false;
        flag2=false;
        system("cls");
        LoginMenu();
    }
    if(user==test1 ||passwd==test2)
    {
        cout<<"登录成功！\n正在进入系统,请稍后...";
        Sleep(3000);
        return ;
    }
}

困惑我好几天了，求指导

 

 

 

  • 写回答

5条回答 默认 最新

  • CSDN专家-赖老师（软件之家） 2021-04-24 17:20
    关注

    参考：

    c++中一次读取整个文件的内容的方法：

    1. 读取至char*的情况
    std::ifstream t;  
int length;  
t.open("file.txt");      // open input file  
t.seekg(0, std::ios::end);    // go to the end  
length = t.tellg();           // report location (this is the length)  
t.seekg(0, std::ios::beg);    // go back to the beginning  
buffer = new char[length];    // allocate memory for a buffer of appropriate dimension  
t.read(buffer, length);       // read the whole file into the buffer  
t.close();                    // close file handle  
  
// ... do stuff with buffer here ...
    1. 读取至std::string的情况：

    第一种方法：

    #include <string>  
#include <fstream>  
#include <streambuf>  
  
std::ifstream t("file.txt");  
std::string str((std::istreambuf_iterator<char>(t)),  
                 std::istreambuf_iterator<char>());

    第二种方法：

    #include <string>  
#include <fstream>  
#include <sstream>  
std::ifstream t("file.txt");  
std::stringstream buffer;  
buffer << t.rdbuf();  
std::string contents(buffer.str());
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论
查看更多回答(4条)

报告相同问题？

悬赏问题

  • ¥15 微信小程序 用oss下载 aliyun-oss-sdk-6.18.0.min client报错
  • ¥15 ArcGIS批量裁剪
  • ¥15 labview程序设计
  • ¥15 为什么在配置Linux系统的时候执行脚本总是出现E: Failed to fetch http:L/cn.archive.ubuntu.com
  • ¥15 Cloudreve保存用户组存储空间大小时报错
  • ¥15 伪标签为什么不能作为弱监督语义分割的结果？
  • ¥15 编一个判断一个区间范围内的数字的个位数的立方和是否等于其本身的程序在输入第1组数据后卡住了(语言-c语言)
  • ¥15 Mac版Fiddler Everywhere4.0.1提示强制更新
  • ¥15 android 集成sentry上报时报错。
  • ¥15 抖音看过的视频，缓存在哪个文件