前几天跟着网上的教程做了一个图书管理体系(c++),但是我增加了收集的元素后发现输出始终为0.0
下列为源码
/*
* @Author: your name
* @Date: 2021-09-18 22:23:13
* @LastEditTime: 2021-09-19 17:23:46
* @LastEditors: Please set LastEditors
* @Description: In User Settings Edit
* @FilePath: \FILE\FILE\C++\book\5.cpp
*/
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
struct bookInfo //图书信息
{
int num; //编号
char name[100]; //书名
char zuozhe[100]; //作者
char chubanshe[100]; //出版社
char riqi[100]; //出版日期
float price; //价格
};
struct tushuguan //存放书籍信息
{
struct bookInfo data;
struct tushuguan* next;
};
struct tushuguan* list=NULL;
struct tushuguan* createHead() //创建表头
{
//动态内存申请
struct tushuguan*headtushuguan=(struct tushuguan*)malloc(sizeof(struct tushuguan));
headtushuguan->next = NULL;
return headtushuguan;
};
// 创建节点
// 把用户的数据变为结构体变量
struct tushuguan* creatatushuguan(struct bookInfo data)
{
struct tushuguan*newtushuguan=(struct tushuguan*)malloc(sizeof(struct tushuguan));
newtushuguan->data = data;
newtushuguan->next = NULL;
return newtushuguan;
};
// 表头插入
void inserttushuguan(struct tushuguan* headtushugaun,struct bookInfo data)
{
struct tushuguan* newtushuguan = creatatushuguan(data);
newtushuguan->next = headtushugaun->next;
headtushugaun->next = newtushuguan;
}
// 表尾插入
// void inserttushuguanByTali(struct tushugaun* headtushugaun, int data)
// {
// struct tushuguan* pMove = headtushugaun;
// while (pMove->next != NULL)
// {
// pMove = pMove->next;
// }
// struct tushuguan* newtushuguan = creatatushuguan(data);
// pMove->next = newtushuguan;
// }
//指定删除
//poseLeft->next=postushuguan->next;
//free(postushuguan);
void deletetushuguanByName(struct tushuguan* headtushuguan,char *bookName)
{
struct tushuguan* posLefttushuguan = headtushuguan;
struct tushuguan* postushuguan = headtushuguan->next;
while (postushuguan != NULL && strcmp(postushuguan->data.name,bookName))
{
posLefttushuguan = postushuguan;
postushuguan = posLefttushuguan->next;
}
//讨论查找结果
if(postushuguan == NULL)
{
return;
}
else
{
printf("删除成功\n");
posLefttushuguan->next=postushuguan->next;
free(postushuguan);
posLefttushuguan =NULL;
}
}
struct tushuguan* searchByName(struct tushuguan* headtushuguan,char* bookName)
{
struct tushuguan* postushuguan = headtushuguan->next;
while (postushuguan !=NULL && strcmp(postushuguan->data.name,bookName))
{
postushuguan = postushuguan->next;
}
return postushuguan;
};
void printList(struct tushuguan* headtushuguan) //演示部分
{
struct tushuguan* pMove = headtushuguan->next;
printf("编号\t书名\t作者\t出版社\t出版日期\t价格\n");
while(pMove!=NULL)
{
printf("%d\t%s\t%s\t%s\t%s\t%.1f\n",pMove->data.num,pMove->data.name,pMove->data.zuozhe,pMove->data.chubanshe,pMove->data.riqi,pMove->data.price);
pMove = pMove->next;
}
}
void makeMenu()//主界面菜单
{
printf("\n\n\n\n\n\t\t\t\t图书信息管理系统\t\t\t\t\n");
printf("\t\t*********************************************\n");
printf("\t\t\t1 ------------------图书信息录入\n");
printf("\t\t\t2 ------------------图书信息浏览\n");
printf("\t\t\t3 ------------------图书信息查询\n");
printf("\t\t\t4 ------------------图书信息删除\n");
printf("\t\t\t5 ------------------图书信息修改\n");
printf("\t\t\t0 -----------------退出图书管理系统\n");
printf("\t\t*********************************************\n");
printf("\t\t请选择:");
}
//文件操作
//存入文件
void saveInfoToFile(const char* fileName,struct tushuguan* headtushuguan)
{
FILE* fp= fopen(fileName,"w");
struct tushuguan*pMove = headtushuguan->next;
while (pMove != NULL)
{
fprintf(fp,"%d\t%s\t%s\t%s\t%s\t%.1f\n",pMove->data.num,pMove->data.name,pMove->data.zuozhe,pMove->data.chubanshe,pMove->data.riqi,pMove->data.price);
pMove = pMove->next;
}
fclose(fp);
}
//读取文件
void readInfoFromFile(const char* fileName,struct tushuguan* headtushuguan)
{
FILE*fp = fopen(fileName,"r"); //第一次打开程序没有文件
if(fp == NULL)
{
//没有文件就新建一个
fp = fopen(fileName,"w+");
}
struct bookInfo tempData;
while (fscanf(fp, "%d\t%s\t%s\t%s\t%s\t%.1f\n",&tempData.num,tempData.name,tempData.zuozhe,tempData.chubanshe,tempData.riqi,&tempData.price) !=EOF)
//while (fscanf(fp, "%s\t%f\t%d\n",tempData.name,&tempData.price,&tempData.num) !=EOF)
{
inserttushuguan(list,tempData);
}
fclose(fp);
}
void keyDown()//交互
{
int userKey = 0;
struct bookInfo tempBook;//产生一个临时变量存放书籍信息
struct tushuguan* result = NULL;
scanf("%d",&userKey);
switch (userKey)
{
case 0:
printf("[退出]\n");
printf("退出成功");
system("pause");
exit(0); //关闭程序
break;
case 1:
printf("[录入]]\n");
printf("请输入录入的图书信息(编号,书名,作者,出版社,出版日期,价格):");
scanf("%d%s%s%s%s%.1f",&tempBook.num,tempBook.name,tempBook.zuozhe,tempBook.chubanshe,tempBook.riqi,&tempBook.price);
inserttushuguan(list,tempBook);
saveInfoToFile("E:\\FILE\\FILE\\C++\\book\\bookinfo.txt",list);
break;
case 2:
printf("[浏览]\n");
printList(list);
break;
case 3:
printf("[查询]\n");
printf("请输入需要查询的书籍名称:");
scanf("%s",tempBook.name);
result = searchByName(list,tempBook.name);
if(result ==NULL)
{
printf("未找到相关信息\n");
}
else
{
printf("编号\t书名\t作者\t出版社\t出版日期\t价格\n");
printf("%d\t%s\t%s\t%s\t%s\t%0.1f\n",result->data.num,result->data.name,result->data.zuozhe,result->data.chubanshe,result->data.riqi,result->data.price);
}
break;
case 4:
printf("[删除]\n");
printf("请输入需要删除的书籍名称:");
scanf("%s",tempBook.name);
deletetushuguanByName(list,tempBook.name);
saveInfoToFile("E:\\FILE\\FILE\\C++\\book\\bookinfo.txt",list);
break;
case 5:
printf("[修改]\n");
printf("请输入需要修改的书籍名称:");
scanf("%s",tempBook.name);
deletetushuguanByName(list,tempBook.name);
saveInfoToFile("E:\\FILE\\FILE\\C++\\book\\bookinfo.txt",list);
printf("请输入修改后的图书信息(编号,书名,作者,出版社,出版日期,价格):");
scanf("%d%s%s%s%s%.1f",&tempBook.num,tempBook.name,tempBook.zuozhe,tempBook.chubanshe,tempBook.riqi,&tempBook.price);
inserttushuguan(list,tempBook);
saveInfoToFile("E:\\FILE\\FILE\\C++\\book\\bookinfo.txt",list);
break;
default:
printf("[输入错误]\n");
break;
}
///自己封装一个edit
}
int main()
{
// 表头输出
// 输出210
// struct tushuguan* list = createHead();
// for(int i = 0; i < 3; i++)
// {
// inserttushuguan(list, i);
// }
// printList(list);
// 表尾输入
// struct tushugaun* list = createtushuguan();
// inserttushuguanByTali(list,1);
// inserttushuguanByTali(list,2);
// printList(list);
list= createHead();
readInfoFromFile("E:\\FILE\\FILE\\C++\\book\\bookinfo.txt",list);
while(1)
{
makeMenu();
keyDown();
system("pause");
system("cls");
}
makeMenu();
system("pause");
}
下面是出错截图
我输入的是648
图书管理系统,参考一下:
#include<stdio.h> //预处理
#include<string.h>
#include<stdlib.h>
#include<conio.h>//定义了通过控制台进行数据输入和数据输出的函数
//定义结构体
struct book
{
int id;
char name[31]; //书名
char author[27]; //作者
char publish[31];//出版社
int store; //库存
int total; //总数
int user[10];
int days[10];
}books[100];
//显示整体标题标题函数
void page_title(char *menu_item)
{
printf("\t\t使用图书馆管理系统\n\n-%s-\n\n",menu_item);
}
//等待返回函数
void return_confirm()
{
printf("\n请按任意键返回……\n");
getch();
}
book_add()
{
int i;
system("cls"); //清屏
page_title("注册新书");
for(i=0;i<12;i++)
{
printf("序号:");
scanf("%d",&books[i].id);
printf("书名:");
scanf("%s",&books[i].name);
printf("作者:");
scanf("%s",&books[i].author);
printf("出版社:");
scanf("%s",&books[i].publish);
printf("数量:");
scanf("%d",&books[i].total);
books[i].store=books[i].total;
printf("\n");
}
}
book_show()
{
int i,flag=0;
system("cls");
for(i=0;i<100;i++)
{
if(strlen(books[i].publish)!=0)
{
printf("编号:%d\t ",books[i].id);
printf("书名:%s\t ",books[i].name);
printf("作者:%s\t ",books[i].author);
printf("出版社:%s\t ",books[i].publish);
printf("库存:%d\t",books[i].store);
printf("总数:%d\n\n",books[i].total);
flag=1;
}
}
if(flag==0)
{
printf("没有找到相关书籍\n");
}
getch();
return i; }
int book_search()
{
int n,i,flag=0;
char nam[30];
system("cls");
printf("请输入书名:");
scanf("%s",&nam);
for(i=0;i<100;i++)
{
if(strcmp(books[i].name,nam)==0)
{
printf("序号:%d\t ",books[i].id);
printf("书名:%s\t ",books[i].name);
printf("作者:%s\t ",books[i].author);
printf("出版社:%s\t ",books[i].publish);
printf("存数:%d\t",books[i].store);
printf("总数:%d\n",books[i].total);
n=i;
flag=1;
getch();
break;
}
}
if(flag==0)
{
printf("\n没有找到相关书籍\n");
getch();
return -1;
}
return n;
}
book_edit()
{
int i,id_change;
system("cls");
page_title("修改图书信息:");
printf("输入要修改的图书id:");
scanf("%d",&id_change);
for(i=0;i<100;i++)
{
if(books[i].id==id_change)
{
printf("修改书名:");
scanf("%s",&books[i].name);
printf("修改作者:");
scanf("%s",&books[i].author);
printf("修改出版社:");
scanf("%s",&books[i].publish);
printf("修改数量:");
scanf("%d",&books[i].total);
printf("修改图书信息成功\n");
books[i].store=books[i].total;
return i;
}
}
printf("\n没有找到相关信息\n");
getch();
return -1;
}
int book_del()
{
int i,num,j;
system("cls");
page_title("删除图书");
printf("输入所要删除的书的id:");
scanf("%d",&num);
for(i=0;i<100;i++)
{
if(books[i].id==num)
{
for(j=i;j<100;j++)
{
books[j].id=books[j+1].id;
strcpy(books[j].name,books[j+1].name);
strcpy(books[j].publish,books[j+1].publish);
printf("该书已经删除了!\n");
getch();
return i;
}
}
}
printf("未找到相关记录\n");
getch();//暂停程序运行,等待键盘IO输入
return -1;
}
//借书
book_out()
{
int n,s,i,d;
system("cls");
page_title("借阅图书");
n=book_search();
if(n!=-1&&books[n].store>0)
{
//赋初值,全为零
for(i=0;i<10;i++)
{
books[n].user[i]=0;
books[n].days[i]=0;
}
printf("借书证序号:");
scanf("%d",&s);
printf("输入可借天数:");
scanf("%d",&d);
books[n].user[0]=s;
books[n].days[0]=d;
books[n].store--;
// 书上这有何意义
// for(i=0;i<10;i++)
// {
// if(books[n].user[i]==0)
// {
// books[n].user[i]=0;
// books[n].days[i]=0;
// break;
// }
// books[n].store--;
// }
}
else if(n!=-1&&books[n].store==0)
{
printf("此书已经完全借完\n\n");
getch();
}
else;
return_confirm();
}
//归还图书
void book_in()
{
int n,s,i;
page_title("归还图书");
n=book_search();
printf("%d",n);
if(n!=-1&&books[n].store<books[n].total)
{
printf("借阅图书证列表\n");
for(i=0;i<10;i++)
{
if(books[n].user!=0)
{
printf("[%d]--%d天\n",books[n].user[i],books[n].days[i]);
}
printf("输入借书证号:");
scanf("%d",&s);
for(i=0;i<10;i++)
{
if(books[n].user[i]==s)
{
books[n].store++;
}
}
}
}
if(n!=-1&&books[n].store==books[n].total)
{
printf("全部归还\n");
}
else if(n!=-1&&books[n].store<books[n].total)
{
printf("归还成功\n");
}
else
;
return_confirm();
}
main()
{
menu:page_title("操作选单");
printf("用数字选择操作\n\n");
printf("\t\t1注册新书\t\t2显示图书\n");
printf("\t\t3查询图书信息\t\t4修改图书信息\n");
printf("\t\t5删除图书\t\t6借阅图书\n");
printf("\t\t7归还图书\t\t8退出系统\n");
printf("请按数字键:\n");
switch(getchar())
{
case'1': book_add();break;
case'2': book_show();break;
case'3': book_search();break;
case'4': book_edit();break;
case'5': book_del();break;
case'6': book_out();break;
case'7': book_in();break;
case'8': exit(0);
}
goto menu;//goto跳转语句
}
别老说输出错误,输入对了吗?你看看你保存和读取文件的代码,只有name和price和num,其它的信息都没有。 fprintf(fp,"%s\t%.1f\t%d\n",pMove->data.name,pMove->data.price,pMove->data.num);
while (fscanf(fp, "%s\t%f\t%d\n",tempData.name,&tempData.price,&tempData.num) !=EOF)