本文实例为大家分享了C语言就餐管理系统的具体代码，供大家参考，具体内容如下

#include

#include

#include

#define N 20

#define M 20

struct student

{char num[20];

char name[10];

float dietfee;

};

struct diet

{char date[20];

char breakfast[100];

char lunch[100];

char supper[100];

};

void menu();

void reads();

void readss();

void addstudent();

void adddiet();

void addfee();

void query();

void show();

void dele();

void midefy();

void main()

{

int n;

while(1)

{

menu();

printf("\n 请输入您要选择的操作序号：");

scanf("%d",&n);

switch(n)

{case 1: addstudent();break;

case 2: show();break;

case 3: adddiet();break;

case 4: addfee();break;

case 5: query();break;

case 6: dele();break;

case 7: midefy();break;

case 8: exit(0);

default: printf("输入错误！\n ");

}

}

}

void menu()

{printf(" **************************** 食堂就餐餐费管理系统************************ ");

printf("\n 1 添加学生信息");

printf("\n 2 显示学生信息");

printf("\n 3 添加食谱信息");

printf("\n 4 按学号添加餐费");

printf("\n 5 查询某日食谱");

printf("\n 6 删除学生信息");

printf("\n 7 修改学生信息");

printf("\n 8 退出");

}

void reads(struct student stu[N],int *n) //读取学生信息文件

{

FILE *fp;

int i=0;

if((fp=fopen("studenttt.txt","rb"))==NULL)

{ printf("文件打开失败！\n");

return;

}

else

{

*n=getw(fp);

for(i=0;i

fread(&stu[i],sizeof(struct student),1,fp);

}

fclose(fp);

}

void addstudent() //添加学生信息

{FILE *fp;

int n,i,j;

struct student stu;

if((fp=fopen("studenttt.txt","rb+"))!=NULL) //读写

{j=getw(fp);

rewind(fp);

printf("请输入要添加的学生数量：");

scanf("%d",&n);

putw(j+n,fp);

fseek(fp,0L,2); //移动位置指针

for(i=1;i<=n;i++)

{ printf("\n请输入第%d个学生的学号和姓名：\n",i);

scanf("%s%s",stu.num,stu.name);

printf("\n请输入第%d个学生的总餐费：\n",i);

scanf("%f",&stu.dietfee);

fwrite(&stu,sizeof(struct student),1,fp); //向文件写一组数据

}

}

else //文件不存在时，新建一个文件，并将数据写入该文件

{

if((fp=fopen("studenttt.txt","wb"))!=NULL) //只写

{

printf("请输入要添加的学生数量：");

scanf("%d",&n);

putw(n,fp);

for(i=1;i<=n;i++)

{ printf("\n请输入第%d个学生的学号和姓名：\n",i);

scanf("%s%s",stu.num,stu.name);

printf("\n请输入第%d个学生的总餐费：\n",i);

scanf("%f",&stu.dietfee);

fwrite(&stu,sizeof(struct student),1,fp);

}

}

}

fclose(fp);

}

void readss(struct diet die[M],int *t) //读取食谱文件

{

FILE *fp2;

int i=0;

if((fp2=fopen("diet.txt","rb"))==NULL)

{ printf("文件打开失败！\n");

return;

}

else

{

*t=getw(fp2);

for(i=0;i

fread(&die[i],sizeof(struct diet),1,fp2);

}

fclose(fp2);

}

void adddiet() //添加食谱信息

{FILE *fp2;

int n,i,j;

struct diet die;

if((fp2=fopen("diet.txt","rb+"))!=NULL)

{j=getw(fp2);

rewind(fp2);

printf("请输入要添加的食谱数量：");

scanf("%d",&n);

putw(j+n,fp2);

fseek(fp2,0L,2);

for(i=1;i<=n;i++)

{ printf("\n请输入第%d个食谱的日期：\n",i);

scanf("%s",die.date);

printf("\n请输入第%d个食谱的早餐和费用，午餐和费用，晚餐和费用：\n",i);

scanf("%s%s%s",&die.breakfast,&die.lunch,&die.supper);

fwrite(&die,sizeof(struct diet),1,fp2);

}

}

else //文件不存在时，新建一个文件，并将数据写入该文件

{

if((fp2=fopen("diet.txt","wb"))!=NULL)

{

printf("请输入要添加的食谱数量：");

scanf("%d",&n);

putw(n,fp2);

for(i=1;i<=n;i++)

{ printf("\n请输入第%d个食谱的日期：\n",i);

scanf("%s",die.date);

printf("\n请输入第%d个食谱的早餐和费用，午餐和费用，晚餐和费用：\n",i);

scanf("%s%s%s",&die.breakfast,&die.lunch,&die.supper);

fwrite(&die,sizeof(struct diet),1,fp2);

}

}

}

fclose(fp2);

}

void show() //显示学生信息

{struct student stu[N];

int i,n;

reads(stu,&n);

if(n==0)

return;

for(i=0;i

printf("\n 学号： %s姓名: %s餐费：%f\n",stu[i].num,stu[i].name,stu[i].dietfee);

}

void addfee() //添加学生餐费

{struct student stu[N],temp;

int n,i;

float g;

FILE *fp;

printf("\n请输入要增加餐费学生学号：");

scanf("%s",temp.num);

reads(stu,&n);

for(i=0;i

if(strcmp(temp.num,stu[i].num)==0)

break;

if(i>=n)

{printf("无此学生信息!\n");

return;

}

printf("\n请输入增加该学生的餐费数：\n");

scanf("%f",&g);

stu[i].dietfee+=g;

/*strcpy(stu[i].dietfee,temp.dietfee);*/

if((fp=fopen("studenttt.txt","wb"))==NULL)

{printf("打开文件失败！");

return;

}

putw(n,fp);

for(i=0;i

fwrite(&stu[i],sizeof(struct student),1,fp);

fclose(fp);

}

void query() //查询某日食谱信息

{

struct diet die[M];

char date[20];

int i,n;

readss(die,&n);

printf("\n请输入待查询食谱日期：\n");

scanf("%s",date);

for(i=0;i

if(strcmp(date,die[i].date)==0) break;

if(i>=n)

{printf("没有找到该日食谱信息！\n");

return;

}

else

printf("\n 日期：%s早餐%s：午餐：%s晚餐：%s\n",die[i].date,die[i].breakfast,die[i].lunch,die[i].supper);

}

void dele() //删除学生信息

{

struct student stu[N];

struct student stu2[N];

int i,n,m,s;

FILE *fp;

int j;

char num2[20];

printf("请输入要删除的学生学号：");

scanf("%s",&num2);

reads(stu,&n);

if(n==0)

{

printf("没有学生可以删除！");

return;

}

for(m=0,i=0;i

if(strcmp(stu[i].num,num2)!=0)

{

strcpy(stu2[m].num,stu[i].num);

strcpy(stu2[m].name,stu[i].name);

stu2[m].dietfee =stu[i].dietfee;

s=1;

m++;

}else{

continue;

}

}

if(s==0){

printf("该学生不存在！");

return;

} else{

if((fp=fopen("studenttt.txt","wb"))!=NULL) //只写

{

putw(m,fp);

for(j=0;j

{

fwrite(&stu2[j],sizeof(struct student),1,fp);

}

}

fclose(fp);

printf("删除成功！\n");

}

}

void midefy(){ //按照学号修改

struct student stu[N];

struct student stu2[N];

int i,n,m,s;

FILE *fp;

int j;

char num2[20];

printf("请输入要修改的学生学号：");

scanf("%s",&num2);

reads(stu,&n);

if(n==0)

{

printf("没有学生可以修改！\n");

return;

}

for(m=0,i=0;i

if(strcmp(stu[i].num,num2)!=0)

{

strcpy(stu2[m].num,stu[i].num);

strcpy(stu2[m].name,stu[i].name);

stu2[m].dietfee =stu[i].dietfee;

}else{

s=1;

strcpy(stu2[m].num,stu[i].num);

printf("\n你要修改学生的学号为%s：\n",stu[i].num);

printf("\n请输入该学生的姓名:");

scanf("%s",stu2[m].name);

printf("\n请输入该学生的总餐费：\n",i);

scanf("%f",&stu2[m].dietfee);

continue;

}

}

if(s==0){

printf("该学生不存在！\n");

return;

} else{

if((fp=fopen("studenttt.txt","wb"))!=NULL) //只写

{

putw(m,fp);

for(j=0;j

{

fwrite(&stu2[j],sizeof(struct student),1,fp);

}

}

fclose(fp);

printf("修改成功！\n");

}

}