c语言函数成绩排序输出 c语音成绩排序( 二 )


/*删除学生信息*/
void Student_Delete()
{
int i;
while(1)
{
char id[20];
int index;
printf("请输入要删除的学生的学号:");
scanf("%s",id);
getchar();
index=Student_SearchByIndex(id);
if (index==-1)
{
printf("学生不存在!\n");
}
else
{
printf("你要删除的学生信息为:\n");
Student_DisplaySingle(index);
printf("是否真的要删除?(y/n)");
if (getchar()=='y')
{
for (i=index;inum-1;i++)
{
students[i]=students[i+1];//把后边的对象都向前移动
}
num--;
}
getchar();
}
printf("是否继续?(y/n)");
if (getchar()=='n')
{
break;
}
}
}

/*按姓名查询*/
void Student_Select()
{
while(1)
{
char name[20];
int index;
printf("请输入要查询的学生的姓名:");
scanf("%s",name);
getchar();
index=Student_SearchByName(name);
if (index==-1)
{
printf("学生不存在!\n");
}
else
{
printf("你要查询的学生信息为:\n");
Student_DisplaySingle(index);
}
printf("是否继续?(y/n)");
if (getchar()=='n')
{
break;
}
}
}

/*按平均值排序*/
void Student_SortByAverage()
{
int i,j;
struct Student tmp;
for (i=0;inum;i++)
{
for (j=1;jnum-i;j++)
{
if (students[j-1].Averagestudents[j].Average)
{
【c语言函数成绩排序输出 c语音成绩排序】tmp=students[j-1];
students[j-1]=students[j];
students[j]=tmp;
}
}
}
}

/*显示学生信息*/
void Student_Display()
{
int i;
printf("%10s%10s%8s%8s%8s%10s\n","学号","姓名","成绩","成绩","成绩","平均成绩");
printf("-------------------------------------------------------------\n");
for (i=0;inum;i++)
{
printf("%10s%10s%8.2f%8.2f%8.2f%10.2f\n",students[i].ID,students[i].Name,
students[i].Mark1,students[i].Mark2,students[i].Mark3,students[i].Average);
}
}

/*将学生信息从文件读出*/
void IO_ReadInfo()
{
FILE *fp;
int i;
if ((fp=fopen("Database.txt","rb"))==NULL)
{
printf("不能打开文件!\n");
return;
}
if (fread(num,sizeof(int),1,fp)!=1)
{
num=-1;
}
else
{
for(i=0;inum;i++)
{
fread(students[i],sizeof(struct Student),1,fp);
}
}
fclose(fp);
}

/*将学生信息写入文件*/
void IO_WriteInfo()
{
FILE *fp;
int i;
if ((fp=fopen("Database.txt","wb"))==NULL)
{
printf("不能打开文件!\n");
return;
}
if (fwrite(num,sizeof(int),1,fp)!=1)
{
printf("写入文件错误!\n");
}
for (i=0;inum;i++)
{
if (fwrite(students[i],sizeof(struct Student),1,fp)!=1)
{
printf("写入文件错误!\n");
}
}
fclose(fp);
}


/*主程序*/
void main()
{
int choice;
IO_ReadInfo();
while(1)
{
/*主菜单*/
printf("\n------ 学生成绩管理系统------\n");
printf("1. 增加学生记录\n");
printf("2. 修改学生记录\n");
printf("3. 删除学生记录\n");
printf("4. 按姓名查询学生记录\n");
printf("5. 按平均成绩排序\n");
printf("6. 退出\n");
printf("请选择(1-6):");
scanf("%d",choice);
getchar();
switch(choice)
{
case 1:
Student_Insert();
break;
case 2:
Student_Modify();
break;
case 3:
Student_Delete();
break;

推荐阅读