学生成绩管理系统20.cpp

这是一个简单的学生成绩管理系统。是我写的第一个可以称的上系统的程序。涉及到了才语言中的文件操作

#include "stdio.h"
#include "string.h"
    struct data
    {
       char names[20];
       long number;
       float score;
     }student;
      char filename[20];
      char names[20];
     
void main()
{
     void createfile();
     void querbynames();
     void querybynumbers();
     void scotbynumber();
     void scotbyscore();
     void add();
     void cansel();
     int a;    
  while(1)
{
     printf("\n");
     printf("\n");
     printf("                          STUDENT SCORES MANAGE SYSTEM");
     printf("                              \n");
     printf("\n");
     printf("\n");
     printf("                                     MENU         \n");
     printf("\n");
     printf("\n");
     printf("             +====================================================+\n");
     printf("             +=========1.Input data and keep score in file========+\n");
     printf("             +=========2.Sort by numbers==========================+\n");
     printf("             +=========3.Sort by score ===========================+\n");
     printf("             +=========4.Query by numbers=========================+\n");
     printf("             +=========5.Query by names===========================+\n");
     printf("             +=========6.Add======================================+\n");
     printf("             +=========7.Delete===================================+\n");
     printf("             +=========8.EXIT=====================================+\n");
     printf("\n");
     printf("Please input your choose:");
          scanf("%d",&a);
           clrscr();
          switch (a)
    {
       case 1: createfile();break;
       case 2: scotbynumber();break;
       case 3: scotbyscore();break;
       case 4: querybynumbers();break;
       case 5: querbynames();break;
       case 6: add();break;
       case 7: cansel();break;
       case 8: exit(0);break;
      default:printf("look carefully!!\n");getch();break;


    }

 }

}
 
   
   
   void createfile()
 {

     FILE *fp;
 
      int count=1;
    printf("Please input filename,the computer can creat file!\n");
    scanf("%s",filename);
    fp=fopen(filename,"w");
        if (fp==NULL)
        {
        printf("can't open file");
        getch();
        exit(1);    
        }


    while(count<=50)
     {
        printf("Please input number,input 0 the porgarm can end\n");
        scanf("%ld",&student.number);
        if(student.number==0)
            break;
          printf("please input name:");
          scanf("%s",student.names);
          printf("please input score:");
          scanf("%f",&student.score);
          if(fwrite(&student,sizeof(student),1,fp)!=1)
           {
              printf("file write error/n");
              
            }
          count++;
    }
      if (count>50)
        printf("\nsorry the record number can't more than 50\n");
        fclose(fp);
  
    printf("Your data is like this :");
    if(( fp=fopen(filename,"r"))==NULL)
     {
        printf("cannot open this file\n");
        getch();
        exit(1);
     }
      
    printf("\n number\t\tname\tscore\n");
        while(fread(&student,sizeof(student),1,fp)!=NULL)
    {
        printf("\n%3ld\t%12s\t%7f\n",student.number,student.names,student.score);
    }
        
   fclose(fp);
   getch();
    } 

   
   
   
   
   
   
   void querbynames()
   {
        FILE *fp;
      struct data
    {
       char names[20];
       long number;
       float score;
    }stu[50];
       char next;
       int result;
       printf("please input filename what record student data\n");
       scanf("%s",filename);

        do
      {     result=0;
            printf("please input names:");
            scanf("%s",names);
            fp=fopen(filename,"r");
      if (fp==NULL)
     {
        printf("can't open file");
        getch();
        exit(1);    
     }
       while(feof(fp)!=1)
        {
               if((fread(&student,sizeof(student),1,fp)!=NULL))
               if(strcmp(names,student.names)==0)
            {
            result=1;
            printf("\n%3ld\t%12s\t%7f\n",student.number,student.names,student.score);
            break;
            }
         }
     fclose(fp);
     if(result==0)
     printf("data not found\n");
     printf("coutinue??(y/n)   ");
     printf("\n");
     next=getche();
     printf("\n");
    
      }while(next=='y'||next=='Y');
  }



 
 
 void querybynumbers()
  {
       FILE *fp;
      struct data
    {
       char names[20];
       long number;
       float score;
     }stu[50];
     char next;
     long no;
     int result;
     printf("please input filename what record student data\n");
     scanf("%s",filename);

        do
      {     result=0;
            printf("please input number:");
            scanf("%ld",&no);
           fp=fopen(filename,"r");
       if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }
    while(feof(fp)!=1)
          {
        if((fread(&student,sizeof(student),1,fp)!=NULL))
        if(student.number==no)
           {
            result=1;
            printf("\n%3ld\t%12s\t%7f\n",student.number,student.names,student.score);
            break;
           }
          }  
    fclose(fp);
    if(result==0)
     printf("data not found\n");
     printf("coutinue??(y/n)   ");
     printf("\n");
     next=getche();
     printf("\n");
    
      }while(next=='y'||next=='Y');
  }

    
     
     void scotbynumber()
{
      FILE *fp;
     struct data
    {
       char names[20];
       long number;
       float score;
     }stu[50];
    
    int count=0;
    int min_a,temp,i,j;
    printf("please input filename what record student data\n");
    scanf("%s",filename);
    fp=fopen(filename,"r");
      if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }
    while((fread(&student,sizeof(student),1,fp)!=NULL))
{   
        stu[count].number=student.number;
        strcpy(stu[count].names,student.names);
        stu[count].score=student.score;
        count++;
 }
  
   
   if(count>1)
    {
       for(i=0;i<count;i++)
        {
               min_a=i;
               for(j=i+1;j<count;j++)
               if(stu[j].number<stu[min_a].number)
               min_a=j;
               temp=stu[min_a].number;
               stu[min_a].number=stu[i].number;
               stu[i].number=temp;
           
        }
    }
        fclose(fp);
        printf("SORT BY NUMBER RESULT IS\n");
        for(i=0;i<count;i++)
      {
        printf("\n%3ld\t%12s\t%7f\n",stu[i].number,stu[i].names,stu[i].score);
      }
         getch();
    }
 
 
 void scotbyscore()
{
     FILE *fp;
     struct data
    {
       char names[20];
       long number;
       float score;
     }stu[50];
   
    int count=0;
    int f,temp,k,max,i;
    printf("please input filename what record student data\n");
    scanf("%s",filename);
    fp=fopen(filename,"r");
      if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }
    while((fread(&student,sizeof(student),1,fp)!=NULL))
{   
        stu[count].number=student.number;
        strcpy(stu[count].names,student.names);
        stu[count].score=student.score;
        count++;
 }
   fclose(fp);
   if(count>1)        
    {
       for(k=0;k<count;k++)
        {
           max=k;
           for(f=k+1;f<count;f++)
       
              if(stu[f].score>stu[max].score)
                    max=f;
              temp=stu[max].score;
              stu[max].score=stu[k].score;
              stu[k].score=temp;
           
        }
    }
        fclose(fp);
        printf("SORT BY SCORE RESULT IS\n");
        for(i=0;i<count;i++)
      {
        printf("\n%3ld\t%12s\t%7f\n",stu[i].number,stu[i].names,stu[i].score);
      
      }
           getch();
}
        



    void add()
    {
        FILE *fp;
     struct data
    {
       char names[20];
       long number;
       float score;
     }stu[50];
   
    int count=0;

    printf("please input filename what record student data\n");
    scanf("%s",filename);
    fp=fopen(filename,"r");
      if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }
        while((fread(&student,sizeof(student),1,fp)!=NULL))
{   
        stu[count].number=student.number;
        strcpy(stu[count].names,student.names);
        stu[count].score=student.score;
        count++;
 }
    fclose(fp);
    fp=fopen(filename,"ab+");
      if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }

 while(count<=50)
     {
        printf("Please input number,input 0 the porgarm can end\n");
        scanf("%ld",&student.number);
        if(student.number==0)
            break;
          printf("please input name:");
          scanf("%s",student.names);
          printf("please input score:");
          scanf("%f",&student.score);
          if(fwrite(&student,sizeof(student),1,fp)!=1)
           {
              printf("file write error/n");
            }
          count++;
    }
      if (count>50)
        printf("\nsorry the record number can't more than 50\n");
        fclose(fp);
  
    printf("Your data is like this :");
    if   (( fp=fopen(filename,"r"))==NULL)
     {
       printf("cannot open this file\n");
        getch();
        exit(1);
     }
      
    printf("\n number\t\tname\tscore\n");
        while(fread(&student,sizeof(student),1,fp)!=NULL)
    {
        printf("\n%3ld\t%12s\t%7f\n",student.number,student.names,student.score);
       }
        
    fclose(fp);
    getch();
    } 

 
    void cansel()
    {
       FILE *fp;
     struct data
    {
       char names[20];
       long number;
       float score;
     }stu[50];
     int count=0;
     int i,n;char y_n,next;
    printf("please input filename what record student data\n");
    scanf("%s",filename);
    fp=fopen(filename,"r");
      if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }
        while((fread(&student,sizeof(student),1,fp)!=NULL))
{   
        stu[count].number=student.number;
        strcpy(stu[count].names,student.names);
        stu[count].score=student.score;
        count++;
 }
    fclose(fp);
            while(1)
        {
           if(count==0)
            { printf("No data in file Any key to continue");
             getch();
             break;
             }
             printf("    sequence    number      name              score   ");
             printf("\n");
           for(i=0;i<count;i++)
               {
                 printf("\n%6d\t%12ld\t%12s\t%12f",i+1,stu[i].number,stu[i].names,stu[i].score);
               }
               printf("\n");
               printf("\n");
                for(i=0;i<count;i++)
               {
               printf("please input sequence number:");
               scanf("%d",&n);
              printf("%ld\t%s\t%f",stu[n-1].number,stu[n-1].names,stu[n-1].score);
              printf("\n");
              printf("\n");
              printf("will be deleted, are you sure?(y/n):");
              getchar();
              y_n=getche();
        if(y_n=='y')
        {
            count--;
            for(i=n-1;i<count;i++)
                stu[i]=stu[i+1];

        }
               }

    printf("\n");
    printf("\n");
    printf("continue to delete?(y/n):");
    next=getche();
    putchar('\n');

    if(next!='Y'&&next!='y')
        break;
  }
  fp=fopen(filename,"w");
      if (fp==NULL)
    {
        printf("can't open file");
        getch();
        exit(1);    
    }
    for(i=0;i<count;i++)
            { 
                   fwrite(&stu[i],sizeof(student),1,fp);
            }
    fclose(fp);
        }