delete.c

商品管理系统 1）进货员对商品基本信息进行输入、删除、修改和查询 （2）销售员对商品的基本信息进行查询和统计 （3）并可以对库存信息进行查询和修改 （4）顾客购买商品

#ifndef DELETE
 #define DELETE
 #include "stdio.h"
 #include "shead.h"
 #include "malloc.h"
 void DelRecord()
 {
  int i,j,k;
  long delnum;/* 存放要删节除的商品编号 */
  product TempS;
  product *s,*t;
  int total=PRODUCTSIZE;/* PRODUCTSIZE在头文件中定义 */
  int recNumber;/* 原文件中的记录数 */
  char DataFile[10]="product",next;
  FILE * fp=NULL;
  s=(product*)malloc(total*sizeof(product));
  if(s==NULL)
  {
   printf("malloc memory fail!End with any key.\n");
   fflush(stdin);
   getch();
   exit(0);
  }
  clrscr();
begin:
  fp=fopen(DataFile,"rb");
  if(fp==NULL)
  {
   printf("\nOpen file %s fail!End with any key\n",DataFile);
   perror("Open file fail");
   fflush(stdin);
   free(s);/* 释放内存空间 */
   getch();
   return;
  }
  /* 输入要删除的商品序号 */
  printf("Please input the product's seatnum withc you want delete:");
  scanf("%ld",&delnum);
  printf("the product you will delete is%ld\n",delnum);
  recNumber=0;
  while(fread(&TempS,sizeof(product),1,fp)!=(int)NULL)
  {
   if(TempS.Number==delnum)
   {
    printf("\nNumber\tName\tPrice\t\tDiscount\t\tmemberPrice\n");
    printf(" %ld\t%.2s\t%.2f\t\t%-8.2f\t\t%.2f\n",TempS.Number,TempS.Name,TempS.price,TempS.discount,TempS.memberprice);
    printf("Do you want delete it(Y/N)?");
    fflush(stdin);
    next=getchar();
    if(next=='y'||next=='Y')
      continue;
   }
   s[recNumber].Number=TempS.Number;
   strcpy(s[recNumber].Name,TempS.Name);
   s[recNumber].price=TempS.price;
   s[recNumber].discount=TempS.discount;
   s[recNumber].memberprice=TempS.memberprice;
   recNumber++;
   if(recNumber>=total)
   {
    total+=PRODUCTINCREASE;
    t=(product*)realloc(s,total*sizeof(product));
    if(t==NULL)
    {
     printf("allot memory fail!\n");
     fflush(stdin);
     getch();
     free(s);
     exit(0);
    }
    s=t;
    t=NULL;
   }
  }
  fclose(fp);
  /* 将删除后的剩余记录写入文工团件 */
  fp=fopen(DataFile,"wb+");
  if(fp==NULL)
  {
   printf("\nOpen file fail!End with any key.\n");
   perror("Open file fail");
   fflush(stdin);
   free(s);/* 释放内存空间 */
   return;
  }
  for(i=0;i<recNumber;i++)
  {
   if(fwrite(&s[recNumber],sizeof(product),1,fp)!=1)
   {
    printf("\nWrite file %s fail!End with any key.\n",DataFile);
    perror("Write File fail");
    fflush(stdin);
    getch();
    free(s);/* 释放内存空间 */
    return;
   }
  }
  fclose(fp);
  /* 显示删除后的文件 */
  fp=fopen(DataFile,"rb");
  if(fp==NULL)
  {
   printf("\nOpen file %s fail!End with any key",DataFile);
   perror("Open file fail");
   fflush(stdin);
   getch();
   free(s);/* 释放内存空间 */
   return;
  }
  printf("the file after delete is:\n");
  printf("\nNumber\tName\t\tprice\t\tdiscount\t\tmemberprice\n");
  while(fread(&TempS,sizeof(product),1,fp)!=(int)NULL)
  {
   if(TempS.Number!=0)
   {
    printf("%ld\t%s\t\t%.2f\t\t%-8.2f\t\t%.2f\n",TempS.Number,TempS.Name,TempS.price,TempS.discount,TempS.memberprice);

   }
  }
  fclose(fp);
  printf("Go on(Y/N)?");
  fflush(stdin);
  next=getchar();
  putchar('\n');
  if(next=='Y'||next=='y') goto begin;
  free(s);/* 释放内存空间 */
 }
#endif