fig23_08.c

来自「经典vc教程的例子程序」· C语言 代码 · 共 81 行

/* Credit inquiry program */
#include <stdio.h>

main()
{
   int request, account;
   float balance;
   char name[30];
   FILE *cfPtr;

   if ((cfPtr = fopen("clients.dat", "r")) == NULL)
      printf("File could not be opened\n");
   else {
      printf("Enter request\n"
             " 1 - List accounts with zero balances\n"
             " 2 - List accounts with credit balances\n"
             " 3 - List accounts with debit balances\n"
             " 4 - End of run\n? ");
      scanf("%d", &request);

      while (request != 4) {
         fscanf(cfPtr, "%d%s%f", &account, name, &balance);

         switch (request) {
            case 1:
               printf("\nAccounts with zero balances:\n");

               while (!feof(cfPtr)) {

                  if (balance == 0)
                     printf("%-10d%-13s%7.2f\n", 
                            account, name, balance);

                  fscanf(cfPtr, "%d%s%f", 
                         &account, name, &balance);
               }

               break;
            case 2:
               printf("\nAccounts with credit balances:\n");

               while (!feof(cfPtr)) {

                  if (balance < 0)
                     printf("%-10d%-13s%7.2f\n", 
                            account, name, balance);

                  fscanf(cfPtr, "%d%s%f", 
                         &account, name, &balance);
               }

               break;
            case 3:
               printf("\nAccounts with debit balances:\n");

               while (!feof(cfPtr)) {

                  if (balance > 0)
                     printf("%-10d%-13s%7.2f\n", 
                            account, name, balance);

                  fscanf(cfPtr, "%d%s%f", 
                         &account, name, &balance);
               }

               break;            
         }      

         rewind(cfPtr);
         printf("\n? ");
         scanf("%d", &request);
      }

      printf("End of run.\n");
      fclose(cfPtr);
   }

   return 0;
}