0

プログラムを初めて実行したときは機能しているようですが、何らかの理由で、ユーザーに CD を入力するかどうかを尋ねるオプションがスキップされているようです...何か助けてくださいありがとうございます。

/* 
 * CourseProj.c
 * Create a program (database) that a record shop might use to track its 
    inventory of CDs
 * We need the following fields:
 * - Tittle, Artist, Number of tracks, Album/single, Price
 * This project must be commented
 */

 #include <stdio.h>

 main(){

 char    title [100][61];
 char    artist [100][61];
 int     num_tracks[100];      /* number of tracks on the CD */  
 float   price[100];         
 int     album[100];           /* boolean - is the CD an ALBUM? */
 char    type;                 /* used to read in album/single info */
 int     count = 0;            /* how many Cds are being tracked */
 int     i;                    /* loop counter */


 printf( "Welcome to the CD database.\n");
 printf( "You can store a maximum of 100 CDs.\n");

 /*
  * Loop until they no longer wish to enter any more CDs
  *
  */
 for (;;){      /* forever loops are convenient for this sort of thing */
   /*
    * Ask them if they want to enter another CD
    * Any answer other than y or Y wil be treated as a No
    */
   printf("\nHave you any more CDs to enter (y/n)? ");
   fflush(stdin);
   scanf("%c", &type);
   if (type != 'y' && type !='Y')
     break;


   printf("\n");   /* for neat output */

   // First, the title
   printf("Please enter the details of the CD %d... \n\n", count+1);
   printf("Title? ");
   fflush(stdin);
   scanf("%s", title[count]);


   // input the artist name
   printf("Artist? ");
   fflush(stdin);
   scanf("%s", artist[count]);

   // Now we need to input the number of tracks in the Album
   printf("Number of tracks? ");
   fflush(stdin);
   scanf("%d", &num_tracks[count]);

   // need to check if it's an Album or a single
   for (;;){
     printf("Album or single (a for album, s for single)? ");
     fflush(stdin);
     scanf(" %c", &type);
     if  (type == 'a' || type == 's')
       break;
     printf("Error - only 'a' or 's' are allowed\n");
    }
    album[count] = type == 'a'; // if we get here it must be 'a' or 's'               


    //need to prompt the user for the price of the cd
    printf("Retail price (e.g. 4.65)?");
    fflush(stdin);
    scanf("%f", &price[count]);
    count = count + 1;

    /*
     * Check if we have filled up the array
     */
    if (count == 100){
      printf("You have reached the limits of this program\n\n");
      break;
    }
   }
   /*
    * Output the CD details
    */
   for ( i = 0; i < count; i++){

     printf("\nThe details of CD %d are:\n", i+1);
     printf("==============================\n"); 
     printf("Title: %s\n", title[i]);
     printf("Artist: %s\n", artist[i]);
     printf("Number of track: %d\n", num_tracks[i]);
     //let check what the user input with the boolean


     if (album[i])
       printf("Album\n");

     else
       printf("Single\n");

     printf("Price: %.2f\n", price[i]); 
     printf("===========================\n");


     if ( i < count - 1){ // only do this if there are more CDs to see

     /*
      * A user-friendly way to progress to the next CD
      */
      printf("\nPress ENTER to see the next set of details: ");


      fflush(stdin);
      getchar();
     }
    }

    /*
     * A user-friendly way to exit the program
     */
     printf("\nPress ENTER to exit the program: ");
     fflush(stdin);
     getchar();
    }
4

2 に答える 2

0

これは正しいバージョンである必要があります。ユーザーがキーを押すのを待つのをやめたいときはいつでも、改行を「食べる」必要があります! たとえば、scanf を使用して kwyboard からデータを取得する場合、ユーザーは最後にエンターを押して取得を確認します。そのエンターは入力バッファーに格納された改行であるため、あちこちに getchar() を配置します。それらを取り除くために。fflush() は、stdout と stderr を強制的にフラッシュすることしかできないため、機能しません。解決策は次のとおりです。

#include <stdio.h>

main(){
    char    title [100][61];
    char    artist [100][61];
    int     num_tracks[100];      /* number of tracks on the CD */  
    float   price[100];         
    int     album[100];           /* boolean - is the CD an ALBUM? */
    char    type;                 /* used to read in album/single info */
    int     count = 0;            /* how many Cds are being tracked */
    int     i;                    /* loop counter */


    printf( "Welcome to the CD database.\n");
    printf( "You can store a maximum of 100 CDs.\n");

    /*
    * Loop until they no longer wish to enter any more CDs
    *
    */
    for (;;){      /* forever loops are convenient for this sort of thing */
    /*
     * Ask them if they want to enter another CD
     * Any answer other than y or Y wil be treated as a No
     */
    printf("\nHave you any more CDs to enter (y/n)? ");
    scanf("%c", &type);
    getchar();
    if (type != 'y' && type !='Y')        
        break;

    printf("\n");   /* for neat output */

    // First, the title
    printf("Please enter the details of the CD %d... \n\n", count+1);
    printf("Title? ");

    scanf("%s", title[count]);


    // input the artist name
    printf("Artist? ");

    scanf("%s", artist[count]);

    // Now we need to input the number of tracks in the Album
    printf("Number of tracks? ");
    scanf("%d", &num_tracks[count]);

    // need to check if it's an Album or a single
    for (;;){
        printf("Album or single (a for album, s for single)? ");
        scanf(" %c", &type);
        if  (type == 'a' || type == 's')
            break;
        printf("Error - only 'a' or 's' are allowed\n");
    }
    album[count] = type == 'a'; // if we get here it must be 'a' or 's'               


    //need to prompt the user for the price of the cd
    printf("Retail price (e.g. 4.65)?");
    scanf("%f", &price[count]);
    getchar();
    count = count + 1;

    /*
     * Check if we have filled up the array
     */
    if (count == 100){
        printf("You have reached the limits of this program\n\n");
        break;
    }
    /*
     * Output the CD details
     */
    for ( i = 0; i < count; i++){

        printf("\nThe details of CD %d are:\n", i+1);
        printf("==============================\n"); 
        printf("Title: %s\n", title[i]);
        printf("Artist: %s\n", artist[i]);
        printf("Number of track: %d\n", num_tracks[i]);
        //let check what the user input with the boolean


        if (album[i])
            printf("Album\n");
        else
            printf("Single\n");

        printf("Price: %.2f\n", price[i]); 
        printf("===========================\n");

        if ( i < count - 1){ // only do this if there are more CDs to see
            /*
             * A user-friendly way to progress to the next CD
             */
            printf("\nPress ENTER to see the next set of details: ");
            while(getchar() != '\n');
        }
    }
}
/*
 * A user-friendly way to exit the program
 */
 printf("\nPress ENTER to exit the program: ");
 while(getchar() != '\n');

}

于 2014-02-07T00:11:21.497 に答える
0

このコードのチャンクをプログラムに使用して、ユーザーの入力から文字を取得してみてください。VisualStudio 2012で実行している間、うまくいきました。

printf("\n Have you any more CDs to enter (y/n)? ") ;
fflush(stdin);

type = getchar() ;

if( type == '\n')
{
   break ;
}

printf("you have typed : %c \n",type) ; /*print the character just to make sure that 
                                         it's the right one the user entered. */                                        

if (type != 'y' && type !='Y')
{
  break;
}
于 2014-02-06T20:57:12.480 に答える