我似乎遇到了永久循环的麻烦，它似乎第一次运行程序时工作但由于某种原因它似乎跳过询问用户是否想要再输入CD的选项..任何帮助将不胜感激，谢谢！
/*
* 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();
}
答案 0 :(得分：0)
尝试在程序中使用这段代码从用户输入中获取字符。 当我在VisualStudio 2012中运行它时，它对我有用。
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;
}
答案 1 :(得分：0)
这应该是正确的版本。每当你想停止等待用户按键时，你应该“吃掉”换行符！这意味着如果你使用scanf从kwyboard获取一些数据，用户将在结尾按Enter键确认获取，输入是存储在输入缓冲区中的换行符，所以我在这里和那里放了一些getchar（）摆脱他们。 fflush（）不起作用，因为它只能强制刷新stdout和stderr。解决方案如下：
#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');
}