Question

int main()
{

    FILE *fp;
    char another = 'Y';
    struct emp
    {
            char name[20];
            int age;
            float bs;
    };
    struct emp e;

    fp = fopen("employee.dat", "w");

    if(fp == NULL)
    {
            printf("file cannot be opened for writing\n");
            exit(1);
    }

    while(another == 'Y')
    {
            printf("\n enter name, age and basic salary: ");
            scanf("%s %d %f", e.name, &e.age, &e.bs);
            fprintf(fp, "%s %d %f\n", e.name, e.age, e.bs);

            printf(" Add another record (Y/N)");
            fflush(stdin);
            scanf("%c", &another);
    }

    fclose(fp);
    return 0;

在这个程序中，我试图将记录写入名为employee.dat的文件中。程序执行正常，但它只需要一个员工记录，然后程序终止。它不是要求添加下一条记录，即

 fflush(stdin); 
 scanf("%c", &another);

未在程序中执行。

提前致谢....

Answer 1

您遇到的问题是scanf("%c", &another);只从输入缓冲区中抓取一个字符。这样就可以了，除了输入缓冲区中仍然有一个新行，因为在输入后点击“输入”。使用getchar()后，您需要清除输入缓冲区：

char c;
while ((c = getchar()) != '\n');

Answer 2

你可以这样做：

while(another == 'Y' || another == 'y')
    {
            printf("\n enter name, age and basic salary: ");
            scanf("%s %d %f", e.name, &e.age, &e.bs);
            fprintf(fp, "%s %d %f\n", e.name, e.age, e.bs);

            printf(" Add another record (Y/N)");

            another=getch();
            //scanf("%c", &another);

    }

Answer 3

您只需使用scanf("\n%c",&another);代替scanf("%c",&another);

即可修复它

scanf("%s %d %f", e.name, &e.age, &e.bs);

示例---＆gt;您输入的内容是：name_1 22 6000.000＆lt;“Enter”＆gt;

然后在缓冲区中：name_1 - ＆gt; e.name 22 - ＆gt; e.age 6000.00 - ＆gt; e.bs＆lt;“Enter”＆gt; - ＆gt;没有

fflush(stdin);//it didn't delete the <"Enter">.
scanf("\n%c", &another);//here we deal with <"Enter">

将记录写入文件：c

3 个答案: