Question

目前,我有行文为4行的法典,我希望能够改变这一条,直到地球观测组织或我的最高价。我无法得到! 亲爱阵工作,并问我如何改变我的法典以实现这一目标?

预收

#include <stdio.h>

struct record{
    char name[2];
    int arrival_time;
    int job_length;
    int job_priority;
};

const int MAX = 40;

int main(void)
{
    struct record jobs[MAX];
    int i = 0;
    int j;
    FILE *f = fopen("data.dat","rb");

    while (fscanf(f, "%s %d %d %d", &jobs[i].name, &jobs[i].arrival_time,
                  &jobs[i].job_length, &jobs[i].job_priority) == 4 && i < MAX)
      i++;

    for (j = 0; j < i; j++)
        printf("%s %d %d %d
", jobs[j].name, jobs[j].arrival_time,
               jobs[j].job_length, jobs[j].job_priority);

    fclose(f);

    return(0);
}

Answer 1

类似于

while (fscanf(f, "   %s   ", &etc) != EOF) {

}

然后使用< 编码>feof(f),以检查其是否为fscanf。页: 1

Answer 2

你的法典似乎做了你想要做的事,但:

char name[2];

姓名可能超过1名。

FILE *f = fopen("data.dat","rb");

You seem to be reading text ("r") file, not binary ("rb").

<代码>&jobs[i], 姓名: 姓名:<0>。

Answer 3

您需要修改以下表格中的测试顺序:while() loop-, 您必须测试i < <>m>, 电话:fscanf(, 否则,你可以多次使用(还应通过jobs[i] 姓名而无需&fscanf):

while (i < MAX && fscanf(f, "%s %d %d %d", jobs[i].name, &jobs[i].arrival_time,
              &jobs[i].job_length, &jobs[i].job_priority) == 4)

Answer 4

在个人方面,我要这样说:

for(i=0 ; i<MAX ; ++i) {
    fscanf(f, "%s %d %d %d", &jobs[i].name, &jobs[i].arrival_time,
           &jobs[i].job_length, &jobs[i].job_priority);
    if(ferror(f)  ||  feof(f)) break;
}

The key point is that, at the best of my knowledge, you cannot know that a file is come to end without trying to read it. That is the reason why I check feof() and ferror() after having read data. At the end of the loop, the variable i contains the number of read data

友情链接