在 C 中扫描文件

Question

所以我的文本文档中有以下内容：

7
PERSON Sarah 20 5 50
PERSON Jordan 30 10 30
PERSON James 25 42 56.50
GROUP STEEL 2
Martin 21 5 80.50
Martha 25 10 79.75
PERSON Hector 38 10 100.50
PERSON Charles 18 5 35
GROUP LUMBER 3
Jill 19 5 91
Aaron 25 10 98
Mark 28 42 152.80

所以我试图让我的代码循环遍历此处的所有名称并打印出信息。名字代表人名，第一个数字代表年龄，第二个数字代表公里数运行，第三个数字代表募集金额。 PERSON 代表一个人，而 group 代表多个人。第一行的7代表PERSONS和GROUPS的总数；有 5 个标记为 PERSON 的人和 2 个标记为 GROUP 的组。

但是，我的代码只打印出每个人的信息，标签为 PERSON。我怎样才能让我的代码打印组的名称及其成员的信息？这是我的代码（不完整，但为了展示我正在尝试做的事情）：

FILE * ifp = fopen("race01.txt", "r");
int numPeople, i, num = 1;
struct person individual;

fscanf(ifp, "%d", &numPeople);

for(i = 0; i < numPeople; i++) {
        fscanf(ifp, "%s %s %d %d %f", individual.name, individual.name, &individual.age, &individual.event, &individual.money);

        if (individual.event == 42) {
            printf("%s registered for the marathon race! They have been assigned the number %d\n", individual.name, num);
        }
        else {
            printf("%s registered for the %dk race! They have been assigned the number %d\n", individual.name, individual.event, num);
        }

        num++;
    }

我尝试了各种变体，从嵌套的 for 循环到额外的扫描线，但似乎没有什么可以涵盖 "groups"。

Answer 1

正如 Jonathan 所说，您应该检查您读取的第一个字符串是“PERSON”还是“GROUP”。如果它等于“PERSON”，您将读取有关此人的信息（姓名、年龄等...），如果它等于“GROUP”，您应该读取该组中的人数，然后读取该组中每个人的信息团体。使用像“strcmp”这样的函数来比较两个字符串。我在下面有您的代码的修改版本，它编译并且工作正常。我创建了一个名为“print_raceinfo”的函数，它打印关于一个人的信息

#include<stdio.h>
#include<math.h>

#define NAME_MAX 25

struct person {
   char name[NAME_MAX];
   int age;
   int event;
   float money;
};

void print_raceinfo(struct person individual, int num)
{
    if (individual.event == 42) {
        printf("%s registered for the marathon race! They have been assigned the number %d\n", individual.name, num);
    }
    else {
        printf("%s registered for the %dk race! They have been assigned the number %d\n", individual.name, individual.event, num);
    }
}

int main(){

    FILE *fp;
    int numPeople, i, num = 1;
    struct person individual;
    char person_or_group[NAME_MAX];
    char group_name[NAME_MAX];
    int numpeople_in_group, j;

    fp = fopen("F://repoexample/race.txt", "r+");
    fscanf(fp, "%d", &numPeople);

    for(i = 0; i < numPeople; i++) {

        fscanf(fp, "%s", person_or_group);

        //Compare the first 6 characters of string person_or_group with "PERSON"
        if (strncmp(person_or_group, "PERSON", 6) == 0) {

            fscanf(fp, "%s %d %d %f", individual.name, &individual.age, &individual.event, &individual.money);

            print_raceinfo(individual, num);

            num++;
        }
        else if (strncmp(person_or_group, "GROUP", 5) == 0){

                //Read group name and number of people in that group
                fscanf(fp, "%s %d", group_name, &numpeople_in_group);

                for (j = 0; j<numpeople_in_group; j++) {

                    //Extract information for each person in that group
                    fscanf(fp, "%s %d %d %f", individual.name, &individual.age, &individual.event, &individual.money);

                    print_raceinfo(individual, num);

                    num++;
                }
        }

   }

    printf("Total number of persons = %d\n", num - 1);

    return 0;
}

输出：

在 C 中扫描文件

Scanning through a file in C

c

loops

file

scanning