c - 如何在C语言的函数中添加记录(结构体)？

Question

如果将记录作为参数发送给函数，如何添加记录？

struct record {
char name[20];
int nr;
};

void AddRecord(struct record **p_allRecs, int p_size);

int main() {

struct record *allRecs;
/* putting in some records manually, size++... */
allRecs = (struct record *)malloc(size*sizeof(struct record));
}

AddRecord(&allRecs, size);/* wan't to add a record like this */
}/* end main */

void AddRecord(struct myRecord **p_allRecs, int p_size){
int i;
struct record *allRecsTemp; /* temporary */
allRecsTemp = (struct record *)malloc((p_size+1)*sizeof(struct record));/* oneup */
/* first copy existing recs */
for(i = 0; i < p_size; i++) {
strcpy(allRecsTemp[i].name, p_allRecs[i]->name);/* this want't work */
allRecsTemp[i].nr = p_allRecs[i]->nr;/* this want't work */
}
/* then ask for new record */
printf("Name?");
    scanf("%s", &allRecssTemp[p_size].name);
    printf("Nr? ");
    scanf("%d", &allRecsTemp[p_size].nr);
    p_size++;
    free(p_allRecs);
    p_allRecs = allRecsTemp;

Answer 1

在 C 中，可以对结构体进行赋值。因此，您可以这样说:

allRecsTemp[i] = (*p_allRecs)[i];

不需要调用 strcpy() 等。这样做应该会简化您的代码。哦，还有:

free(p_allRecs);
p_allRecs = allRecsTemp;

应该是:

free( * p_allRecs );
* p_allRecs = allRecsTemp;

记住 - p_allRecs 是指向指针的指针，而 allRecsTemp 只是一个指针。