在我的代码中，我正在读取文件的名称和电话号码，以及与电话号码对应的名称。我在代码中遇到的问题是在加载函数中的for循环之后。
此问题将随机将结构名称的所有值更改为最后分配的名称。另外，我不完全理解如何从拆分标记转换为字符串中的浮点数。
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
struct _data {
char *name;
long number;
};
int SCAN(FILE *(*stream)){
int count;
char dataString[50];
int check = 1;
count = 0;
while(check){
fscanf(*stream, "%s\n", dataString);
fscanf(*stream, "%s\n", dataString);
if (feof(*stream)){
check = 0;
}
count++;
}
return count;
}
struct _data *LOAD(FILE *stream, int size){
int x;
char *tempLine;
size_t length = 0;
const char delim[2] = " ";
char *token;
rewind(stream);
struct _data *array = malloc(sizeof(struct _data) * size);
printf("this is the size: %d\n\n", size);
for(x = 0; x < size; x++){
getline(&tempLine, &length, stream);
token = strtok(tempLine, delim);
//printf("this is inside the for loop of load: %s\n", token);
array[x].name = token;
token = strtok(tempLine, delim);
//printf("this is the token: %s\n", token);
array[x].number = atol(token);
printf("this is name %s, and phone number %ld\n", array[x].name, array[x].number);
}
printf("i am now outside the initial for loop in load\n\n");
for(x = 0; x < size; x++){
printf("this is name %s, and phone number %ld\n", array[x].name, array[x].number);
}
return array;
}
void SEARCH(struct _data *BlackBox, char *name, int size){
int x;
int check = 0;
for(x = 0; x < size; x++){
printf("BlackBox Name: %s, check name: %s\n", BlackBox[x].name, name);
//printf("this is the check: %d\n", strcmp(BlackBox[x].name, name));
if (0 == strcmp(BlackBox[x].name, name)){
printf("*******************************************\n");
printf("The name was found at the %d entry.\n", x);
printf("*******************************************\n");
check = 1;
}
}
if (check == 0){
printf("*******************************************\n");
printf("The name was NOT found.\n");
printf("*******************************************\n");
}
}
void FREE(struct _data *BlackBox, int size){
free(BlackBox);
}
int main(int argv, char **argc){
FILE *fp;
int size;
int x;
struct _data *BlackBox;
if(argv < 2){
printf("*******************************************\n");
printf("* You must include a name to search for. *\n");
printf("*******************************************\n");
}else{
fp = fopen("hw5.data", "r");
size = SCAN(&fp);
BlackBox = LOAD(fp, size);
/* for(x = 0; x < size; x++){
printf("BlackBox Name: %s, check name: %s\n", BlackBox[x].name, argc[1]);
}*/
SEARCH(BlackBox, argc[1], size);
FREE(BlackBox, size);
}
return 0;
}
这是我的意见
ron 7774013
jon 7774014
tom 7774015
won 7774016
bonny 7774017
这是我的输出
ron 0
jon 0
tom 0
won 0
bonny 0
i am now outside the initial for loop in load
bonny 0
bonny 0
bonny 0
bonny 0
bonny 0
最佳答案
您一直在重复使用getline()分配的空间，因此只能看到最后的值。循环后需要将tempLine设置为空，并将length设置为0。您还应该检查getline()中的返回值，以确保您确实有要读取的数据。
对strtok()的第二次调用应该使用空指针。通过重新指定tempLine，可以将名称转换为数字。
getline(&tempLine, &length, stream);
token = strtok(tempLine, delim);
//printf("this is inside the for loop of load: %s\n", token);
array[x].name = token;
token = strtok(tempLine, delim);
^^^ should be NULL!
你应该在打印令牌时发现这个问题。
这段代码可能会按预期工作-但还没有编译。
struct _data *LOAD(FILE *stream, int size)
{
char *tempLine = NULL;
size_t length = 0;
const char delim[] = " ";
char *token;
int x;
rewind(stream);
struct _data *array = malloc(sizeof(struct _data) * size);
printf("this is the size: %d\n\n", size);
for (x = 0; x < size; x++)
{
if (getline(&tempLine, &length, stream) == -1)
{
free(tempLine);
break;
}
token = strtok(tempLine, delim);
// printf("this is inside the for loop of load: [%s]\n", token);
array[x].name = token;
token = strtok(NULL, delim);
// printf("this is the token: [%s]\n", token);
array[x].number = atol(token);
printf("%d: this is name %s, and phone number %ld\n", x, array[x].name, array[x].number);
length = 0;
tempLine = NULL;
}
printf("i am now outside the initial for loop in load\n\n");
for (int i = 0; i < x; i++)
{
printf("%d: this is name %s, and phone number %ld\n", i, array[i].name, array[i].number);
}
return array;
}
还要注意，通常应该避免创建以下划线开头的名称（例如
struct _data）。许多这样的名称是为实现保留的；避免创建以下划线开头的名称是最简单的。