我必须从.txt文件中读取如下所示：
New York,4:20,3:03 Kansas City,12:03,3:00 North Bay,16:00,0:20 Kapuskasing,10:00,4:02 Thunder Bay,0:32,0:31
我试图将每个元素分成它自己的数组是最终目标，所以我可以用它来做别的事情。
我的while循环正确读取文件，但只是将文件的最后一行存储在一个数组中，我无法找出原因。读取的文件也可以是任意数量的行。我确信它会读取每一行，因为它会打印出它完美读取的每一行。所以我认为问题在于存储它正在阅读的内容。
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#pragma warning(disable: 4996)
// a function to remove the trailing carriage return
void clearTrailingCarraigeReturn(char *buffer);
/* == FUNCTION PROTOTYPES == */
/* == CONSTANTS == */
#define RECORD_SIZE 256
#define NUM_RECORDS 5
#define CHUNK_SIZE 1024
#define STRING_SIZE 80
// MAIN
int main(int argc, char *argv[]) {
FILE *fp;
char flightInfo[RECORD_SIZE] = { 0 };
char cityName[20] = {};
char flightHour[20] = {};
char flightMin[20] = {};
char layoverHour[20] = {};
char layoverMin[20] = {};
int i = 0;
struct flightInfo {
char flightName[20];
double flightTime;
double layoverTime;
};
fp = fopen(argv[1], "r");
// first - we'll check the command-line arguments to ensure that the user specified
// a single argument - which we will assume is the name of a file
if (argc != 2) {
printf("Sorry - you need to specify the name of a file on the command line.\n");
return -1;
}
if (fp == NULL) {
printf("Can't open the TEXT file for reading\n");
return -4;
}
// get each of the lines from the file
while (fgets(flightInfo, sizeof flightInfo, fp) > 0) {
clearTrailingCarraigeReturn(flightInfo);
// display the line we got from the file
printf(" >>> read record [%s]\n", flightInfo);
}
// we exited the reading loop - was it because we read the EOF?
if (feof(fp)) {
printf(" [DONE reading the file ... we've reached the EOF]\n");
} else {
// we exited the loop because of an error
if (ferror(fp)) {
// there's an error
printf("Error reading a record from the file\n");
if (fclose(fp) != 0) {
// we can't even close the file
printf("Can't close the TEXT file we opened for reading\n");
}
return -5;
}
}
}
// This function locates any carriage return that exists in a record
// and removes it ...
void clearTrailingCarraigeReturn(char *buffer) {
char *whereCR = strchr(buffer, '\n');
if (whereCR != NULL) {
*whereCR = '\0';
}
}
您的代码中存在多个问题：
fgets()返回一个指向目标数组或NULL的指针，所以你不应该使用> 0而是这样：
while (fgets(flightInfo, sizeof flightInfo, fp) != 0)
'\n'称为换行符，而不是回车符。在传统平台上，\n在文本文件0D 0A中转换为2个字节，即：回车和换行。flighInfo结构数组中的下一个条目：
if (sscanf(flightInfo, "%19[^,],%2[0-9]:%2[0-9],%2[0-9]:%2[0-9]",
cityName, flightHour, flightMin, layoverHour, layoverMin) == 5) {
/* convert the times into `double` values and store the info */
} else {
/* report the error, exit */
}
struct flightInfo标签和char数组使用相同的名称。这很容易让人感到困惑和容易出错。你应该重命名char数组line或buf。您没有存储扫描结果。这些线：
while (fgets(flightInfo, sizeof flightInfo, fp) > 0)
{
clearTrailingCarraigeReturn(flightInfo);
// display the line we got from the file
printf(" >>> read record [%s]\n", flightInfo);
}
将下一行读入flightInfo（这是一个char数组），当下一行重新读入flightInfo的开头时。最后一行读取将存储在flightInfo中。
如果你想保留它，你也需要存储该行。 EG，你可以这样做：
char multiple_flight_info[100][1024];
int i = 0;
while (fgets(multiple_flight_info[i], 1024, fp) > 0)
{
clearTrailingCarraigeReturn(flightInfo[i]);
// display the line we got from the file
printf(" >>> read record [%s]\n", flightInfo);
i++;
if (i > 100) { exit(1); } /* do better error exiting here */
}
基本上这会创建一个双数组。第一个索引是要读取的行号，第二个索引是读取行中的字符位置。
还有很多事情需要做才能“安全”而不是阅读部分线条，因为一个太长，等等。但这可能会让你开始。