Question

所以我有一个利用openalpr的脚本，并将3个牌照写入文本文件。

文本文件以空行开头，后跟3行，每行6个字符

-imagine a newline here-
JV70BB
JV7OBB
JB7QBB

我希望每个牌照都有一个阵列，但是我有一些麻烦，想知道如何让每一行都成为一个单独的版本。

我该怎么做？

if (ptr_file) {
while ((c = getc(ptr_file)) != EOF)
    //puts license plates into array here
fclose(ptr_file);

Answer 1

加入车牌派对。

fgets()最适合阅读该行。代码使用扫描集来验证条目。

char buf[100];
// Validate empty line
if (fgets(buf, sizeof buf, stdin) == NULL || buf[0] != '\n') {
  Handle_Error();
}

#define LP_N (3)
char *lp[LP_N][7];
int i;
for (i = 0; i < LP_N; i++) {
  if (fgets(buf, sizeof buf, stdin) == NULL) {
    Handle_Error();
  }
  // Adjust per your license plate requirements
  static const char *format = "%6[0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ]";
  if (sscanf(buf, format, &lp[i]) != 1 || strlen(lp) != 6) {
    Handle_Error();
  }
}

BTW：在OP的代码中，c应为int c，以区分EOF与其他char。

Answer 2

尝试：

int i, nb_plate = 3;
FILE *ptr_file = fopen("yourFile.txt", "r+");

char array[10][50]; //you can do malloc... don't forget to free
rewind(ptr_file); //rewind

while(cget(ptr_file) != '\r'); //skip 1st line
for(i=0;i<nb_plate;i++)
fscanf(ptr_file, "%s", &yourArray[i][0]); // get one plate

Answer 3

如果你想逐个字符地阅读文件（看起来很可能看你的代码），只要确保你准备好了6个字符，你应该把它放在任何地方，然后阅读换行符（一个或两个，这些可以是＆＃39; \ r＆＃39;和＆＃39; \ n＆＃39;）。你可以使用一个简单的while循环。

如果你想逐行阅读，只需读取每一行并将其保存在单独的数组中，fgets()应该完成工作（或fscanf()使用正确的格式字符串）。

Answer 4

将fgets()与足够长的缓冲区一起使用，并将缓冲区复制到三个数组中的每一个，具体取决于循环计数器上的模数计算：

#define MAX_LICENSE_PLATE_LENGTH 6

char license_plate_buffer[MAX_LICENSE_PLATE_LENGTH + 2] = {0};
char array_1[MAX_LICENSE_PLATE_LENGTH + 1] = {0};
char array_2[MAX_LICENSE_PLATE_LENGTH + 1] = {0};
char array_3[MAX_LICENSE_PLATE_LENGTH + 1] = {0};

unsigned int counter = 0U;

if (!ptr_file) {
    fprintf(stderr, "Error: No valid file pointer\n");
    exit(EXIT_FAILURE);
}

while (fgets(license_plate_buffer, MAX_LICENSE_PLATE_LENGTH + 2, ptr_file) != NULL) {
    memcpy( (counter % 3 == 0) ? array_1 : ((counter % 3 == 1) ? array_2 : array_3), 
            license_plate_buffer, 
            MAX_LICENSE_PLATE_LENGTH);
    counter++;
}

Answer 5

考虑在循环中使用fgets()来读取文件。它读取整个字符串而不是字符：

FILE *fp = {0};
char buf[260];//arbitrarily big buffer
char strArray[3][7];//simple array, 3 string of 7 char each (enough for NULL terminator)
i = -1;
fp = fopen (path, "r");
if(fp)
{
    while (fgets (buf, 260, fp))//will continue to loop as long as there is a new line
    {
        if(strlen(buf) == 6)   {//check that string length matches that specified in your example code
            i++;                //anything bigger will overflow strArray[i], anything less is not a 
                                //valid license string (according to your current definitions)
            strcpy(strArray[i], buf);
        }   
    }
}
fclose(fp);

Answer 6

much better to use fgets() to read each line of the file

if (ptr_file) 
{
    char licensePlate[10];

    memset( licensePlate, 0x00, sizeof( licensePlate ) );
    if( NULL == fgets( licensePlate, sizeof(licensePlate), ptr_file )
    {
        perror( "fgets failed on first line" );
        exit( EXIT_FAILURE );
    }

    // implied else, fgets successful

    // this was the leading blank line, do, do nothing

    // get first plate
    memset( licensePlate, 0x00, sizeof( licensePlate ) );   
    if( NULL == fgets( licensePlate, sizeof(licensePlate), ptr_file )
    {
        perror( "fgets failed" );
        exit( EXIT_FAILURE );
    }

    // implied else, fgets successful

    if( '\n' == licensePlate[ strlen(licensePlate) )
    {
        licensePlate[ strlen(licensePlate)] = '\0'; // chop off trailing newline
    }
    strcpy( plateArray_1, licensePlate );

    // get second plate
    memset( licensePlate, 0x00, sizeof( licensePlate ) );   
    if( NULL == fgets( licensePlate, sizeof(licensePlate), ptr_file )
    {
        perror( "fgets failed" );
        exit( EXIT_FAILURE );
    }

    // implied else, fgets successful

    if( '\n' == licensePlate[ strlen(licensePlate) )
    {
        licensePlate[ strlen(licensePlate)] = '\0'; // chop off trailing newline
    }
    strcpy( plateArray_2, licensePlate );

    // get third plate
    memset( licensePlate, 0x00, sizeof( licensePlate ) );   
    if( NULL == fgets( licensePlate, sizeof(licensePlate), ptr_file )
    {
        perror( "fgets failed" );
        exit( EXIT_FAILURE );
    }

    // implied else, fgets successful

    if( '\n' == licensePlate[ strlen(licensePlate) )
    {
        licensePlate[ strlen(licensePlate)] = '\0'; // chop off trailing newline
    }
    strcpy( plateArray_3, licensePlate ); 



    fclose(ptr_file);

However, if there were more plates to read, I would make 
the code from memset to strcpy into a sub routine 
and pass in the ptr_file and address of the receiving array

C从3个数组中的文本文件中放入3行

6 个答案: