C - 读取文件和 strtok 到数组

Question

我正在尝试标记文件并将标记保存到名为 tokenize 的函数内的数组中。然后我想获取要在 main 或其他函数中使用的 tokenize 函数的输出，以执行某些操作。

问题是:我不太确定如何在标记文件行后在 main 函数中向前移动指针。目标是将标记化的行保持组合在一起而不是分开，这样单词的意思就不会丢失。

file.txt 看起来像(为了便于阅读，在\t 之间添加了空格):

948213843 \t 644321498 \t 16549816514 \t 13616131216 \t 1646312132 \t 13468486

我的问题:我如何才能访问从 tokenize 函数返回的数组信息？

谢谢!

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define SIZE 1024

char *tokenize(char *buffer, char *pattern)
{
        int i = 0;
        int j;
        char *arr[15];

        char *token = strtok_r(buffer, "\t", &buffer);
        for (j=0; j < 15; j++)
                arr[j] = malloc(strlen(buffer) * sizeof(char));

        // pattern matching removed to focus only on tokenization
        while (token != NULL)
        {
                strcpy(arr[i], token);
                printf("%s\n", token);
                token = strtok_r(NULL, "\t", &buffer);
                i++;
        }

        // test to verify array data --- good here
        for (i=0; i < 15; i++)
                fprintf(stdout, "test: %s\n", arr[i]);

        return *arr;
}

int main(int argc, char *argv[])
{
        FILE            *filename;
        static char     buffer[SIZE];

        filename = fopen("file_name.txt", "rb+");
        if (filename != NULL)
        {
                while (fgets(buffer, SIZE, filename) != NULL)
                {
                        if (buffer[strlen(buffer) - 1] == '\n')
                        {
                                buffer[strlen(buffer) - 1] = '\0';

                                // the matching search pattern will grab the line of data to be tokenized
                                char *token = tokenize(buffer, "948213843");


                                // test print -- not good here
                                if (token != NULL)
                                {
                                        for (int i=1; i < 15; i++)
                                                fprintf(stdout, "sucks: %s\n", token);
                                }

                                // do something with the tokens
                                // doSomethingWithToken(token);
                        }
                }
        }
}

Answer 1

您的代码中有许多错误。我已在下面的代码中修复了我可以找到的那些，我在其中使用了三重斜杠 (///) 来标记我所做的更改。

但是，主要问题是您的 arr[] 被定义为字符串数组(字符指针)，但您正试图处理它(在 main ) 作为单个字符串。

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define SIZE 1024

char** tokenize(char* buffer, char* pattern) /// You want to return an ARRAY of pointers (array of strings)!
{
    int i = 0;
    int j;
    static char* arr[15]; /// Without the static keyword, the array is lost when the function returns

    char* token = strtok_r(buffer, "\t", &buffer);
    for (j = 0; j < 15; j++) {///
        arr[j] = malloc((strlen(buffer) + 1) * sizeof(char)); /// Need to add 1 char for nul terminator
        strcpy(arr[j], ""); /// Put in an empty string!
    }///
    // pattern matching removed to focus only on tokenization
    while (token != NULL)
    {
        strcpy(arr[i], token);
        printf("%s\n", token);
        token = strtok_r(NULL, "\t", &buffer);/// Oops! I've undone this change.
        i++;
    }

    // test to verify array data --- good here
    for (i = 0; i < 15; i++)
        fprintf(stdout, "test: %s\n", arr[i]);

    return arr; /// This now returns the array of string pointers!
}

int main(int argc, char* argv[])
{
    FILE* filename;
    static char     buffer[SIZE];

    filename = fopen("file_name.txt", "rb+");
    if (filename != NULL)
    {
        while (fgets(buffer, SIZE, filename) != NULL)
        {
            if (buffer[strlen(buffer) - 1] == '\n')
            {
                buffer[strlen(buffer) - 1] = '\0';

                // the matching search pattern will grab the line of data to be tokenized
                char** token = tokenize(buffer, "948213843"); /// Change this to match new function definition!

                // test print -- not good here
                if (token != NULL)
                {
                    for (int i = 1; i < 15; i++)
                        fprintf(stdout, "sucks: %s\n", token[i]); /// Need to give index to each string!
                }

                // do something with the tokens
                // doSomethingWithToken(token);

                /// Clean-up: Free the arrays...
                if (token != NULL)
                {
                    for (int i = 1; i < 15; i++)
                        free(token[i]);
                }

            }
        }
    }
    return 0;///
}

没有可用的数据文件，我无法测试它；另外，我的 MSVC 系统没有 strtok_r 函数，但我认为您调用的是正确的。

随时要求进一步澄清和/或解释。