Question

我正在尝试解析使用逗号作为delim的csv 我有几个字段在他们中使用逗号，但有他们周围的引号继承人我尝试n解析，但似乎每次都跳过if，即使使用以引号开头的测试数据？

          // special case "run,fly,jump"
        tokholder = strsep(&lineholder, ", \n");//gets next token of the line


        //to handle special cases 
        printf("%c",tokholder[0]);
        if (tokholder[0]=='"'){
        char *temp = malloc(sizeof(tokholder)); /// to hold the value of tolk
        strcpy(temp,tokholder);
        tokholder = strsep(&lineholder, ", \n"); // gets next part of quoted comma seperated area
        int lengtht = strlen(tokholder);
        //checks for end quote loops untill it gets end quote in string
        while(tokholder[lengtht-1]!='"'){
        strncat(temp,tokholder,lengtht);
        tokholder = strsep(&lineholder, ", \n");
        }//end while 
        printf("outof special while");
        strcpy(ptrtemp->movie_title, temp);
        free(temp);
        }//end if

我坚持尝试这个？我必须在c

中写这个

Answer 1

有些问题可能是使用sizeof(tokholder)产生指针的大小而不是字符串中的字符数。而是使用strlen ( tokholder)始终添加一个用于终止'\0'。在这种情况下，添加两个以允许将逗号或引号添加回字符串以及终止'\0'。重新分配内存以允许内存，以便可以连接令牌。

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

int main ( void) {
    char line[] = "\"run,fly,jump\",walk,sprint,leap";
    char *lineholder = line;
    char *tokholder = NULL;

    tokholder = strsep(&lineholder, ", \n");//gets next token of the line

    if ( tokholder) {
        //to handle special cases
        if ( tokholder[0] == '\"'){
            char *temp = malloc ( strlen ( tokholder) + 2); // +2 for comma and '\0'
            strcpy ( temp, tokholder);
            strcat ( temp, ",");
            //checks for end quote
            if ( ( tokholder = strsep ( &lineholder, "\""))) {
                int len = strlen ( temp) + strlen ( tokholder) + 2;//+2 for " and '\0'
                char *cap = NULL;
                if ( NULL == ( cap = realloc ( temp, len))) {
                    printf ( "problem realloc\n");
                    free ( temp);
                    return 0;
                }
                temp = cap;
                strcat ( temp, tokholder);
                strcat ( temp, "\"");//add the quote back
            }//end while
            if ( temp) {
                printf ( "temp is %s\n", temp);
                free ( temp);
            }
            if ( lineholder) {
                printf ( "lineholder is %s\n", lineholder);
            }
        }//end if
    }//end if
    return 0;
}

尝试使用逗号

1 个答案: