怎么读取C中的.csv文件

Question

读取C中的.csv文件I Have a .csv file :lp;imie;nazwisko;ulica;numer;kod;miejscowosc;telefon;email;data_ur1;Jan;Kowalski;ul. Nowa;1a;11-234;Budry;123-123-456;[e-mail];1980.05.132;Jerzy;Nowak;ul. Konopnicka;13a/3;00-900;Lichowice;(55)333-44-55;[e-mail];1990.03.23我需要用C来读这篇文章，我有一些代码，但只用于连接。

Answer 1

一个完整的示例，它将字段保留为原始输入缓冲区中以空结尾的字符串，并通过char指针数组提供对它们的访问。CSV处理器已经确认可以使用“双引号”中的字段，而忽略其中的任何分隔符字符。

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

// adjust BUFFER_SIZE to suit longest line 

#define BUFFER_SIZE 1024 * 1024

#define NUM_FIELDS 10

#define MAXERRS 5

#define RET_OK 0

#define RET_FAIL 1

#define FALSE 0

#define TRUE 1

// char* array will point to fields

char *pFields[NUM_FIELDS];

// field offsets into pFields array:

#define LP          0

#define IMIE        1

#define NAZWISKo    2

#define ULICA       3

#define NUMER       4

#define KOD         5

#define MIEJSCOw    6

#define TELEFON     7

#define EMAIL       8

#define DATA_UR     9

long loadFile(FILE *pFile, long *errcount);

static int  loadValues(char *line, long lineno);

static char delim;

long loadFile(FILE *pFile, long *errcount){

    char sInputBuf [BUFFER_SIZE];

    long lineno = 0L;

    if(pFile == NULL)

        return RET_FAIL;

    while (!feof(pFile)) {

        // load line into static buffer

        if(fgets(sInputBuf, BUFFER_SIZE-1, pFile)==NULL)

            break;

        // skip first line (headers)

        if(++lineno==1)

            continue;

        // jump over empty lines

        if(strlen(sInputBuf)==0)

            continue;

        // set pFields array pointers to null-terminated string fields in sInputBuf

        if(loadValues(sInputBuf,lineno)==RET_FAIL){

           (*errcount)++;

            if(*errcount > MAXERRS)

                break;

        } else {    

            // On return pFields array pointers point to loaded fields ready for load into DB or whatever

            // Fields can be accessed via pFields, e.g.

            printf("lp=%s, imie=%s, data_ur=%s\n", pFields[LP], pFields[IMIE], pFields[DATA_UR]);

        }

    }

    return lineno;

}

static int  loadValues(char *line, long lineno){

    if(line == NULL)

        return RET_FAIL;

    // chop of last char of input if it is a CR or LF (e.g.Windows file loading in Unix env.)

    // can be removed if sure fgets has removed both CR and LF from end of line

    if(*(line + strlen(line)-1) == '\r' || *(line + strlen(line)-1) == '\n')

        *(line + strlen(line)-1) = '\0';

    if(*(line + strlen(line)-1) == '\r' || *(line + strlen(line)-1 )== '\n')

        *(line + strlen(line)-1) = '\0';

    char *cptr = line;

    int fld = 0;

    int inquote = FALSE;

    char ch;

    pFields[fld]=cptr;

    while((ch=*cptr) != '\0' && fld < NUM_FIELDS){

        if(ch == '"') {

            if(! inquote)

                pFields[fld]=cptr+1;

            else {

                *cptr = '\0';               // zero out " and jump over it

            }

            inquote = ! inquote;

        } else if(ch == delim && ! inquote){

            *cptr = '\0';                   // end of field, null terminate it

            pFields[++fld]=cptr+1;

        }

        cptr++;

    }   

    if(fld > NUM_FIELDS-1){

        fprintf(stderr, "Expected field count (%d) exceeded on line %ld\n", NUM_FIELDS, lineno);

        return RET_FAIL;

    } else if (fld < NUM_FIELDS-1){

        fprintf(stderr, "Expected field count (%d) not reached on line %ld\n", NUM_FIELDS, lineno);

        return RET_FAIL;    

    }

    return RET_OK;

}

int main(int argc, char **argv)

{

   FILE *fp;

   long errcount = 0L;

   long lines = 0L;

   if(argc!=3){

       printf("Usage: %s csvfilepath delimiter\n", basename(argv[0]));

       return (RET_FAIL);

   }   

   if((delim=argv[2][0])=='\0'){

       fprintf(stderr,"delimiter must be specified\n");

       return (RET_FAIL);

   }

   fp = fopen(argv[1] , "r");

   if(fp == NULL) {

      fprintf(stderr,"Error opening file: %d\n",errno);

      return(RET_FAIL);

   }

   lines=loadFile(fp,&errcount);

   fclose(fp);

   printf("Processed %ld lines, encountered %ld error(s)\n", lines, errcount);

   if(errcount>0)

        return(RET_FAIL);

    return(RET_OK); 

}