Question

我有一个.txt文件，内容如下：

PersonName colour1 colour2 colour3

例如：

Nick blue green black
Lisa orange yellow green
Mark white blue orange

我的程序：editColour（fileName，colourInTheFile，colourIWant）应该用colourIWant更改colourInTheFile并返回它执行的次数。问题是它开始循环

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

typedef char String[100];

int editColour(String fileName,String current_colour,String new_colour){

    String name,c1,c2,c3;

    int num_s = 0; /*number of occurence*/

    FILE *fp = fopen(fileName,"r");
    /*this is just a test, so i'm tryng to put the fileName content in this one*/
    FILE *ftemp = fopen("/Users/valerio/Desktop/PROGRAMMI/C/Lezione12_esercizio1/Lezione12_esercizio1/file.txt","w+");
    long pos;

    while(!feof(fp)){


        pos = ftell(fp);
        fscanf(fp, "%s %s %s %s\n",name,c1,c2,c3);


        if(strcmp(c1, current_colour)==0){

            fseek(fp,pos,SEEK_SET);
            fprintf(ftemp, "%s %s %s %s\n",name,new_colour,c2,c3);
            num_s++;

        }
        if(strcmp(c2, current_colour)==0){

            fseek(fp,pos,SEEK_SET);
            fprintf(ftemp, "%s %s %s %s\n",name,c1,new_colour,c3);
            num_s++;

        }
        if(strcmp(c3, current_colour)==0){

            fseek(fp,pos,SEEK_SET);
            fprintf(ftemp, "%s %s %s %s\n",name,c1,c2,new_colour);
            num_s++;

        }

        fprintf(ftemp, "%s %s %s %s\n",name,c1,c2,c3);

    }

    fclose(fp);
    fclose(ftemp);
    return num_s;

}

int main(int argc, const char * argv[]) {

    printf("%d\n\n", editColour("/Users/valerio/Desktop/PROGRAMMI/C/Lezione12_esercizio1/Lezione12_esercizio1/social_users copia.txt",
                                    "orange", "poop"));

}

预期：

       Nick blue green black
       Lisa poop yellow green
       Mark white blue poop (in the new file)

实际：

     Nick blue green black
     Lisa poop yellow green
     Lisa orange yellow green
     Lisa poop yellow green
     Lisa orange yellow green
     Lisa poop yellow green
     Lisa orange yellow green
     Lisa poop yellow green
     Lisa orange yellow green
      .
      .  
      .

循环

Answer 1

以下建议的代码：

干净地编译
执行所需的功能
正确检查错误
避免使用错误的语句：while( !feof(fp) )

现在，建议的代码：

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

#define MAX_CHAR 100

int editColour( char fileName[], char current_colour[], char new_colour[] )
{
    char name[ MAX_CHAR ];
    char c1[ MAX_CHAR ];
    char c2[ MAX_CHAR ];
    char c3[ MAX_CHAR ];

    int num_s = 0; /*number of occurence*/

    FILE *fp = fopen(fileName,"r");
    if( !fp )
    {
        perror( "fopen for input file failed" );
        exit( EXIT_FAILURE );
    }

    FILE *ftemp = fopen("/Users/valerio/Desktop/PROGRAMMI/C/Lezione12_esercizio1/Lezione12_esercizio1/file.txt","w");
    if( !ftemp )
    {
        perror( "fopen for output file failed" );
        fclose( fp );
        exit( EXIT_FAILURE );
    }

    while( fscanf( fp, "%99s %99s %99s %99s\n", name, c1, c2, c3 ) == 4 )
    {
        if( !strcmp( c1, current_colour ) )
        {
            fprintf( ftemp, "%s %s %s %s\n", name, new_colour, c2, c3 );
            num_s++;
        }

        if( !strcmp( c2, current_colour ) )
        {
            fprintf( ftemp, "%s %s %s %s\n", name, c1, new_colour, c3 );
            num_s++;
        }

        if( !strcmp( c3, current_colour ) )
        {
            fprintf( ftemp, "%s %s %s %s\n", name, c1, c2, new_colour );
            num_s++;
        }

        else
        {
            fprintf( ftemp, "%s %s %s %s\n", name, c1, c2, c3 );
        }

    }

    fclose(fp);
    fclose(ftemp);
    return num_s;
}


int main( void ) 
{
    printf("%d\n\n", 
        editColour("/Users/valerio/Desktop/PROGRAMMI/C/Lezione12_esercizio1/Lezione12_esercizio1/social_users copia.txt",
           "orange", "poop"));
}

如何修复fprintf循环？

1 个答案: