Question

我正在尝试从以下文件中提取介于[HOCKEY]和[使用HOCKEY]之间的文本：

sport.txt：

[HOCKEY]
a=10
b=20
c=30
d=45
[done with HOCKEY]
[SOCCER]
a=35
b=99
c=123
d=145
[done with SOCCER]

使用以下代码，我将能够检查该行是否为[HOCKEY]，但我无法记录[HOCKEY]和[HOCKEY完成]之间的第1行和最后一行的位置

#include<stdio.h>
int main()
{
FILE *infile;
char start, end;
char *sport="[]";
char line_buffer[BUFSIZ]; /* BUFSIZ is defined if you include stdio.h */
int line_number,i;
infile = fopen("sport.txt", "r");
printf("Opened file  for reading\n");
line_number = 0;
while (fgets(line_buffer, sizeof(line_buffer), infile)) {
    ++line_number;
    /* note that the newline is in the buffer */
    if (line_buffer=="[HOCKEY]")
    {
    start=line_buffer;
    printf("Found start %s",start);
  }
      if (line_buffer=="[done with HOCKEY]")
    end=line_buffer;

    while(start<end){
    printf("%c",start);
    start++;
    system("PAUSE");
    }
}
return 0;
}

Answer 1

第一行是[HOCKEY]之后的第一行。以及
最后一行是[done with HOCKEY]之前的最后一行。

所以你需要的是逐行读取文件。当您阅读[HOCKEY]时，您正在接近所需的实际数据，并开始阅读并存储下一行的数据。继续此步骤，直到您阅读[done with HOCKEY]并停止。

Answer 2

int count = 0;
char found_it = 0;
char *wordStart = "[HOCKEY]";
char *wordStop = "[done with HOCKEY]";
int charCount = strlen(wordStart);
while((c = getc(fptr)) != EOF){
    if( c == wordStart[count] ){
        count++;

        if(count == charCount){printf("Found [HOCKEY] \n"); found_it = 1; break;}
    }
    else{
        count = 0;
    }
}

if(!found_it){printf("Did not find [HOCKEY] \n"); return 0;}

count = 0; found_it = 0;
charCount = strlen(wordStop);
while((c = getc(fptr)) != EOF){
    printf("%c", c);
    if( c == wordStop[count] ){
        count++;

        if(count == charCount){found_it = 1; break;}
    }
    else{
        count = 0;
    }
}

if(!found_it){printf("Did not find [done with HOCKEY] \n");}
return 0;

Answer 3

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

int main(){
    FILE *infile;
    fpos_t start, end, pre_pos;
    char line_buffer[BUFSIZ]; /* BUFSIZ is defined if you include stdio.h */
    //char line_buffer[128]; // BUFSIZ : I do not know if there is a large enough

    infile = fopen("sport.txt", "r");
    if(infile)
        printf("Opened file  for reading\n");
    else {
        perror("file open");
        return -1;
    }
    fgetpos(infile, &pre_pos);
    end = start = pre_pos;
    while (fgets(line_buffer, sizeof(line_buffer), infile)) {
        if (strcmp(line_buffer, "[HOCKEY]\n")==0){
            fgetpos(infile, &start);
        } else if (strncmp(line_buffer, "[done with HOCKEY]", 18)==0){//18 == strlen("[done with HOCKEY]");
            end=pre_pos;
            break;
        }
        fgetpos(infile, &pre_pos);
    }
    fsetpos(infile, &start);
    while(start<end){
        printf("%c", fgetc(infile));
        fgetpos(infile, &start);
    }
    fclose(infile);
    system("PAUSE");
    return 0;
}

读取文件并在C中的两行特定文本之间提取行

3 个答案: