Question

我正在使用PCRE进行一些正则表达式解析，我需要在字符串中搜索特定模式中的单词（假设用逗号分隔的单词串中的所有单词）并将它们放入字符串向量中。

我将如何做到这一点？

Answer 1

抱歉粗略的代码，但我很着急......

  pcre* re;
  const char *error;
  int   erroffset;
  char* subject = txt;
  int   ovector[3];
  int   subject_length = strlen(subject);
  int rc = 0;


  re = pcre_compile(
  "\\w+",              /* the pattern */
  PCRE_CASELESS|PCRE_MULTILINE,                    /* default options */
  &error,               /* for error message */
  &erroffset,           /* for error offset */
  NULL);                /* use default character tables */

  char* pofs = subject;
  while (  rc >= 0  ) {
    rc = pcre_exec(
      re,                   /* the compiled pattern */
      NULL,                 /* no extra data - we didn't study the pattern */
      subject,              /* the subject string */
      subject_length,       /* the length of the subject */
      0,                    /* start at offset 0 in the subject */
      0,                    /* default options */
      ovector,              /* output vector for substring information */
      3);           /* number of elements in the output vector */

    /*
    if (rc < 0) {
      switch(rc) {
        case PCRE_ERROR_NOMATCH: printf("No match\n"); break;

        // Handle other special cases if you like

        default: printf("Matching error %d\n", rc); break;
      }
      pcre_free(re);     // Release memory used for the compiled pattern
      return;
    }
    */

    /* Match succeded */

    if (  rc >= 0  ) {
      pofs += ovector[1];

      char *substring_start = subject + ovector[0];

      // do something with the substring

      int substring_length = ovector[1] - ovector[0];

      subject = pofs;
      subject_length -= ovector[1];
    }
  }

Answer 2


std::string wordstring = "w1, w2, w3";
std::string word;
pcrecpp::StringPiece inp_w(wordstring);
pcrecpp::RE w_re("(\\S+),?\\s*");
std::vector outwords;

while (w_re.FindAndConsume(&inp_w, &word)) {
    outwords.push_back(word);
}

将PCRE正则表达式中的任意数量的单词匹配到字符串中

2 个答案: