php - 使用正则表达式拆分数组

Question

我想知道是否可以使用正则表达式截断数组。

特别是我有一个这样的数组:

$array = array("AaBa","AaBb","AaBc","AaCa","AaCb","AaCc","AaDa"...);

我有这个字符串:

$str = "AC";

我想要 $array 的切片，从匹配 /A.C./ 的字符串开始到最后一次出现(在示例中，索引处的“AaCc” 5):

$result = array("AaBa","AaBb","AaBc","AaCa","AaCb","AaCc");

我该怎么做？我想我可以使用 array_slice，但我不知道如何使用 RegEx。

Answer 1

这是 my bid

function split_by_contents($ary, $pattern){
  if (!is_array($ary)) return FALSE; // brief error checking

  // keep track of the last position we had a match, and the current
  // position we're searching
  $last = -1; $c = 0;

  // iterate over the array
  foreach ($ary as $k => $v){
    // check for a pattern match
    if (preg_match($pattern, $v)){
      // we found a match, record it
      $last = $c;
    }
    // increment place holder
    $c++;
  }

  // if we found a match, return up until the last match
  // if we didn't find one, return what was passed in
  return $last != -1 ? array_slice($ary, 0, $last + 1) : $ary;
}

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更新

我的原始答案有一个没有用的 $limit 参数。我最初确实有一个不同的方向，我打算使用解决方案，但决定保持简单。但是，下面是 version that implements that $limit .所以……

function split_by_contents($ary, $pattern, $limit = 0){
  // really simple error checking
  if (!is_array($ary)) return FALSE;

  // track the location of the last match, the index of the
  // element we're on, and how many matches we have found
  $last = -1; $c = 0; $matches = 0;

  // iterate over all items (use foreach to keep key integrity)
  foreach ($ary as $k => $v){

    // text for a pattern match
    if (preg_match($pattern, $v)){

      // record the last position of a match
      $last = $c;

      // if there is a specified limit, capture up until
      // $limit number of matches, then exit the loop
      // and return what we have
      if ($limit > 0 && ++$matches == $limit){
        break;
      }
    }

    // increment position counter
    $c++;
  }