问如何将标记与字符串分开？

EN

$string = "red blue Dark Green green Dark Blue";
// preg_split() on one or more whitespace chars
$words = preg_split('/\s+/', $string);
$upwords = "";
// Temporary array to hold output...
$words_out = array();

foreach ($words as $word) {
  // preg_match() ins't the only way to check the first character
  if (!preg_match('/^[A-Z]/', $word)) {
    // If you already have a string built up, add it to the output array
    if (!empty($upwords)) {
      // Trim off trailing whitespace...
      $words_out[] = trim($upwords);
      // Reset the string for later use
      $upwords = "";
    }
    // Add lowercase words to the output array
    $words_out[] = $word;

  }
  else {
    // Build a string of upper-cased words
    // this continues until a lower cased word is found.
    $upwords .= $word . " ";
  }
}
// At the end of the loop, append $upwords if nonempty, since our loop logic doesn't
// really account for this.
if (!empty($upwords)) {
  $words_out[] = trim($upwords);
}

// And make the whole thing a string again
$output = implode(", ", $words_out);

echo $output;
// red, blue, Dark Green, green, Dark Blue

$words = explode(' ',$string);
$tags = '';
$tag = '';
foreach($words as $word)
{
  if(ord($word >=65 and ord($word <=65))
    {
       $tag .= $word.' '; 
    }
  else
   $tags .= $word.',';
}
$tags = trim($tags,',').trim($tag);
print_r($tags);