Escaped & Encapsulated Split/Explode

[blacktiger]

I want to split a string up by the space character (" ") but I want the splitter to ignore the character as a splitting character if it either escaped, or encapsulated in quotes (" "). I did manage to work around the space issue, but slowed down the script a lot more than i would have liked it to do.

Before ran through the string and searched for quotes. And then stored a variable wether or not the string was in quotes. If it was, i would then replace all " "s with Chr(27) [escape]. I later replaced all of the Chr(27)s with spaces after the split. But the additional scanning and replacing process slowed it down too much. If there was any way i could simply make split ignore certain things. I may soon begin working on making my own split function that allows for these things, but i'm just posting to request if there is an easier way.

[blacktiger]

function limited_explode($pattern,$string)
{
  // NOTICE! lilmited_explode's $patter paramter can only be a single character string

  // $instring
  // 0 - No String
  // 1 - Single Quoted String
  // 2 - Double Quoted String
  $instring = 0;

  $prevchar = "";
  $char = "";
  $splitresult = Array();
  $stringlen = strlen($string);
  $lastsplit = 0;

  for($i=0;$i <= $stringlen; $i++)
  {
    $char = substr($string,$i,1);
    if ($char == '"' and $prevchar != "\\")
    {
      if ($instring == 0) // The Beginning Quote. Begin the String
      {
        $instring = 2;
      }
      else if ($instring == 2)  // The End Quote. End the string
      {
        $instring = 0;
      }
    }

if ($char == "'" and $prevchar != "\\")
{
  if ($instring == 0) // The Beginning Quote. Begin the String
  {
    $instring = 1;
  }
  else if ($instring == 1)  // The End Quote. End the string
  {
    $instring = 0;
  }
}

// If we arn't in a string, then check and split the string
if ($char == $pattern and $instring == 0)  // $pattern can only be a single character
{
  $splitted = substr($string,$lastsplit,$i - $lastsplit);
  array_push($splitresult,$splitted);
  $lastsplit = $i+1;
}
$prevchar = $char;
  }// End of for loop

  // Now, throw the last part of the string into the last field of the array
  $splitted = substr($string,$lastsplit,$i - $lastsplit);
  array_push($splitresult,$splitted);
//  echo("(" . $i . "-" . $splitted . ")");

  return $splitresult;
}// End of function

[altexis]

here is a very simplistic idea... don't know if there can be something really more efficient..

// this is your source text
$sourceStr = "....";

// make a list with the sequences you want to leave untouched
$untouched = array('\"', '" "');

// for each element in your untouched list find a replacement that doen't exist in your text
$untouched_replacements = array();
for ($untouched_index=0; ; $untouched_index++) {
  $replacement = "";
  for($i=0;;$i++) if (strpos($sourceStr, "R$i")===false) {
    $replacement = "R$i";
    $untouched_replacements[] = $replacement;
    break;
  }

  // replace the untouched sequences with the safe ones
  $sourceStr = str_replace($untouched[$untouched_index], $replacement, $sourceStr);
}

// now split your string
$result = explode(" ", $sourceStr);

// replace back your untouched sequences
for($row; $row<count($result); $row++)
  for($i; $i<count($untouched); $i++)
    $result[$row] = str_replace($untouched_replacements[$i], $untouched[$i], $result[$row]);

sorry if I missed something... its 2AM here 🙂

try this and tell me if it is any faster .. just out of curiosity 🙂