Searching a textfile by user request

Hi all,
Im trying to make a useful search bar for someone who wants to find a php/html term inside a textfile. (only aobut 50k max)

At the moment im using arrays, but some searches I cannot search for.

In my textfile I have things like:-

#------html
Explaination

#------html/forms
Explaination

#------html/forms/button
Explaination


1) I seem to be able to search for forms and button but not html.

and 2) also it shows all the array elements below which I want to hide somehow.


Heres the code:-

<?php
//
// Class for finding a key in a multi-dimensional array
// This is specific to my needs, not general
//
class key_search
{
  var $found = array();

  // Constructor method
  function key_search($search, $array = '', $case = 0)
  {
    // Set up the parameters
    $search = (!is_array($search)) ? array($search) : $search;
    $array = (!is_array($array)) ? array($array) : $array;
    $ereg = ($case) ? 'ereg' : 'eregi';

    //
    // Search through the array keys for a match
    //

    // Loop through keys
    foreach (array_keys($array) as $key)
    {
      // Loop through search targets
      foreach ($search as $target)
      {
        // Return false if an empty string
        if ($target == '')
        {
          return false;
        }

        // If target expression matches the key and the resolved key in array exists
        if ($ereg($target, $key) && $array[$key][0])
        {
          // Put the resolved key in the list
          $this->found[] = $array[$key][0];
        }
      }
    }

    // Loop through values
    foreach ($array as $value)
    {
      // If the value is an array, search in it
      if (is_array($value))
      {
        $this->key_search($search, $value, $case);
      }
    }
  }
}

//
// Class for getting an array of tags from a file
//
class file_tags
{
  var $list = array();
  var $blocks = array();

  // Constructor method
  function file_tags($file, $marker = '', $separator = '/')
  {
    // Get the raw contents of the file
    $contents = file_get_contents($file);

    // Explode the file into pieces using this special marker
    $this->blocks = explode($marker, $contents);

    // Start breaking the blocks down (ignore the first block, just extra)
    for ($i = 1; $i < count($this->blocks); $i++)
    {
      // Explode the tags into an array
      $tags = explode($separator, trim(substr($this->blocks[$i], 0, strpos($this->blocks[$i], "\n"))));

      // Create a string that looks like an array
      $string = '';
      foreach ($tags as $tag)
      {
        $string .= "['$tag']";
      }
      $string .= "[] = $i";

      // Evaluate the string as a keyset and attach to $list
      eval("\$this->list$string;");
    }
  }
}

// Search keywords
$keywords = stripslashes(trim($_POST['search']));

// Search form
echo '<form method="post" >
 Search for an Article: <input type="text" name="search" value="' . $keywords . '">
<input type="submit" name="submit" value="Submit">
</form>';

// Create a new tag list
$file = new file_tags('PHPlibrary1.txt', '#------');

// Search for keywords in the list
$search = new key_search($keywords, $file->list);
?>

<pre>
<?php
//
// Display
//

// Display found matches
print_r($search->found);

// Loop through found matches
foreach ($search->found as $found)
{
  // Extract the tag for this match
  $tag = trim(substr($file->blocks[$found], 0, strpos($file->blocks[$found], "\n")));

  // Display the tag and its blocked content
  echo "\nTag: $tag\n" . strstr($file->blocks[$found], "\n");
  '</a><div style="margin-top:5px;margin-bottom:2em;border:1px black solid;">';
}

// Display the list
print_r($file->list);
?>
</pre>

Code (markup):

 

Take the text file in a variable.
and using preg_match search the keyword if match then display the content.

 

Hey all, it seems to search all the tag words now,
and I forgot to ' // ' two lines near the bottom of my code to remove the array stuff.

So, to search the whole text in the text file would I still use preg_match? I have not used it in code before.
Is there a way to show 5 search matches at a time?