PHP - Big Function, Arrays, Variables...i Want To Speed Things Up.

I would like to be able to use a succession of php preg_match() and preg_replace() functions in one script without having to produce clutter in this match and replace php coding script and without its results showing arrayed forms. The following is a RegExp formula that I'm comfortable with that involves only a replace function. I'm curious what the best way would be to scoot a RegExp match function into a script like this one that is consistent with the same $current .= preg_replace('/a/', 'b', $current); php code that I've shown here et. al. that can be written out on one string. I've seen some php implode()  functions, but my concern is that an additional function as such along with preg_mach() functions will cause a lot of deviation in a list of regular regex match and replace functions. What can I do to keep both php match and replace RegExp functions strings typed out in linear concession for the sake of keeping things organized when strictly relating to regex functions and working with them within php and working something like an implode() function into my php script so that match and replace functions can produced organized results outside of having to make use of arrays?       

<?php
$file = 'sample.txt';
$current = file_get_contents($file);
$current .= preg_replace('/a/', 'b', $current);
file_put_contents($file, $current);
?>

I have a php file with a bunch of variables declared.  I now need a function to put data on a separate page that pulls variables from the required page.

So, on the required page, I have a variable set like this:  $qb1 = "John Doe";

The function on the new script is called like this:  getplayer($qb1);

I've tried this without the dollar sign in the function like this: getplayer(qb1); and then adding the $dollar sign in the rest of the function code...but it never populates the sql query correctly.  I'm guessing this is a case for variable variables or something similar, but I don't know how to get the variable value from the required page.  Any ideas?  Thanks.

Here's the code:

	<?php
	function getplayer($position)
{ // start function
	//$new_position = "$" . $position;
$new_position = $position;
	
$file = "their.php";
require "$file";
//echo $qb1;    this displays the name John Doe...as $qb1 is declared in the required file
	
$db_select_their = "bschultz_their";
	$servername = "localhost";
$username = "user";
$password = "pass";
$dbname = "db_name";
	// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}
	$sql = "SELECT * FROM (select number as position_number, name as position_name, pronunciation as position_pronunciation, pos as position_pos, height as position_height, weight as position_weight, year as position_year, city as position_city, state as position_state, notes as position_notes FROM $db_select_their WHERE name = '$new_position') as position";
	//$sql = "SELECT * FROM bschultz_their WHERE name = $new_position";
   
echo $sql; //exit;        
/*
this displays this text...   SELECT * FROM (select number as position_number, name as position_name, pronunciation as position_pronunciation, pos as position_pos, height as position_height, weight as position_weight, year as position_year, city as  position_city, state as position_state, notes as position_notes FROM bschultz_their WHERE name = '') as position

The name is empty
*/
	$result = $conn->query($sql);
	if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {
        echo "#: " . $position_number . " - Name: " . $position_name . "";
    }
} else {
    echo "0 results";
}
	} // end function
	
getplayer("${$qb1}");
$conn->close();
?>