PHP逐行对变量执行操作

I have a variable containing an html code and I want to perform an action of every line of the code:

<?php

$html = file_get_contents('http://www.google.com/');

#how i would like it to be (not real commands)
/*
$line = 1
$currentline = readline($html,$line)
line++
where $html is the variable that we want to read a line from
$line is the line number
and $currentline the contents

so if $line is 1 we get that $currentline is <html> or whatever

after that i perform things on that line and continue reading each line untill i read all the lines

*/

?>

I hope you understand what I mean/need. I’m very new to web based programming so I need a lot of explanation!

Please don’t use technical terms you think a PHP programmer should know because i do probably don't know what that is.

Your question is similar to this one although one might argue about whether the answers are understandable for a beginner. This should do what you're looking for:

<?php

$html = file_get_contents('http://www.google.com/');
// Skipped: Error checks

// Split $html into lines
$lines = explode("
", $html);

// Iterate over all lines
foreach($lines as $line) {
  // Process $line
}

// Or get the 5th line
$fifth_line = $lines[4];

// Or iterate using an index
for($line = 0; $line < count($lines); $line++) {
  $theline = $lines[$line];
}