Keep the first Nr IMG tags, Strip all the others

Php-mysql Course

The keepFirstImgs() function presented in this page can be used in PHP to keep the first Nr IMG tags into a string, and Strip all the other <img>s.
- The function receives the number of the first <img> tags to keep ($nrimg), and the string with the HTML text ($str); returns the string with the other IMG tags removed.

// Function to keep first $nrimg IMG tags in $str, and strip all the other <img>s
// From: https://coursesweb.net/php-mysql/
function keepFirstImgs($nrimg, $str) {
  // gets an array with al <img> tags from $str
  if(preg_match_all('/(\<img[^\>]+\>)/i', $str, $mt)) {
    // gets array with the <img>s that must be stripped ($nrimg+), and removes them
    $remove_img = array_slice($mt[1], $nrimg);
    $str = str_ireplace($remove_img, '', $str);
  }
  return $str;
}

- Example:

<?php
// Function to keep first $nrimg IMG tags in $str, and strip all the other <img>s
// From: https://coursesweb.net/php-mysql/
function keepFirstImgs($nrimg, $str) {
  // gets an array with al <img> tags from $str
  if(preg_match_all('/(\<img[^\>]+\>)/i', $str, $mt)) {
    // gets array with the <img>s that must be stripped ($nrimg+), and removes them
    $remove_img = array_slice($mt[1], $nrimg);
    $str = str_ireplace($remove_img, '', $str);
  }
  return $str;
}

// Test, keeps the first two IMG tags in $str
$str = 'First img: <img src="img1.jpg" alt="img 1" width="30" />,
 second image: <img src="img_2.jpg" alt="img 2" width="30">,
 another Img tag <img src="img3.jpg" alt="img 3" width="30" />,
 and another image <img src="img_5.jpg" alt="imgage 5" width="30" /> ... etc.';
$str = keepFirstImgs(2, $str);
echo $str;
/* Output:
 First img: <img src="img1.jpg" alt="img 1" width="30" />,
 second image: <img src="img_2.jpg" alt="img 2" width="30">,
 another Img tag , and another image  ... etc.
*/
?>

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</object>

input:focus {
  background-color: #88fe88;
}

var jsnstr = '{"url": "http://coursesweb.net/", "title": "Web Development Courses"}';
var obj = JSON.parse(jsnstr);
alert(obj.url);

if (file_put_contents("file.txt", "content")) echo "The file was created";
else echo "The file can not be created";