检查字符串中的img src关键字

Question

I have a blog system where user inputs the image url in the post content like

hey how are you <img src="example.com/image.png"> 

if the user has written like this

hello how are you <img src="example.com/image.png">

Then I want to find this img src line and use it as featured image

here is what I have tried:

$haystack = 'how are you <img src="hey.png">';

$needle = '<img src="';

if (strpos($haystack, $needle) !== false) {

    echo "$needle";

}
else { echo "no"; }

When I echo I only get:

 <img src="

I want to get whole

<img src="hey.png"> 

from that string how can I do this.

Answer 1

This should work for you:

$string = 'hey how are you <img src="example.com/image.png"> test test <img src="example.com/image2.png">';
preg_match_all('/(<img .*?>)/', $string, $img_tag);
print_r($img_tag[1]);

Output:

Array
(
    [0] => <img src="example.com/image.png">
    [1] => <img src="example.com/image2.png">
)

You should consider using a parser for this though. They have a lot more functionality already built in than a regex, and will error cleaner.

Regex101: https://regex101.com/r/iY1wX0/1

or if you really only over want the first img just use preg_match.

<?php
$string = 'hey how are you <img src="example.com/image.png"> test test <img src="example.com/image2.png">';
preg_match('/(<img .*?>)/', $string, $img_tag);
echo $img_tag[1];

Output:

<img src="example.com/image.png">