PHP regular expression matching to view the source image. how can this problem be solved?

PHP regular expression matching to check which expert of the source image helps to write a regular expression matching content: $ str = 'content & lt; br & nbsp;/& gt; content & lt; img & nbsp; src = "http: www.wz.com/1.jpg" & nbsp; style = "width: 110px" & nbsp; h PHP regular match View Source image
Which of the following experts can help write a regular expression match:
$ Str = 'content Content content Content ';
Matching effect:
$ Str = 'content Content content source image content source Image ';
------ Solution --------------------

$ Str = 'content

 Content content Content ';

Echo preg_replace ('// is', '$0 Source Image', $ str );

Content Content content original image