是的，不要使用正则表达式来解析HTML，而是使用DOM。

我会这样做：

在工具箱中，用于获取节点内部DOM的函数：

// GET INNER HTML OF A NODE
function DOMinnerHTML($element)  
{ 
    $innerHTML = ""; 
    $children = $element->childNodes; 
    foreach ($children as $child) 
    { 
        $tmp_dom = new DOMDocument(); 
        $tmp_dom->appendChild($tmp_dom->importNode($child, true)); 
        $innerHTML.=trim($tmp_dom->saveHTML()); 
    } 
    return $innerHTML; 
} 

function change_destination_links_for_images( $content ) {   
    $dom = new DOMDocument();
    // THIS IS HACK TO LOAD STRING WITH CORRECT ENCODING
    // JUST OUTPUT <--?xml encoding="UTF-8"--> IN HTML SO NO HARM
    $dom->loadHTML( \'<?xml encoding="UTF-8">\' .  $content );

    // GET ALL <a> NODE
    foreach ( $dom->getElementsByTagName(\'a\') as $node ) {
        // GET HREF 
        $link_href = $node->getAttribute( \'href\' );
        // USE INNER OF THIS <a> NODE AS NEW DOC TO EXTRACT IMG
        $dom_node = new DOMDocument();
        $inner = DOMinnerHTML($node);
        $dom_node->loadHTML($inner);
        // CHECK IF IMAGE INSIDE THE LINK
        if ( $dom_node->getElementsByTagName(\'img\') {
           // IF SO REPLACE HREF
           $node->setAttribute(\'href\', get_permalink() );
           // RETURN MODIFIED DOM
           $content = $dom->saveHTML();
        }
    }
// RETURN CONTENT
return $content;
}
// APPLY FILTER
add_filter( \'the_content\', \'change_destination_links_for_images\' );

我终于找到了一个解决方案，我将脚本与删除原始图像链接的脚本相结合：

/**
 * Remove links from images
  */
add_filter( \'the_content\', \'attachment_image_link_remove_filter\' );
function attachment_image_link_remove_filter( $content ) {
    $content =
        preg_replace(array(\'{<a[^>]*><img}\',\'{/></a>}\'), array(\'<img\',\'/>\'), $content);
    return $content;
}


/**
 * Link images to post
 */
function wpguy_linked_image($content){

    $searchfor = \'/(<img[^>]*\\/>)/\';
    $replacewith = \'<a href="\'.get_permalink().\'">$1</a>\';

    if (is_single() === FALSE){
        $content = preg_replace($searchfor, $replacewith, $content, 1);
    }
    return $content;

}

add_filter(\'the_content\', \'wpguy_linked_image\');