WordPress excerpts are most useful when you need to display a series of posts in a single page. This often occurs in your –
- WordPress blog homepage – your most recent posts.
- Category page – All posts belonging to the selected category.
- Tag page – All the posts containing the selected tag.
- Archive page – All posts published during the selected date.
- Search results page – All posts and pages matching the search query.
You can set the maximum number of posts that are shown in these pages by going to Settings >> Reading and changing the number on the Blog pages show at most option.
When multiple posts are shown, it is easier for your readers to find what they want by only giving them a summary of each post rather than showing them the entire post. You can enable this post summary functionality by using the WordPress the_excerpt command.
Here is an example blog with styled WordPress excerpts.
1. Enable WordPress Excerpts
This is something that may already be supported in your WordPress theme, but if not, you can enable WordPress excerpts by doing the following –
Go into the index.php file of your theme. Find the line that contains the WordPress command
the_content
.
For example, in the ‘default’ theme you have the lines below in the theme index.php file –
<div class="entry"> <?php the_content('Read the rest of this entry »'); ?> </div>
Replace the line
<?php the_content('Read the rest of this entry »'); ?>
with the code below –
<?php if (is_single() || is_page()) the_content('Read the rest of this entry »'); else { the_excerpt(); } ?>
This will style your blog so that it only shows text summaries when there are multiple posts, but shows the entire document for single posts or single pages.
You can further change the length of your post summaries by following these WordPress codex instructions.
2. Add Background Images to Your WordPress Excerpt
You can pretty up your WordPress excerpts by adding in background images to the top, bottom, or side of each excerpt. This is done by adding a background image entry to certain standard WordPress classes.
The exact class names you need to use will be greatly dependent on your current WordPress theme. However, there are certain standards that are adhered to by most themes.
In particular, each post is usually encapsulated in a post class. If that post is an excerpt, it will further be encapsulated within an excerptcontent class.
.excerptcontent { background: url("side_graphic_URL.jpg") top center repeat-y; border: none; } .post { background: url("top_graphic_URL.jpg") 90% 0% no-repeat; border: none; }
Above, we set a side border graphic and a top background graphic for our excerpts. Just add the above styles into the style.css file of your current WordPress theme.
3. Add Thumbnail Images to Your WordPress Excerpt
To add thumbnail images to our WordPress excerpts, we need a function that extracts the first image from our posts. The get_first_image function below was obtained from the WordPress.org support forum.
function get_first_image() { global $post; $first_img = ''; $output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches); $first_img = $matches [1] [0]; return $first_img; }
Just add this function to your theme functions.php file.
Next we need to call this function from our WordPress theme. Add the code below, right above the_excerpt command, in your theme index.php file.
?> <div class="alignright" style="margin:20px;"> <a href="<?php the_permalink() ?>"> <img src="<?php echo get_first_image();?>" width="200" height="200"/> </a> </div> <?php
This adds a right-aligned image to each post excerpt, which we size at 200px by 200px. The code in your index.php file will now look like this –
<div class="entry"> <?php if (is_single() || is_page()) the_content('Read the rest of this entry »'); else { ?> <div class="alignright" style="margin:20px;"> <a href="<?php the_permalink() ?>"> <img src="<?php echo get_first_image();?>" width="200" height="200"/> </a> </div> <?php the_excerpt(); } ?> </div>
4. Resize the Images in Your WordPress Excerpt
However, the results are still not exactly what we want because the aspect ratio of the images are not maintained. This may make some images look stretched or compressed.
Here is a simple function to resize the image and maintain its aspect ratio. Add the code to your theme functions.php file. –
function url_exists($url) { $headers = wp_get_http_headers($url); if (!is_array($headers)) : return FALSE; elseif (isset($headers["content-type"]) && (strpos($headers["content-type"],"image") !== false)) : return TRUE; else : return FALSE; endif; } function resize_image($image, $alt, $newwidth, $newheight) { if (!file_exists($image) && !url_exists($image)) return ''; list($width, $height, $type, $attr) = getimagesize($image); if (!$width || !$height) return ''; if ($newwidth) $newheight = intval($newwidth/$width * $height); else $newwidth = intval($newheight/$height * $width); return '<img src="' . $image . '" width=' . $newwidth . ' height='. $newheight . ' alt=' . $alt . '/>'; }
- $image is the image file or url.
- $alt is the alternate text to use.
- $newWidth and $newHeight are the new width or height you want to resize the image to. Only one of these parameters will be used to resize the image. If $newWidth = 0 then $newHeight will be used to resize the image. Otherwise, $newWidth will be used.
The resize image function will return the HTML string for the input image, at the proper size. If the image cannot be found, a NULL string is returned.
Finally you just need to call this resize_image function from your theme. Replace the previous call to get_first_image in your index.php file with the code below.
?> <div class="alignright" style="margin:20px;"> <a href="<?php the_permalink() ?>"> <?php echo resize_image(get_first_image(), get_the_title(), 200, 0); ?> </a> </div> <?php
Here is what the final index.php file looks like, instead of the original the_content command.
<?php if (is_single() || is_page()) the_content('Read the rest of this entry »'); else { ?> <div class="alignright" style="margin:20px;"> <a href="<?php the_permalink() ?>"> <?php echo resize_image(get_first_image(), get_the_title(), 200, 0); ?> </a> </div> <?php the_excerpt(); } ?>
Daniel M says
Hi thanks for the guide you took time to write, I’d like to know how I can change the height of the excerpt??
ben says
Hi im just trying to figure out how to remove a “read more” button on specific exeprts, only the ones I choose. any ideas? how do i make the read more dissapear on short exepts?
ShibaShake says
You can use the excerpt_more filter –
http://codex.wordpress.org/Template_Tags/the_excerpt#Only_in_version_2.9_and_higher_of_WordPress
Kristo says
Hi, thanks for the nice “Add thumbnail images” function. I found it to be useful.
However, I’m not so sure about necessity of the “resize_image” function. Firstly – it made the page loading much slower, secondly – why not use only the “width” parameter in the image tag (without “height” parameter)?
It resizes images proportionally and doesn’t need any additional functions…
ShibaShake says
Hello Kristo,
I wrote this tutorial some time ago so I don’t remember the exact context. I think it may have to do with browser and theme compatibility. Specifying just one of the parameters, I think, did not work on some of the older browsers or some of the WordPress themes I was experimenting with. In particular, if the img height is pre-specified in CSS, it may not be overridden.
This is my best guess anyway 🙂 For newer installs I would just use the standard WordPress thumbnail feature that shipped with 2.9.
Mark Divers says
I tried the “Add Thumbnail Images to Your WordPress Excerpt” but could not get it to work. I could not find anything in index.php that said
, but I could in the loop.php file. It occurs in a few places in that file. Hee is the sumary page I want to add thumnails to…
http://randdesertmuseum.com/site/category/johannesburg/johannesburg-mills/
Thanks for any help you can give me! I started with the Twenty Ten theme, this may be the problem.
Mark Divers
ShibaShake says
Hello Mark,
Yeah when I wrote this article, the Default theme was still Kubrick, I should update it at some point.
I just visited the page above and saw that you have added thumbnails to it. Glad you found a solution.
Monty says
Hi,
It’s superb, thanx a million!!!
Only problem is that the div exists in the excerpt even if there’s no image. Is it possible to remove that alignleft div, cause it’s giving space before text cuz I’m using margins for it?
thanx
ShibaShake says
Yeah sure just test for the image before rendering the div. Something like this –
Pascal says
Great tutorial. Works fine but at the end of the text I get […] instead of a link and the word “More”. How can I fix that? Thanks a lot.
ShibaShake says
Try hooking into the excerpt_more filter.
http://codex.wordpress.org/Plugin_API/Filter_Reference/excerpt_more
James says
How about styling fonts, paragraphs etc? Excerpt command seems to strip all formatting. I don’t want to use another plugin because I’m already using “Thumbnail for Excerpts” to include a thumbnail.
Is there some shortcode I can use
Thanks
ShibaShake says
If you just want to style the fonts of the excerpt, then CSS is probably the easiest way to go. Just override the font style using CSS in your child theme style.css or functions.php file.
Here is an article on child-themes –
http://www.shibashake.com/wordpress-theme/customize-your-wordpress-blog-with-child-themes
If you want to operate on the original excerpt data, you can just extract the raw information from the database ($post->post_excerpt or $post->post_content) and then process that.
There are also WordPress filters (e.g. the_excerpt or get_the_excerpt) that allow you to insert your own excerpt processing functions.
Matthew says
Is there a way to modify this so that it calls for the thumbnail version of the first image, instead of simply resizing the image?
ShibaShake says
Hi Matthew,
You have very good timing. I just published a thumbnail plugin that does just that. The plugin uses the WordPress 2.9 post thumbnail system.
http://www.shibashake.com/wordpress-theme/shiba-thumbnail-plugin
Let me know if you have more questions.
ShibaShake says
It will work for any size image and it always preserves the image aspect ratio.
If you enter in a width, it will size the image according to the width, if you set the width to 0, it will size the image according to the height.
Chad says
Does the resizing function only work for square images or can I resize an image to width:300px and height:200px