Recently, I needed to find and replace all instances of “http://website” in the wp_comments table of the WordPress database. Fortunately, SQL provides a simple way to find and replace data with its wonderful UPDATE function. Continue reading »
Recently, after researching comment links for an upcoming article, I realized that my default <input /> values were being submitted as the URL for all comments left without associated website information. During the most recent site redesign, I made the mistake of doing this in comments.php: … <input class="input" name="url" id="url" value="[website]" onfocus="this.select();" type="text" tabindex="3" size="44" maxlength="133" alt="website" /> … Notice the value="[website]" attribute? It seemed like a good idea at the time — I even threw in a nice […] Continue reading »
Not the most interesting title, but “oh well”.. Recently, a reader named Alison left a comment requesting help with a particular htaccess trick. She wanted to know how to permanently redirect (301) all requests for a specific page when requested from a specific IP address. In other words, when a visitor coming from 123.456.789 requests the page requested-page.html, the visitor will be redirected to just-for-you.html. All visitors not coming from that specific IP address are not redirected, and thus will […] Continue reading »
Clean, easy, effective. You don’t need no stinking JavaScript to preload your images. Nope. Try some tasty CSS and (X)HTML instead! Here’s how to do it with only two easy steps.. Step 1 — Place this in your CSS file: div#preloaded-images { position: absolute; overflow: hidden; left: -9999px; top: -9999px; height: 1px; width: 1px; } Step 2 — Place this at the bottom of your (X)HTML document: <div id="preloaded-images"> <img src="https://perishablepress.com/image-01.png" width="1" height="1" alt="" /> <img src="https://perishablepress.com/image-02.png" width="1" height="1" alt="" […] Continue reading »
If you think you understand the logic behind Microsoft’s downlevel conditional comments, you are sadly mistaken. Sure, they seem simple enough on the surface, but as you really try to wrap your head around how and why they work, the subtle complexities of downlevel conditional comments may leave you dazed and confused… In our previous article on Internet Explorer’s exclusive browser-detection method, downlevel conditional comments (DCC), we present an introductory exposition, defining expressions and providing several generalized code examples. Overall, […] Continue reading »
For those of us running Apache, htaccess rewrite rules provide an excellent way to block spammers, scrapers, and other scumbags easily and effectively. While there are many htaccess tricks involving blocking domains, preventing access, and redirecting traffic, Apache’s mod_rewrite module enables us to target bad agents by testing the user-agent string against a predefined blacklist of unwanted visitors. Any matches are immediately and quietly denied access. Continue reading »
On Unix systems, a symbolic link refers to a file that points to another file or directory. Symbolic links serve as powerful tools for web designers and developers. Using shell access, creating a symbolic link requires only one line of code: ln -s /home/username/public_html/directory1 /home/username/public_html/directory2 Simple enough. Assuming you have access to the linux shell. Unfortunately, many shared hosting environments deny shell access. Fortunately, creating symbolic links — also called “symlinks” — remains a possibility via the PHP symlink() function. […] Continue reading »
After studying Peter Kent’s excellent book, Search Engine Optimization for Dummies, several key methods emerged for optimizing websites for the search engines. Although the book is written for people who are new to the world of search engine optimization (SEO), many of the principles presented throughout the book remain important, fundamental practices even for the most advanced SEO-wizards. This article divulges these very useful SEO practices and organizes them into manageable chunks. Continue reading »
This quick tutorial explains how to use HTML, JavaScript, and/or PHP to enable visitors to “go back” to the previous page. You can use either method to add a simple “go back” link or form button to your web pages. Continue reading »
Here is a collection of code snippets for embedding Flash and video using the HTML <object></object> tag. Useful for sites showcasing dynamic multimedia content. Continue reading »
Behold the seventh wonder of the virtual world: max/min-height and max/min-width properties are possible in Internet Explorer! Indeed, by taking advantage of IE’s proprietary CSS attribute, expression, you too can whip IE widths and heights into desirable proportions. The CSS expression attribute enables JavaScript commands to be executed within Internet Explorer. JavaScript via CSS? Thanks, Microsoft! Continue reading »
In our previous article on creating spamless email links via JavaScript, the presented method, although relatively simple to implement, is not the most effective solution available. Spambots, email harvesters, and other online scumbags relentlessly advance their scanning technology, perpetually rendering obsolete yesterday’s methods. Continue reading »
Hiding and filtering CSS rules for specifically targeted browsers is often a foregone conclusion when it comes to cross-browser design considerations. Rather than dive into some lengthy dialogue concerning the myriad situations and implications of such design hackery, our current scheduling restraints behoove us to simply cut to the chase and dish the goods. Having said that, we now consider this post a perpetually evolving repository of CSS filters.. Continue reading »
By using an <iframe></iframe> within a <div></div>, it is possible to include external web content in most any web document. This method serves as an excellent alternative to actual frames, which are not as flexible and definitely not as popular. Indeed, with CSS, the placement, sizing, and styling of div’s provides endless possibilities for embedding external or even internal web content into pages that would otherwise require the use of frames, Flash, or JavaScript. This method works on any modern […] Continue reading »
After digging through the WordPress source code, I stumbled upon this very useful JavaScript method for auto-focusing form elements upon page load. Here is the JavaScript code (place within the document head): Continue reading »
Roll your own Apache Rewrite log! Rocking your own rewrite log is super-helpful for testing .htaccess rewrite rules, WordPress Permalinks, and much more. All you need is Apache 2.2 (or previous), mod_rewrite enabled (very common on most servers), and access to your server configuration file, http.conf. Continue reading »