Eliminate 404 Errors for PHP Functions

Recently, I discussed the suspicious behavior recently observed by the Yahoo! Slurp crawler. As revealed by the site’s closely watched 404-error logs, Yahoo! had been requesting a series of nonexistent resources. Although a majority of the 404 errors were exclusive to the Slurp crawler, there were several instances of requests that were also coming from Google, Live, and even Ask. Initially, these distinct errors were misdiagnosed as existing URLs appended with various JavaScript functions. Here are a few typical examples […] Continue reading »

Bare-Bones HTML/XHTML Document Templates

In this post I have assembled a concise collection of conforming, bare-bones document templates for just about every DOCTYPE for HTML, XHTML, and more. Continue reading »

Rethinking Structural Design with New Elements in HTML 5

HTML 5, also known as Web Applications 1.0, provides new markup elements that will change the way you design your web pages. The new elements replace commonly used divisions in web documents, facilitating an even greater degree of separation between structure (HTML) and presentation (CSS). Indeed, in many documents, the new elements will structure the document while providing enough hooks to render obsolete previously required divisions, classes, and identifiers. Let’s take a look.. Continue reading »

Super Loop: Exclude Specific Categories and Display any Number of Posts

[ Image: Detail view of a series of mechanical gears (black and white photo) ]

Readers occasionally ask for help with their WordPress loops. Usually, these requests involve modifying the loop with some customized functionality. Frequently, such customization involves one of these popular behaviors: Continue reading »

Temporary Site Redirect for Visitors during Site Updates

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In our article Stupid htaccess Tricks, we present the htaccess code required for redirecting visitors temporarily during periods of site maintenance. Although the article provides everything needed to implement the temporary redirect, I think readers would benefit from a more thorough examination of the process — nothing too serious, just enough to get it right. After discussing temporary redirects via htaccess, I’ll also explain how to accomplish the same thing using only a small slice of PHP. It’s like two […] Continue reading »

Essential HTML Entities

Virtually every article written here at Perishable Press requires at least one or two “special” HTML characters. Some of these characters — such as quotation marks, hyphens, and dashes — are very common, while others — such as the copyright symbol, bullet, and arrow — happen less frequently. The vast majority of special characters, however, like the latin Ä (i.e., capital letter “A” with a diaeresis), and the mathematical symbol ⊃ (i.e., superset), rarely see the light of day on […] Continue reading »

MySQL Magic: Find and Replace Data

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 »

Another Mystery Solved..

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 »

CSS Throwdown: Preload Images without JavaScript

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 »

Wrapping Your Head around Downlevel Conditional Comments

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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 »

Use PHP to Create Symbolic Links without Shell Access

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 »

The Friendliest Link Targets in the Neighborhood

The target attribute for anchor elements (<a></a>) specifies the location in which the referenced document should load. For example, to open a link in a new window, we would use a target value of _blank. Although this is a commonly employed technique, the target attribute has been deprecated by the W3C and is not valid (X)HTML. Regardless, the target element remains a useful tool for practicing designers and developers. Here, we present the attribute values for the target element: Continue reading »

Go Back via JavaScript and PHP

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 »

URL Character Codes

URLs frequently employ potentially conflicting characters such as question marks, ampersands, and pound signs. Fortunately, it is possible to encode such characters via their escaped hexadecimal ASCII representations. For example, we would write ? as %3F. Here are a few more URL character codes (case-insensitive), for easy copy/paste reference. Continue reading »

Embed Flash and Video via the object Tag

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 »

Maximum and Minimum Height and Width in Internet Explorer

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 »

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