Regular expression URL (URL) [a-zA-z]+://[^\s]*IP address (IP Address)((2[0-4]\d|25[0-5]|[01]?\d\d?)\.){3}(2[0-4]\d|25[0-5]|[01]?\d\d?) Email (Email)\w+([-+.]\w+)*@\w+([-.]\w+)*…

When the result of division needs to be rounded in PHP, the following methods are needed: 1. round: round () function rounds floating-point numbers. Syntax: round(x, prec) parameter description x is optional. Specifies the number to round. Prec is optional. Specify the number of digits after the decimal point. Description: Returns the number of x based on the specified precision prec (decimal decimal number …

& lt; ? php $a = & quot; & lt; a& gt; The crab society afeowahgieawhjozf waits for the snake fawgwea to maintain stability aghoiawghowi &amp lt; /a& gt; & quot; ; $result = preg_replace(' /([\x80-\xff]*)/i' ,' ' ,$a); var_du…

List the files and directories in the images directory:&; lt; ? php $dir = & quot; /images/& quot; ; $a = scandir($dir); $b = scandir($dir,1); print_r($a); print_r($b); ? & gt; Results: array ([0] =&; gt…

The following are several special symbols used to establish the path and their meanings. "./":represents the current directory. "../":stands for the upper level directory. Start with "/":stands for root directory.

Setting response headers in PHP: 1. Setting the response header for file types: `<?php header('Content-Type: text/css; charset=GBK'); // For CSS files, using GBK encoding; header('Content-Type: text/html; charset=UTF-8'); // For HTML files, using UTF-8 encoding...`

In Typecho’s official theme development documents, there are very few development instructions related to article custom fields and theme settings. I also looked at the code of some open source themes to understand the development of custom fields and theme settings. Here I will briefly write about the definition and invocation of article custom fields and theme settings. Article custom fields After the article custom fields are defined, they will be displayed below the edit box on the article editing interface. Users can use the defined options...

The `str strstr()` function searches for the first occurrence of one string within another string. It returns the remaining part of the string (starting from the matching position); if the target string is not found, it returns `false`. The code is as follows: `<?php $email = 'user@example.com'; $domain = strstr($email,...`

Use browser caching of official words: If users will visit your website multiple times, browser caching of static resources can save users time. Cache headers should be applied to all cacheable static resources, not just to a small subset of static resources (for example, images). Cacheable resources include JS and CSS files, image files, and other binary object files (media files, PDF files, etc.). Normally, HTML doesn’t…

When making templates, you may need to use plug-ins in some places. Then you need to check whether the plug-in is enabled, you can use the following plug-in: <?php $all = Typecho_Plugin::export();?> <?php if (array_key_exists('plugin name', $all['activated'])) : …