Is key exists in JavaScript object 

If its necessary to define is item with any key exists in the JavaScript object …

  How can I count a JavaScript object’s attributes? 

To count how many attributes is in the JavaScript object we can use next code:

  Emmet using demonstration 

Basics of emmet …

  Build URL query in WordPress based on an associative array 

Creating URL using PHP associative array …

  Use RegEx to extract URLs from arbitrary content 

Extracting all links from text content …

  Disable xml-rpc in WordPress 

Disabling the XML-RPC API on a WordPress site running 3.5 or above. …

  .htaccess 301 redirect 

If you changed a post permalink and you want to let old one works fine, in your WordPress site .htaccess file add next line:

Where ‘/about’ is old relative URL and ‘http://example.com/about-me’ new URL  

  Create array containing variables and their values 

If its necessary pass to the function a lot of variables – its possible compact them into associative array by next function …

  Memory and time limits for wordpress 

Using next code in wp-config.php file is possible to allow WordPress use more memory for its processes and increase the process performance time: