Sharaz Shahid

Code Widget is simple widget allows you to insert any arbitrary Text/HTML and run PHP Code or Short Code. This Widget parses PHP code into simple text and much more.
Only users with the unfiltered_html role will be allowed to insert unfiltered HTML. This includes PHP code, so users without admin or editor permissions will not be able to use this to execute code, even if they have widget editing permissions. 
This plugin is developed and maintained by <a href="https://twitter.com/sharazghouri1" rel="nofollow ugc">Sharaz Shahid</a>

Code Widget

Code widget help  to  add  Short Code, PHP Code, HTML, and Simple Text in widget.

digitalpoint

The Shortcode Callback plugin allows you to use a [callback] shortcode to execute arbitrary PHP code wherever the shortcode is used.
Usage
Execute someFunction() and insert whatever it returns with the following shortcode: 
 [callback function=”someFunction”]
Example shortcode to include a PHP file (the path is relative to WordPress’ ABSPATH), then insert the results of someFunction() where you used the shortcode: 
 [callback include=”custom/filetoinclude.php” function=”someFunction”]
Shortcode example that includes a PHP file (the path is relative to WordPress’ ABSPATH), then passes a paramter to someFunction() and returns the results where you used the shortcode: 
 [callback function=”someFunction” include=”custom/filetoinclude.php” param=”something”]
The format to call a class/method with the shortcode is exactly the same as above, except you specify the class::method in the “function” attribute of the shortcode. 
 [callback function=”someClass::someFunction” include=”custom/filetoinclude.php” param=”something”]
There is an example (with PHP code) <a href="https://wordpress.org/plugins/shortcode-callback/faq/" rel="ugc">over here</a>.

Shortcode Callback

Adds a [callback] shortcode that can trigger PHP code so you can insert custom/complex things into your pages/posts.

Code Widget vs Shortcode Callback