Title: Fatal Error: Undefined Function in stand alone PHP script
Last modified: August 21, 2016

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# Fatal Error: Undefined Function in stand alone PHP script

 *  [jfvonjr](https://wordpress.org/support/users/jfvonjr/)
 * (@jfvonjr)
 * [11 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-undefined-function-in-stand-alone-php-script/)
 * Hi everyone. I would like to be able to track a user’s preference for sounds 
   on the website. The preference has to be available from page load to page load.
 * I added an option to the funtions.php script
 * `add_option('audio_toggle','on','','yes');`
 * Next, I created a stand alone php script (raven-functions.php) to update or get
   a user defined option.
 *     ```
       <?php
       /** =================================
        *  AUDIO FUNCTIONS
        * ================================== */
   
           	if(isset($_POST['action']) && !empty($_POST['action'])) {
               	$action = $_POST['action'];
               	switch($action) {
               		case 'get_audio_toggle' :
                   			get_audio_toggle();
       		            	break;
               		case 'set_audio_toggle' :
       		            	set_audio_toggle();
                   			break;
               	}
           	}
   
       	function get_audio_toggle() {
       		echo get_option('audio_toggle');
       	}
       	add_action('get_option', 'get_audio_toggle');
   
       	function set_audio_toggle() {
       		if(isset($_POST['new_value']) && !empty($_POST['new_value'])) {
       			$new_value = $_POST['new_value'];
       			update_option('audio_toggle', $new_vlaue);
       			echo get_option('audio_toggle');
       		}
       	}
       	add_action('update_option', 'set_audio_toggle');
       ?>
       ```
   
 * Finally, I created a javascript that would respond to the user clicking a ‘speaker’
   image on or off on the webpage. The function in the javascript calls the both
   PHP functions using AJAX.
 *     ```
       //==========================================================
       //  AUDIO FUNCTIONS
       //==========================================================
       //--------------------------------------
         function toggleAudio() {
       //-------------------------------------- 
   
           $.get("/wordpress/wp-content/themes/LCARS/raven_functions.php", {action:'get_audio_toggle'}, function(response, status) {
               if (status === "success") {
                   var myAudio = document.getElementById("raven-audio");
                   var toggle = "";
                   if(response === "off") {
                       $('#raven-audio-image').css('background','url(/wordpress/wp-content/themes/LCARS/images/raven-audio-on-000.png)');
                       $('#raven-audio-image').prop('title','click to turn audio off');
                       myAudio.play();
                       toggle = "on";
                   }
                   else {
                       $('#raven-audio-image').css('background','url(/wordpress/wp-content/themes/LCARS/images/raven-audio-off-000.png)');
                       $('#raven-audio-image').prop('title','click to turn audio on');
                       myAudio.pause();
                       myAudio.currentTime = 0;
                       toggle = "off";
                   }
                   $.post("/wordpress/wp-content/themes/LCARS/raven_functions.php", {action:'set_audio_toggle', new_value:toggle});
               }
           });
         }
       ```
   
 * When I click the image button on the webpage, I am getting the following error
   message, “fatal error: undefined function update_option() in the php file at 
   line 27. I am new to wordpress and read through documentation and searched for
   a solution. I alsso made sure that the option.php script was included as a required
   in the wp-settings.php file.
 * I would appreciate if someone could help point me in the right direction to resolving
   what should be a simple requirement.
 * Thank you,
    Jim Von Dolteren

Viewing 1 replies (of 1 total)

 *  [stephencottontail](https://wordpress.org/support/users/stephencottontail/)
 * (@stephencottontail)
 * [11 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-undefined-function-in-stand-alone-php-script/#post-5138546)
 * As you’ve discovered, you can’t AJAX directly to an arbitrary PHP file because
   WordPress’ functions won’t get loaded. Instead, you should `$.post` to `ajaxurl`,
   which automatically points to `admin-ajax.php` (despite the name, it works for
   front-end and back-end AJAX requests). Check out [AJAX in Plugins](http://codex.wordpress.org/AJAX_in_Plugins)
   for more information.
 * Also, you’ve got a minor mistake in your PHP: `update_option('audio_toggle', 
   $new_vlaue);` should probably be `update_option('audio_toggle', $new_value);`
   instead.

Viewing 1 replies (of 1 total)

The topic ‘Fatal Error: Undefined Function in stand alone PHP script’ is closed 
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## Tags

 * [javascript](https://wordpress.org/support/topic-tag/javascript/)
 * [undefined function](https://wordpress.org/support/topic-tag/undefined-function/)
 * [update_option](https://wordpress.org/support/topic-tag/update_option/)

 * 1 reply
 * 2 participants
 * Last reply from: [stephencottontail](https://wordpress.org/support/users/stephencottontail/)
 * Last activity: [11 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-undefined-function-in-stand-alone-php-script/#post-5138546)
 * Status: not resolved

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