How can I call PHP functions by JavaScript?

Question

I am trying to call a PHP function from an external PHP file into a JavaScript script. My code is different and large, so I am writing a sample code here.

This is my PHP code:

<?php function add($a,$b){   $c=$a+$b;   return $c; } function mult($a,$b){   $c=$a*$b;   return $c; }  function divide($a,$b){   $c=$a/$b;   return $c; } ?> 

This is my JavaScript code:

<script>   var phpadd= add(1,2); //call the php add function   var phpmult= mult(1,2); //call the php mult function   var phpdivide= divide(1,2); //call the php divide function </script> 

So this is what I want to do.

My original PHP file doesn't include these mathematical functions but the idea is same.

If some how it doesn't have a proper solution, then may you please suggest an alternative, but it should call values from external PHP.

Answer 1

Yes, you can do ajax request to server with your data in request parameters, like this (very simple):

Note that the following code uses jQuery

jQuery.ajax({     type: "POST",     url: 'your_functions_address.php',     dataType: 'json',     data: {functionname: 'add', arguments: [1, 2]},      success: function (obj, textstatus) {                   if( !('error' in obj) ) {                       yourVariable = obj.result;                   }                   else {                       console.log(obj.error);                   }             } }); 

and your_functions_address.php like this:

    <?php     header('Content-Type: application/json');      $aResult = array();      if( !isset($_POST['functionname']) ) { $aResult['error'] = 'No function name!'; }      if( !isset($_POST['arguments']) ) { $aResult['error'] = 'No function arguments!'; }      if( !isset($aResult['error']) ) {          switch($_POST['functionname']) {             case 'add':                if( !is_array($_POST['arguments']) || (count($_POST['arguments']) < 2) ) {                    $aResult['error'] = 'Error in arguments!';                }                else {                    $aResult['result'] = add(floatval($_POST['arguments'][0]), floatval($_POST['arguments'][1]));                }                break;              default:                $aResult['error'] = 'Not found function '.$_POST['functionname'].'!';                break;         }      }      echo json_encode($aResult);  ?>