Question: I am familiar of how to get ajax to go to a php page an execute a series of things and then return json data. However is it possible to call a specific function which resides in a given page?

Basically what I want is to reduce the number of files in a project. So I can put a lot of common functions in one page and then just call whatever the function that I want at the moment.

Answer: 
**You cannot call a PHP function directly from an AJAX request, but you can do this instead:**

```
<? php 
    function test($data){
        return $data+1;
    }

    if (isset($_POST['callFunc1'])) {
        echo test($_POST['callFunc1']);
    }
?>
<script>
    $.ajax({
        url: 'myFunctions.php',
        type: 'post',
        data: { "callFunc1": "1"},
        success: function(response) { console.log(response); }
    });
</script>

```
As a structure for this kind of purposes, I suggest this:

PHP
---

```
<?php
    if(isset($_POST['action'])){
        if ($_POST['action'] == "function1") { func1(); }
        if ($_POST['action'] == "function2") { func2(); }
        if ($_POST['action'] == "function3") { func3(); }
        if ($_POST['action'] == "function4") { func4(); }
    }

    function func1(){
        //Do something here
        echo 'test';
    }
?>

```

jQuery
------

```
var data = { action: 'function1' };

$.post(ajaxUrl, data, function(response) {
    if(response != "") {
        $('#SomeElement').html(response);
    }else{
        alert('Error, Please try again.');
    }
});

```

As mentioned, you can't call a PHP function directly from an AJAX call.