I want testFunction() to call check() that i created in my plugin php when i click My Button. How do i make it work ?

<?php
function createButton()
{
    echo '<button onclick="testFunction()">My Button</button>';
}

function check()
{
    alert("Works");
}

function my_php_function()
{
    echo '<script>
    function testFunction() {
      check();
    }
  </script>';
}
add_action( 'wp_footer', 'my_php_function' );

I want testFunction() to call check() that i created in my plugin php when i click My Button. How do i make it work ?

<?php
function createButton()
{
    echo '<button onclick="testFunction()">My Button</button>';
}

function check()
{
    alert("Works");
}

function my_php_function()
{
    echo '<script>
    function testFunction() {
      check();
    }
  </script>';
}
add_action( 'wp_footer', 'my_php_function' );

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• 1 You're mixing up PHP and JavaScript. check() either needs to be a JavaScript function in a .js file or between <script></script> tags, or if it needs to be a PHP function, you need to use AJAX to run the function on the server. Your code is just sample code so I can't tell what you need. – Jacob Peattie Commented Jun 5, 2020 at 1:19
• check() needs to be a PHP function. So i need to use AJAX, how do i do that ? – Kitiara Commented Jun 5, 2020 at 1:29

2 Answers 2

AJAX is the solution. For more info: https://codex.wordpress/AJAX_in_Plugins#Separate_JavaScript_File

I could not stand by and see that mangled code. Here is what I think you meant to do.

<?php
function createButton()
{
    echo '<button onclick="testFunction()">My Button</button>';
}

function my_php_function()
{
    echo '<script>
    function check()
    {
        alert("Works");
    }
    function testFunction() {
      check();
    }
  </script>';
}
add_action( 'wp_footer', 'my_php_function' );