Send JS variable to PHP on-click

Question

I have this JS function and I'm looking for the simplest way to send a variable to php and have php return an array to my JS. I have the second part down I just need help sending the variable. Here's my function:

 function myEvent(){
        //console.log(uploaded);
            var length = uploaded.length;
            var content = document.getElementById("Profile");
            if(length == 0){
                content.innerHTML = '<p style="text-align:center"><b> You uploaded no events. </b></p>';

            }
             else {
                content.innerHTML = " ";
            for(var i=0; i<length;i++){
                var entry = document.createElement('li');
                var EID = uploaded[i][0];
                entry.innerHTML= '<a href="eventList2.html">'+uploaded[i][1]+'</a>​';
                content.appendChild(entry); 
                }
                return false;
            }
    }

I want to be able to send EID which is a unique ID to a PHP script every time I click the link.

Any help? I'm using Jquery but I'm not too familiar with it. If there's an option using JS alone I would really appreciate it.

Answer 1

You can do that using Ajax. There's also another really simple way to send data to a php script on any server (same domain or not) while making that php script interact with your page

first you create a script tag:

var tag = document.createElement('script');

the src of that tag will be the url of the php script that will receive the variable:

var myVar = 'foo';
tag.src = '/path/to/my/script.php?variable='+myVar;

you add the script tag to the dom to request it

document.getElementsByTagName('head')[0].appendChild(tag);

on the server side the php script receives the variable and does whatever it should do with it, and optionally it can echo any javascript that will run on the page afterwards:

<?php
echo "alert('".$_GET['variable']."')";

that's pretty much it, WARNING, be aware that this is just a simple example, to implement something like this on a production site you need to make sure that doing so won't open your site to XSS attacks, code injection etc... how to do that is beyond what is being discussed here but be aware