Question

With jquery, I’m trying to make it so when the user clicks on a button it runs some code on another page and returns a number, which is placed into #result.

This is probably wrong, but am I on the right lines?

$("#button").click(function(){
    $.post("getdata.php?get=a", function(data){
    $('#result').html(data);
    });

Answer 1

You’re very close

http://api.jquery.com/jQuery.post/

Your data is what you send to the server, in other words, get rid of the ?get=a and instead you’d put it like this

$("#button").click(function(){
    $.post("getdata.php",
    {get: a},
    function(data){
        $('#result').html(data);
    });
});

You see, first you put your url, then you put what you’re sending to the server, then you put the callback function. For clearer code, sometimes it’s written like this

$("#button").click(function(){
    $.post(
        url: "getdata.php",
        data: {get: a},
        success: function(data){
            $('#result').html(data);
        });
});

EDIT: for your purposes, here it is on JSfiddle http://jsfiddle.net/U5XHt/ note that the url doesn’t exist though.