Variable not working in simple Ajax post

Question

Can't seem to get the variable getID to work. I'm trying to change the html of the div. I know that the variable has the right value.

$('.cardid').change(function() {
    var getID = $(this).attr('value');

        $.ajax({
        type: "POST",
        url: "inc/change_thumbnail.php",
        data: "id="+getID,
        cache: false,
        success: function(data) {
            $("#"+getID).html(data);
            alert("success");
        },
        error: function (err) {
            alert("error"); 
        }
    });

});        

Answer 1

将$ .ajax中的数据作为数据：{id：getID}而不是数据：“ id =” + getID，

Answer 2

Use val to get the value of an input :

var getID = $(this).val();

As you're making a POST request, you should also use the data argument to let jQuery properly send the value :

$.ajax({
    type: "POST",
    url: "inc/change_thumbnail.php",
    data: {id:getID},
    cache: false,
    success: function(data) {
        $("#"+getID).html(data);
        alert("success");
    },
    error: function (err) {
        alert("error"); 
    }
});

Answer 3

You can try this:

$('[id="'+getID+'"]').html(data);

and yes you should pass it this way:

data:{id:getID}