通过$ .ajax将javascript值传递给PHP

Question

I have a dropdown with different options. When you select one option, the text inside the option, this, is shown below the dropdown menu. I do this with this code:

  var stadsnat_ar = new Array();
    $(".stadsnat_options").change(function() {

            stadsnat_ar.push($(".stadsnat_options option:selected").val()); //This value should be used in PHP to get correct data from MySQL

            var stadsnat = stadsnat = $(".stadsnat_options option:selected").text();    //show the text
            $('#teststat').show().append('<br>' + stadsnat);
    });

The whole idea is that you can choose multiple options, and then hit submit, to do a search in MySQL with the options you choosed. As you can see, I assign a array with the values of the options you choosed. How can I make the values in the array, visible to PHP?

I've tried this:

$.ajax({
    type: "POST",
    url: 'searchengine.php',
    data: {stad_value: stadsnat_ar},
    success: "",
    dataType: "json"
});

Then I do this:

<?php
echo $_POST['stad_value'];
?>

But nothing appears. Anyone?

Answer 1

You don't seem to have any problems exposing the values to PHP, all your problems seem to come after that stage.

1. success needs to be a function that does something with the HTTP response data, not an empty string.
2. If you tell jQuery to ignore what the server says the data is and treat it as JSON, then make sure you send JSON back
3. echoing arrays probably isn't very useful.

e.g.

$.ajax({
    type: "POST",
    url: 'searchengine.php',
    data: {stad_value: stadsnat_ar},
    success: doSomething,
    dataType: "json"
});

function doSomething(data) {
    $('body').text(data.join("-"));
}

and

<?php
header("Content-Type: application/json");
echo json_encode($_POST['stad_value']);
?>