how to get exact answer from ajax? - php

Question

I have some ajax requests in my jquery code. and my php server should decide what to do. but I'm beginner in web programming I don't know how to return the exact response .
<script>
$(document).ready(function () {
$('#subButton').click(function () {
var query = "query";
$.ajax({
type: 'POST',
url: 'info.php',
datatype: 'text',
data: {query: query},
complete: function (data) {
alert(data);// it returns the whole php page!
}
})
.done(function (data) {
alert("done");
})
.fail(function () {
alert("Posting failed.");
});
});
});
</script>
and there is my php code
<?php
if ( isset( $_POST[ 'music' ] ) ) {
echo "music";
}
if ( isset( $_POST[ 'query' ] ) ) {
echo "query";
}
if ( isset( $_POST[ 'url' ] ) ) {
echo "url";
}
?>
in this jquery I want just the word "query" not whole page. and also I want to know how to set it in html through some tags.

Answer 1

so we've found out why your php page is returning the whole script. It had a .html extension, not a .php one. Without the php extension the server would just send back the whole lot.
how to put it into a tag? Quite easy.
suppose you have a tag on your page like this (note the id):
<h2 id="main_heading">some heading</h2>
all you need to do is ask jquery to place the response inside it like this.
complete: function (data) {
// select the object with the right ID and change its innerHTML
$('#main_heading').html(data);
}
this will replace the contents of the <h2> with whatever comes back.
update
if youre having trouble, try putting a console.log call in and check it with the browsers javascript console, this should show you whats being sent back from the server.
like this:
complete: function (data) {
console.log(data);
// select the object with the right ID and change its innerHTML
$('#main_heading').html(data);
}