Submit and load with ajax json - php

Question

index.html:
Function drawChart() {
var jsonData = $.ajax({
url: "server.php",
dataType: "json",
async: false
}).responseText;
var obj = jQuery.parseJSON(jsonData);
var data = google.visualization.arrayToDataTable(obj);
var options = {
title: 'Number of visitors / <?php echo $unit; ?>'
};
var chart = new google.visualization.BarChart(
document.getElementById('chart_div'));
chart.draw(data, options);
}
}
server.php:
$SQLString = "SELECT (...)'".$_POST['value']."' (...)
$result = mysql_query($SQLString);
(...)
$data[$i] = array(...)
echo json_encode($data);
So, index.html get data from server.php right?
Can I send some values to server.php which are important to do the query before index.html do the jsonData...etc? How?
Thanks :)

Answer 1

Example of a query parameter:
var jsonData = $.ajax({
url: "server.php?someQuery=" + query,
dataType: "json",
async: false
}).responseText;

Answer 2

You can send using post method via ajax. Here is a JQuery example:
$.ajax({
type: "POST",
url: "some.php",
data: { name: "John", location: "Boston" }
}).done(function( msg ) {
alert( "Data Saved: " + msg );
});
http://api.jquery.com/jQuery.ajax/

Answer 3

you can use a library that will do it automatically for you, using phery http://phery-php-ajax.net, in your case it would be:
the event phery:json will deal with the JSON sent from the server
var remote = phery.remote('data', {'argument': 'you want to send'}, {'target':'server.php'}, false);
remote.bind('phery:json', function(event, obj){
var data = google.visualization.arrayToDataTable(obj);
var options = {
title: 'Number of visitors / <?php echo $unit; ?>'
};
var chart = new google.visualization.BarChart(
document.getElementById('chart_div'));
chart.draw(data, options);
});
remote.phery('remote'); // call the remote AJAX function
in your server.php
function data($data){
$r = new PheryResponse;
// $data['argument'] will have 'you want to send'
$SQLString = "SELECT (...)'".$_POST['value']."' (...)"
$result = mysql_query($SQLString);
(...);
$data[$i] = array(...);
return $r->json($data);
}
Phery::instance()->set(array(
'data' => 'data'
))->process();