更改数据库值

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            <div class="grid--cell mb0 mt8">Closed <span title="2012-12-17 17:11:47Z" class="relativetime">7 years ago</span>.</div>
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I want to change some value in my database, pressing on picture on my page, using javascript and AJAX. How can I do it?

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you can use xmlhttprequest, and the javascript :

var xhr = new XMLHttpRequest(); // Create new XHR
var url = 'http://sample.com/change.php'; // The url
var data = 'data=sample&back=come';
xhr.open('POST', url, true); // POST is method you can with `POST|GET`
xhr.send(data);

or it can be simplifer with jquery

var url = 'http://sample.com/change.php'; // The url
var data = 'data=sample&back=come';
$.post(url,data,function(callback){
  alert(callback);
});

and sure bind it on your image:

$("img").click(function(){
    var url = 'http://sample.com/change.php'; // The url
    var data = 'data=sample&back=come';
    $.post(url,data,function(callback){
     alert(callback);
    });
});

then the php file:

<?php
$post_data = mysql_real_escape_string($_POST['data']);
$post_back = mysql_real_escape_string($_POST['back']);
$query = mysql_query("UPDATE table SET data = '".$post_data."' WHERE `back` = '".$post_back."'"); // This is a query, change it with yours
if($query){echo'Success';} //Print a success message
?>

Finish, good luck