我想我已经接近完成通过 JSON/AJAX 将 MySQL 数据传递到 Google Charts 的工作了。我能够以正确的格式输出 JSON 字符串,但它没有输出任何 SQL 数据。我到处寻找没有结果的解决方案。有人看到代码中缺少什么吗?
JSON 输出
{"cols":[{"id":"","label":"projid","type":"string"},{"id":"","label":"hours","type":"number"}],"rows":[{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]},{"c":[{"v":""},{"v":0}]}]}
PHP->JSON
<?php
// -----> Query MySQL and parse into JSON below. <------
// write your SQL query here (you may use parameters from $_GET or $_POST if you need them)
require_once ("Includes/session.php");
require_once ("Includes/simplecms-config.php");
require_once ("Includes/connectDB.php");
$recId = null;
$projid = null;
$hours = null;
$recId = $_GET['id'];
$projid = $_GET['projid'];
$hours = $_GET['hours'];
$query = "SELECT projid, hours FROM hours WHERE id = ?";
$statement = $databaseConnection->prepare($query);
$statement->bind_param('d', $recId);
$statement->execute();
$results = $statement->get_result();
$rows = array();
$table = array();
$table['cols'] = array(
array('id' => "",'label' => 'projid', 'type' => 'string'),
array('id' => "",'label' => 'hours', 'type' => 'number')
);
/* Extract the information from $result */
while ($r = $results->fetch_assoc()) {
$temp = array();
// The following line will be used to slice the Pie chart
$temp[] = array('v' => (string) $r['projid']);
// Values of each slice
$temp[] = array('v' => (int) $r['hours']);
$rows[] = array('c' => $temp);
}
$table['rows'] = $rows;
// convert data into JSON format
$jsonTable = json_encode($table);
echo $jsonTable;
?>