我使用PHP从MySQL数据库中提取值，并尝试使用Highcharts绘制它们。我发现的问题是xaxis值似乎已经过了4个小时。搜索过去的线程，有些人将useUTC：false放在全局图表选项中，但它似乎对我不起作用。
global:{
useUTC: false
}
以下是我用来设置图表的代码。我是一个javascript新手，所以我很可能在这里做了一些愚蠢的事。有什么建议？
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Temperature Data from XBee</title>
<script src="js/jquery-1.11.1.min.js"></script>
<script type="text/javascript">
$(document).ready(function() {
var options = {
chart: {
renderTo: 'container',
type: 'line',
marginRight: 130,
marginBottom: 25
},
title: {
text: 'Wireless Sensor Data: Temperature (F)',
x: -20 //center
},
global: {
useUTC: false
},
yAxis: {
title: {
text: 'temperature'
},
type: 'double',
min: 0,
},
xAxis: {
title: {
text: 'time'
},
type: 'datetime'
},
series: [{
name: 'Temperature',
data: []
}]
}
$.getJSON("data.php", function(json) {
options.series[0].data = json;
chart = new Highcharts.Chart(options);
});
});
</script>
<script src="js/highcharts.js"></script>
<script src="js/themes/grid-light.js"></script>
</head>
<body>
<div id="container" style="min-width: 800px; height: 800px; margin: 0 auto"></div>
</body>
</html>
这是我的PHP代码，用于查询数据库并将数据放入JSON格式。
<?php
$con = mysql_connect("localhost","root","raspberry");
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db("xbee", $con);
$result = mysql_query("SELECT time, temperature FROM data WHERE time >= DATE_SUB(NOW(), INTERVAL 1 HOUR)");
$rows = array();
while($r = mysql_fetch_array($result)) {
extract($r);
$time = strtotime($r[0]);
$time *=1000;
$row[0] = $time;
$row[1] = $r[1];
array_push($rows,$row);
}
print json_encode($rows, JSON_NUMERIC_CHECK);
mysql_close($con);
?>
这就是我的JSON格式。
[[1414172722000,73.4],[1414172727000,73.4],[1414172732000,73.4],[1414172737000,75.2],[1414172742000,75.2],[1414172747000,75.2],[1414172753000,73.4],[1414172758000,75.2],[1414172763000,73.4],[1414172768000,75.2],[1414172773000,75.2],[1414172778000,75.2],[1414172783000,75.2],[1414172788000,73.4],[1414172793000,73.4],[1414172798000,75.2],[1414172803000,75.2],[1414172809000,75.2],[1414172814000,75.2],[1414172819000,75.2],[1414172824000,73.4],[1414172829000,75.2],[1414172834000,75.2],[1414172839000,75.2],[1414172844000,75.2],[1414172849000,75.2],[1414172854000,75.2],[1414172860000,75.2],[1414172865000,75.2],[1414172870000,75.2],[1414172875000,75.2],[1414172880000,75.2],[1414172885000,75.2],[1414172890000,75.2],[1414172895000,75.2],[1414172900000,75.2],[1414172905000,73.4],[1414172910000,75.2],[1414172916000,75.2],[1414172921000,75.2],[1414172926000,75.2],[1414172931000,75.2],[1414172936000,75.2],[1414172941000,75.2],[1414172946000,75.2],[1414172951000,75.2],[1414172956000,75.2],[1414172961000,75.2],[1414172966000,73.4],[1414172972000,75.2],[1414172977000,75.2],[1414172982000,73.4],[1414172987000,75.2],[1414172992000,75.2],[1414172997000,73.4],[1414173002000,75.2],[1414173007000,75.2],[1414173012000,75.2],[1414173017000,75.2],[1414173022000,75.2],[1414173028000,75.2],[1414173033000,75.2],[1414173038000,75.2],[1414173043000,75.2],[1414173048000,75.2],[1414173053000,75.2],[1414173058000,75.2],[1414173063000,71.6],[1414173068000,75.2],[1414173073000,75.2],[1414173079000,75.2],[1414173084000,75.2],[1414173089000,75.2],[1414173094000,75.2],[1414173099000,75.2],[1414173104000,75.2],[1414173109000,75.2],[1414173114000,75.2],[1414173119000,75.2],[1414173124000,75.2],[1414173129000,75.2],[1414173135000,75.2],[1414173140000,75.2],[1414173145000,75.2],[1414173150000,75.2],[1414173155000,75.2],[1414173160000,75.2],[1414173165000,75.2],[1414173170000,75.2],[1414173175000,75.2],[1414173180000,75.2],[1414173185000,75.2],[1414173191000,75.2],[1414173196000,75.2],[1414173201000,75.2],[1414173206000,75.2],[1414173211000,75.2],[1414173216000,75.2],[1414173221000,75.2],[1414173226000,75.2],[1414173231000,75.2],[1414173236000,75.2],[1414173241000,75.2],[1414173247000,75.2],[1414173252000,75.2],[1414173257000,75.2],[1414173262000,75.2],[1414173267000,75.2],[1414173272000,75.2],[1414173277000,75.2],[1414173282000,75.2],[1414173287000,75.2],[1414173292000,75.2],[1414173298000,75.2],[1414173303000,75.2],[1414173308000,75.2],[1414173313000,75.2],[1414173318000,75.2],[1414173323000,75.2],[1414173328000,75.2],[1414173333000,75.2],[1414173338000,75.2],[1414173343000,75.2],[1414173348000,75.2],[1414173354000,75.2],[1414173359000,75.2],[1414173364000,75.2],[1414173369000,75.2],[1414173374000,75.2],[1414173379000,75.2],[1414173384000,75.2],[1414173389000,75.2],[1414173394000,75.2],[1414173399000,75.2],[1414173404000,75.2],[1414173410000,75.2],[1414173415000,75.2],[1414173420000,75.2],[1414173425000,75.2],[1414173430000,75.2],[1414173435000,75.2],[1414173440000,75.2],[1414173445000,75.2],[1414173450000,75.2],[1414173455000,73.4],[1414173461000,75.2],[1414173466000,75.2],[1414173471000,75.2],[1414173476000,75.2],[1414173481000,75.2],[1414173486000,75.2],[1414173491000,75.2],[1414173496000,75.2],[1414173501000,73.4],[1414173506000,75.2],[1414173511000,75.2],[1414173517000,73.4],[1414173522000,75.2],[1414173527000,75.2],[1414173532000,75.2],[1414173537000,75.2],[1414173542000,75.2],[1414173547000,75.2],[1414173552000,73.4],[1414173557000,75.2],[1414173562000,75.2],[1414173567000,75.2],[1414173573000,75.2],[1414173578000,75.2],[1414173583000,75.2],[1414173590000,32],[1414173651000,75.2],[1414173711000,75.2],[1414173771000,73.4],[1414173831000,75.2],[1414173891000,73.4],[1414173951000,75.2],[1414174011000,73.4],[1414174071000,75.2],[1414174131000,73.4],[1414174191000,75.2],[1414174251000,71.6],[1414174311000,73.4],[1414174372000,73.4],[1414174432000,73.4],[1414174492000,73.4],[1414174552000,73.4],[1414174612000,73.4],[1414174672000,73.4],[1414174732000,73.4],[1414174792000,73.4],[1414174852000,73.4],[1414174912000,73.4],[1414174972000,73.4],[1414175032000,73.4],[1414175093000,73.4],[1414175153000,73.4],[1414175213000,73.4],[1414175273000,73.4],[1414175333000,73.4],[1414175393000,73.4],[1414175453000,73.4],[1414175513000,73.4],[1414175573000,73.4],[1414175633000,73.4],[1414175693000,73.4],[1414175753000,73.4],[1414175814000,73.4],[1414175874000,73.4],[1414175934000,73.4],[1414175994000,73.4],[1414176054000,73.4],[1414176114000,73.4],[1414176174000,73.4],[1414176234000,75.2],[1414176294000,75.2]]
答案 0 :(得分：0)
我找到了一个解决方案，不确定这是否是最优雅的，但它现在正在产生正确的结果。看起来在PHP中使用strtotime转换时，它使用的是默认的GMT时区。在PHP脚本中，我添加了date_default_time_set（'UTC'）并且它可以工作。希望这将有助于未来的人。
<?php
$con = mysql_connect("localhost","root","raspberry");
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db("xbee", $con);
$result = mysql_query("SELECT time, temperature FROM data WHERE time >= DATE_SUB(NOW(), INTERVAL 1 HOUR)");
$rows = array();
while($r = mysql_fetch_array($result)) {
date_default_timezone_set('UTC');
extract($r);
$time = strtotime($r[0]);
$time *=1000;
$row[0] = $time;
$row[1] = $r[1];
array_push($rows,$row);
}
print json_encode($rows, JSON_NUMERIC_CHECK);
mysql_close($con);
?>