Question

我有一个谷歌图表从我的数据库中提取数据，这是我想要的。根据URL中的get请求，它从选定的表中绘制数据。

我希望根据下拉菜单中的选定表格通过ajax更新此图表。我无法突破的部分是通过ajax响应数据。我认为下面的代码是接近的，但我得到了以下错误，我似乎无法摆脱。

getdata.php：22 Uncaught ReferenceError：$ is defineddrawdrawVisualization @ getdata.php：22onchange @ getdata.php：47

我尝试从getdata.php中删除GET请求并对表格进行硬编码，认为这是$ not defined，但是没有解决错误。

工作图代码

<!DOCTYPE>
<html>
<head> 
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<title>
Wind Graph
</title>
<script type="text/javascript" src="http://www.google.com/jsapi"></script>
<script type="text/javascript">
google.load('visualization', '1', {packages: ['corechart']});
</script>
<script type="text/javascript">

function drawVisualization() {

var data = new google.visualization.DataTable();

<?php
require("dbconnect.php");

echo " data.addColumn('string', 'Time');";
echo " data.addColumn('number', 'Wind_Speed');";
echo " data.addColumn('number', 'Wind_Gust');";

$db = mysql_connect($server, $user_name, $password);
mysql_select_db($database);

$sqlQuery = "SELECT * FROM ".$_GET['q']." WHERE Date(Time + INTERVAL 10 HOUR) = Date(UTC_TIMESTAMP() + INTERVAL 10 HOUR)";
$sqlResult = mysql_query($sqlQuery);
while ($row = mysql_fetch_assoc($sqlResult)) {

echo " data.addRow(['{$row['Time']}', {v: {$row['Wind_Speed']}, f: '{$row['Wind_Speed']}' }, {v: {$row['Wind_Gust']}, f: '{$row['Wind_Gust']}' } ]); ";

}

?>

// Create and draw the visualization.
new google.visualization.LineChart(document.getElementById('visualization')).
draw(data, {curveType: "none",
title: "AU0001 Wind Chart",
titleTextStyle: {color: "orange"},
//width: 800, height: 400,
//vAxis: {maxValue: 10},
vAxis: {minValue: 0},
vAxis: {title: 'Wind Speed (Knots)'},
vAxis: {baseline: 0},
vAxis: {gridlines: {count: 10}  },
vAxis: {title: "Wind Speed (Knots)", titleTextStyle: {color: "orange"}},
hAxis: {title: "Time", titleTextStyle: {color: "orange"}},
interpolateNulls: 1
}
);
}

google.setOnLoadCallback(drawVisualization);
</script>
</head>
<body>
<div id="visualization" style="width: 100%; height: 400px;"></div>
</body>
</html>

使用AJAX请求的新代码

<!DOCTYPE>
<html>
<head> 
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<title>
Wind Graph
</title>
<script type="text/javascript" src="http://www.google.com/jsapi"></script>
<script type="text/javascript">
google.load('visualization', '1', {packages: ['corechart']});
</script>
<script type="text/javascript">

function drawVisualization(num) {

var data = new google.visualization.DataTable(TableData);
var TableData = $.ajax({
  url: "getdata.php",
  data: "q="+num,
  dataType:"json",
  async: false
}).responseText;

// Create and draw the visualization.
new google.visualization.LineChart(document.getElementById('visualization')).
draw(data, {curveType: "none",
title: "Wind Chart",
titleTextStyle: {color: "orange"},
//width: 800, height: 400,
//vAxis: {maxValue: 10},
vAxis: {minValue: 0},
vAxis: {title: 'Wind Speed (Knots)'},
vAxis: {baseline: 0},
vAxis: {gridlines: {count: 10}  },
vAxis: {title: "Wind Speed (Knots)", titleTextStyle: {color: "orange"}},
hAxis: {title: "Time", titleTextStyle: {color: "orange"}},
interpolateNulls: 1
}
);
}

//  google.setOnLoadCallback(drawVisualization);
</script>
</head>
<body style="font-family: Arial;border: 0 none;">
<form>
<select name="users" onchange="drawVisualization(this.value)">
<option value="">Select unit:</option>
<option value="0001">0001</option>
<option value="0002">0002</option>

</select>
</form>
<div id="visualization" style="width: 100%; height: 400px;"></div>
</body>
</html>

getdata.php代码

<?php
require("dbconnect.php");

echo " data.addColumn('string', 'Time');";
echo " data.addColumn('number', 'Wind_Speed');";
echo " data.addColumn('number', 'Wind_Gust');";

$db = mysql_connect($server, $user_name, $password);
mysql_select_db($database);


$sqlQuery = "SELECT * FROM ".$_GET['q']." WHERE Date(Time + INTERVAL 10 HOUR) = Date(UTC_TIMESTAMP() + INTERVAL 10 HOUR)";
$sqlResult = mysql_query($sqlQuery);
while ($row = mysql_fetch_assoc($sqlResult)) {

echo " data.addRow(['{$row['Time']}', {v: {$row['Wind_Speed']}, f: '{$row['Wind_Speed']}' }, {v: {$row['Wind_Gust']}, f: '{$row['Wind_Gust']}' } ]); ";

}

?>

通过AJAX请求根据用户输入重绘Google图表

0 个答案: