为了获取历史信息，我尝试使用以下代码。 Chrome 调试器提示 Uncaught ReferenceError: $ is not defined。你能建议一个修复方法吗，我真的被困住了。我只需要它在 Chrome 上工作，我正在利用 YQL 和 Yahoo API。
这是 jsFiddle http://jsfiddle.net/pCK5q/1/
<html>
<head>
<script type='text/javascript' src='http://www.google.com/jsapi'></script>
<script type='text/javascript'>
google.load('visualization', '1', {'packages':['annotatedtimeline']});
google.setOnLoadCallback(drawChart);
function drawChart() {
var data = new google.visualization.DataTable();
/* historical data code that breaks */
var url = 'http://query.yahooapis.com/v1/public/yql';
var startDate = '2012-01-01';
var endDate = '2012-01-08';
var jsonData = encodeURIComponent('select * from yahoo.finance.historicaldata where symbol in ("YHOO","AAPL","GOOG","MSFT") and startDate = "' + startDate + '" and endDate = "' + endDate + '"');
$.getJSON(url, 'q=' + data + "&env=http%3A%2F%2Fdatatables.org%2Falltables.env&format=json", callback);
data.addColumn('date', 'Date');
data.addColumn('number', 'Sold Pencils');
data.addColumn('string', 'title1');
data.addColumn('string', 'text1');
data.addColumn('number', 'Sold Pens');
data.addColumn('string', 'title2');
data.addColumn('string', 'text2'); // not on the fly
data.addRows([
[new Date(2008, 1 ,1), 30000, undefined, undefined, 40645, undefined, undefined],
[new Date(2008, 1 ,2), 14045, undefined, undefined, 20374, undefined, undefined],
[new Date(2008, 1 ,3), 55022, undefined, undefined, 50766, undefined, undefined],
[new Date(2008, 1 ,4), 75284, undefined, undefined, 14334, 'Out of Stock','Ran out of stock on pens at 4pm'],
[new Date(2008, 1 ,5), 41476, 'Bought Pens','Bought 200k pens', 66467, undefined, undefined],
[new Date(2008, 1 ,6), 33322, undefined, undefined, 39463, undefined, undefined]
]);
var chart = new google.visualization.AnnotatedTimeLine(document.getElementById('chart_div'));
chart.draw(data, {displayAnnotations: true});
}
</script>
</head>
<body>
// Note how you must specify the size of the container element explicitly!
<div id='chart_div' style='width: 700px; height: 240px;'></div>
</body>
最佳答案
只需在脚本之前添加对 JQuery 源的引用:
<script src="http://code.jquery.com/jquery.min.js"></script>
关于javascript - jQuery 美元符号未定义，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/13482022/