javascript - google.visualization.DataTable，日期未定义

Question

考虑以下代码:

google.load("visualization", "1", {
    packages: ["corechart"]
});
google.setOnLoadCallback(drawChart);

function drawChart() {
    var data = google.visualization.DataTable();
    data.addColumn('datetime', 'Time');
    data.addColumn('number', 'Leads');
    data.addRow([Date.parse("2013-08-17 10:12:18"), 0]);
    data.addRow([Date.parse("2013-08-17 09:13:42"), 14]);
    data.addRow([Date.parse("2013-08-17 10:00:05"), 15]);
    data.addRow([Date.parse("2013-08-17 11:12:18"), 3]);
    var options = {
        title: 'Company Performance',
        fontSize: '12px',
        curveType: 'function',
        pointSize: 5,
        hAxis: {
            title: 'Daily Report',
            titleTextStyle: {
                color: '#FF0000'
            }
        },
        vAxis: {
            title: 'Leads',
            titleTextStyle: {
                color: '#FF0000'
            }
        }
    };

    var chart = new google.visualization.LineChart(document.getElementById('chart_div'));
    chart.draw(data, options);
}

现在，上面的代码可以加载谷歌图表API，定义一个DataTable并生成一个LineChart图表，但事实并非如此。相反，我在尝试添加列时出现以下错误

TypeError: data is undefined #at this line --> data.addColumn('datetime', 'Time')

谁能告诉我我错过了什么？

Answer 1

您在创建 google.visualization.Datatable 的新对象时没有使用 new。

 function drawChart() {
    // var data = google.visualization.DataTable(); missed new keyword
    var data = new google.visualization.DataTable();
 //...
 }