如何在javascript的标头上打印变量？

Question

I have the following code that is not working correctly and I need to check what it is happening. 我有以下代码无法正常工作，我需要检查发生了什么。 The problem is that most of the code is done on the html header. 问题在于大多数代码是在html标头上完成的。 How can I print the variables in order to check what's wrong? 如何打印变量以检查出什么问题？

<!DOCTYPE HTML>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title>Highstock Example</title>

    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
    <script type="text/javascript">
$(function() {
$.getJSON('http://localhost/teste04.php', function(data) {

    // split the data set into ohlc and volume
    var ohlc = [],
        volume = [],
        dataLength = data.length;

    for (i = 0; i < dataLength; i++) {
        ohlc.push([
            data[i][0], // the date
            data[i][1], // open
            data[i][2], // high
            data[i][3], // low
            data[i][4] // close
        ]);

        volume.push([
            data[i][0], // the date
            data[i][5] // the volume
        ]);
    }

    // set the allowed units for data grouping
    var groupingUnits = [[
        'week',                         // unit name
        [1]                             // allowed multiples
    ], [
        'month',
        [1, 2, 3, 4, 6]
    ]];

    // create the chart
    chart = new Highcharts.StockChart({
        chart: {
            renderTo: 'container',
            alignTicks: false
        },

        rangeSelector: {
            selected: 1
        },

        title: {
            text: 'AAPL Historical'
        },

        yAxis: [{
            title: {
                text: 'OHLC'
            },
            height: 200,
            lineWidth: 2
        }, {
            title: {
                text: 'Volume'
            },
            top: 300,
            height: 100,
            offset: 0,
            lineWidth: 2
        }],

        series: [{
            type: 'candlestick',
            name: 'AAPL',
            data: ohlc,
            dataGrouping: {
                units: groupingUnits
            }
        }, {
            type: 'column',
            name: 'Volume',
            data: volume,
            yAxis: 1,
            dataGrouping: {
                units: groupingUnits
            }
        }]
    });
});
});
    </script>
</head>
<body>
<script src="js/highstock.js"></script>
<script src="js/modules/exporting.js"></script>

<div id="container" style="height: 500px; min-width: 500px"></div>

</body>
</html>

Edit: I would like to print "datalength" for example. 编辑：例如，我要打印“数据长度”。

Thanks in advance, Luis 预先感谢路易斯

Answer 1

variables inside the anonymous function you pass as parameter callback to $.getJSON only live inside it's scope. 作为参数回调传递给$ .getJSON的匿名函数内的变量仅存在于其作用域内。
You can use something like console.log(dataLength) inside that function and its value at that time will show up in the browser's console. 您可以在该函数中使用类似console.log（dataLength）之类的内容，届时其值将显示在浏览器的控制台中。
You can use a javascript debugger (firebug in firefox, Javascript Console in Chrome), set up a break point on the first line inside that function and execute it step by step to see the values in each variable. 您可以使用JavaScript调试器（firefox中的firebug，Chrome中的Javascript Console），在该函数内的第一行设置一个断点，然后逐步执行该断点以查看每个变量中的值。

Chrome, imho, has the best console and debugger, so just try this: Chrome，恕我直言，拥有最好的控制台和调试器，因此请尝试以下操作：

$.getJSON('http://localhost/teste04.php', function(data) {
    console.log(data);
    // split the data set into ohlc and volume
    var ohlc = [],
    ............

hit F12 on chrome, refresh the page and whatch all the values inside the data object in the console 在chrome上按F12键，刷新页面并在控制台中获取数据对象内的所有值

如何在javascript的标头上打印变量？

问题描述

1 个解决方案

解决方案1
1 已采纳 2012-08-14 16:49:49

如何在javascript的标头上打印变量？

问题描述

1 个解决方案

解决方案1 1 已采纳 2012-08-14 16:49:49

解决方案1
1 已采纳 2012-08-14 16:49:49