Google图表：“无法读取未定义的属性'toLowerCase'”

Question

I try to generate a google chart. It returns " Cannot read property 'toLowerCase' of undefined " in the chart area but no error in the console.

function drawChart(chart_data, chartType, chartOptions){

           console.log(chartOptions);

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

            var chart = new google.visualization.ChartWrapper({

                chartType: chartType,
                dataTable: data,
                options: chartOptions,
                containerId: 'chart'

            });

            chart.draw();
        }

The results of the console.log is a string that looks like:

{"title":"test","vAxis":{"minValue":"0"},"hAxis":{"showTextEvery":"1"},"chartArea":{"width":"70%","height":"90%"},"pointSize":"7","height":"500","intervals":{"lineWidth":2,"barWidth":0.5,"color":"#000000"}} 

If I use (copy-paste) the result of the console.log instead of using chartOptions as options , the chart is displayed perfectly.

What am I missing here?

Answer 1

The only explanation I can think of (given that copy-pasting it works fine), is that in one instance you are sending a string, and when you copy paste it back in, you then have an object.

So if you look at the console log, it SHOULD look like the first one in the picture above. If it looks like the second, you need to do

chartOptions = JSON.parse(chartOptions);

var chart = new google.visualization.ChartWrapper({
              chartType: chartType,
              dataTable: data,
              options: chartOptions,
              containerId: 'chart'
            });