Javascript 如何将highcharts系列图形的颜色更改为黑色&；将其作为图像下载时为白色？

下面是图表的链接

I was trying to download the highcharts.js line graph in the black and white image during downloading in spite of the colors which are randomly generated in the graph. But I am not getting how can I achieve this. 

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使用“导出”选项将默认颜色更改为黑色：

https://jsfiddle.net/gh/get/library/pure/highcharts/highcharts/tree/master/samples/highcharts/demo/line-basic/

I want the graph to be black and white during downloading only and I want them to stay colorful during the rendering. Right now it is downloading as a colorful image. 

Thanks in advance because I am a novice in the highcharts. I am stuck in this position. Please help me out.

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以下是一个

您可以通过

图表选项

属性更改导出的颜色：

exporting: {
        chartOptions: {
            colors: ['#000000', '#000000', '#000000', '#000000', '#000000'],
        }
    },

现场演示：

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API参考资料：

到目前为止，您尝试了什么？您只是链接了Highcharts演示，而不是您的代码。我不知道如何继续。这就是我问这个问题的原因@core972。非常感谢，这就是我要找的：）谢谢支持：）

exporting: {
    chartOptions: {
        ...
    }
}