HC connectNull Demo

author(s): Marc

by J. Albert Bowden

HTML

<script src="https://code.highcharts.com/highcharts.js"></script>

<div id="container" style="height: 400px; max-width: 800px; margin: 0 auto"></div>

JavaScript

var data = [4, 5, 1, null, 3, 4, null, 1, 5, null,4];
$(function () {
    $('#container').highcharts({
        title: {
            text: 'LineWithNulls'
        },
        subtitle: {
            text: 'How can I connect the the line in a different color or with a dotted line'
        },
        xAxis: {
            categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'],
        },
        series: [{
            data: data ,
            connectNulls: false
        }]
    });
    
    var chart = $('#container').highcharts();
    var plotLeft = chart.plotLeft;
		var plotTop = chart.plotTop;

    for(var i=0;i<data.length;i++){
      var path = [];
    	if(data[i] == null){
        	var p1 = chart.series[0].points[i-1],
          	  p2 = chart.series[0].points[i+1];
          
          p2 = p2 == undefined ? p1 : p2;
        	path.push('M');
          path.push(p1.plotX+plotLeft, p1.plotY+plotTop);
          path.push('L');
					path.push(p2.plotX+plotLeft, p2.plotY+plotTop);
      }
   
       var line = chart.renderer.path(path)
          .attr({
            'stroke-width': 2,
            stroke: Highcharts.getOptions().colors[0],
            dashstyle: 'ShortDash'
       })
       .add();
    }
});