markerType: String

Sets marker type to be rendered at each dataPoint. If mentioned at dataSeries, markers set here will take precedence.

• To disable marker set markerType to “none”.
• Markers can be used in All line charts, area charts, scatter chart and bubble Chart.

var  chart =  new  CanvasJS.Chart("container",
{
 .
 .
  data:[ {
   dataPoints: [
    {x: 10 , y: 50 , markerType: "square"},

   ],

  },
 ]
 .
 .
});
chart.render();