markerBorderThickness: Number

Sets the thickness of the Marker’s Border in pixels.

• Set markerBorderColor to a different color than markerColor to see border appear around marker.
• There is no border in Marker Type “cross”, hence markerBorderThickness doesn’t apply when markerType is “cross”

var  chart =  new  CanvasJS.Chart("container",
{
 .
 .
 data: [{
  markerBorderThickness: 4,

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