legendMarkerBorderThickness: Number

Sets the thickness of the Legend’s Marker Border in pixels. This property works only with Pie and Doughnut charts. If not set, takes the value from dataSeries’ legendMarkerBorderThickness if present.

• There is no border in Legend Marker Type “cross”, hence legendMarkerBorderThickness doesn’t apply when legendMarkerType is “cross”

var  chart =  new  CanvasJS.Chart("container",
{
 .
 .
  data:[ {
   dataPoints: [
    {x: 10 , y: 50 ,   legendMarkerBorderThickness: 4 },

   ],

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