labelBorderThickness: Number

Sets the border thickness of axisX crosshair’s label.

var  chart =  new  CanvasJS.Chart("container",
{
 .
 .
 axisX:{
    crosshair:{  
	  labelBorderColor: "black",
          labelBorderThickness: 1,
	  .
	  .
    },
 },
 .
 . 
});
chart.render();