crosshair: Object

Crosshairs are interactive vertical or horizontal lines with label that shows the x & y axis values at the current mouse co-ordinates or the nearest data points.

You can customize the appearance of crosshair line using thickness, lineColor, lineDashType etc and labels using labelColor, labelBackgroundColor, labelFontSize, labelFontStyle, etc.

Crosshairs can be displayed using Axis X or Axis Y’s crosshair object. This allows you to have crosshair on both x & y axis.

Here is an example:

var  chart =  new  CanvasJS.Chart("container", 
{
 .
 .
 axisX: {
    crosshair: {
        enabled: true,
	color: "orange",
	labelFontColor: "#F8F8F8"
    }
 },
 .
 .
});
chart.render();