Web/API/MouseEvent/region

The MouseEvent.region read-only property returns the id of the canvas hit region affected by the event. If no hit region is affected, null is returned.

Syntax

var hitRegion = instanceOfMouseEvent.region

Return value

A DOMString representing the id of the hit region.

Example

Example of using the event.region combined with CanvasRenderingContext2D.addHitRegion() method.

<canvas id="canvas"></canvas>

<script>
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");

ctx.beginPath();
ctx.arc(70, 80, 10, 0, 2 * Math.PI, false);
ctx.fill();
ctx.addHitRegion({id: "circle"});

canvas.addEventListener("mousemove", function(event){
  if(event.region) {
    console.log("hit region: " + event.region);
  }
});
</script>

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`region`	Chrome Full support Yes Disabled' Full support Yes Disabled' Disabled' This feature is behind the `Experimental Web Platform Features` preference (needs to be set to `true`). To change preferences in Chrome, visit chrome://flags.	Edge Full support ≤79 Disabled' Full support ≤79 Disabled' Disabled' From version ≤79: this feature is behind the `Experimental Web Platform Features` preference (needs to be set to `true`).	Firefox Full support 30 Disabled' Full support 30 Disabled' Disabled' From version 30: this feature is behind the `canvas.hitregions.enabled` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	IE No support No	Opera No support No	Safari No support No	WebView Android No support No	Chrome Android No support No	Firefox Android Full support 30 Disabled' Full support 30 Disabled' Disabled' From version 30: this feature is behind the `canvas.hitregions.enabled` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	Opera Android No support No	Safari iOS No support No	Samsung Internet Android No support No

Legend

Full support: Full support
No support: No support
User must explicitly enable this feature.': User must explicitly enable this feature.