MouseEvent

The MouseEvent interface represents events that occur due to the user interacting with a pointing device (such as a mouse). Common events using this interface include click, dblclick, mouseup, mousedown.

MouseEvent derives from UIEvent, which in turn derives from Event. Though the MouseEvent.initMouseEvent() method is kept for backward compatibility, creating of a MouseEvent object should be done using the MouseEvent() constructor.

Several more specific events are based on MouseEvent, including WheelEvent and DragEvent.

Constructor

MouseEvent()

Creates a MouseEvent object.

Properties

This interface also inherits properties of its parents, UIEvent and Event.

MouseEvent.altKey Read only

Returns true if the alt key was down when the mouse event was fired.

MouseEvent.button Read only

The button number that was pressed (if applicable) when the mouse event was fired.

MouseEvent.buttons Read only

The buttons being depressed (if any) when the mouse event was fired.

MouseEvent.clientX Read only

The X coordinate of the mouse pointer in local (DOM content) coordinates.

MouseEvent.clientY Read only

The Y coordinate of the mouse pointer in local (DOM content) coordinates.

MouseEvent.ctrlKey Read only

Returns true if the control key was down when the mouse event was fired.

MouseEvent.metaKey Read only

Returns true if the meta key was down when the mouse event was fired.

MouseEvent.movementX Read only

The X coordinate of the mouse pointer relative to the position of the last mousemove event.

MouseEvent.movementY Read only

The Y coordinate of the mouse pointer relative to the position of the last mousemove event.

MouseEvent.offsetX Read only

The X coordinate of the mouse pointer relative to the position of the padding edge of the target node.

MouseEvent.offsetY Read only

The Y coordinate of the mouse pointer relative to the position of the padding edge of the target node.

MouseEvent.pageX Read only

The X coordinate of the mouse pointer relative to the whole document.

MouseEvent.pageY Read only

The Y coordinate of the mouse pointer relative to the whole document.

MouseEvent.region Read only

Returns the id of the hit region affected by the event. If no hit region is affected, null is returned.

MouseEvent.relatedTarget Read only

The secondary target for the event, if there is one.

MouseEvent.screenX Read only

The X coordinate of the mouse pointer in global (screen) coordinates.

MouseEvent.screenY Read only

The Y coordinate of the mouse pointer in global (screen) coordinates.

MouseEvent.shiftKey Read only

Returns true if the shift key was down when the mouse event was fired.

MouseEvent.which Read only

The button being pressed when the mouse event was fired.

MouseEvent.mozPressure Read only

The amount of pressure applied to a touch or tablet device when generating the event; this value ranges between 0.0 (minimum pressure) and 1.0 (maximum pressure).

MouseEvent.mozInputSource Read only

The type of device that generated the event (one of the MOZ_SOURCE_* constants listed below). This lets you, for example, determine whether a mouse event was generated by an actual mouse or by a touch event (which might affect the degree of accuracy with which you interpret the coordinates associated with the event).

MouseEvent.webkitForce Read only

The amount of pressure applied when clicking

MouseEvent.x Read only

Alias for MouseEvent.clientX.

MouseEvent.y Read only

Alias for MouseEvent.clientY

Constants

MouseEvent.WEBKIT_FORCE_AT_MOUSE_DOWN Read only

Minimum force necessary for a normal click

MouseEvent.WEBKIT_FORCE_AT_FORCE_MOUSE_DOWN Read only

Minimum force necessary for a force click

Methods

This interface also inherits methods of its parents, UIEvent and Event.

MouseEvent.getModifierState()

Returns the current state of the specified modifier key. See the KeyboardEvent.getModifierState() for details.

MouseEvent.initMouseEvent()

Initializes the value of a MouseEvent created. If the event has already being dispatched, this method does nothing.

Example

This example demonstrates simulating a click (that is programmatically generating a click event) on a checkbox using DOM methods.

function simulateClick() {
  var evt = new MouseEvent("click", {
    bubbles: true,
    cancelable: true,
    view: window
  });
  var cb = document.getElementById("checkbox"); //element to click on
  var canceled = !cb.dispatchEvent(evt);
  if(canceled) {
    // A handler called preventDefault
    alert("canceled");
  } else {
    // None of the handlers called preventDefault
    alert("not canceled");
  }
}
document.getElementById("button").addEventListener('click', simulateClick);

<p><label><input type="checkbox" id="checkbox"> Checked</label>
<p><button id="button">Click me</button>

Click on the button to see how the sample works:

Specifications

Browser compatibility

[1] Requires enabling the ExperimentalCanvasFeatures flag.

See also

• Its direct parent, UIEvent.