The mouseup
event is fired at an Element
when a button on a pointing device (such as a mouse or trackpad) is released while the pointer is located inside it. mouseup events are the counterpoint to mousedown
events.
Bubbles | Yes |
---|---|
Cancelable | Yes |
Interface | MouseEvent |
Event handler property | onmouseup |
Examples
The following example uses the mousedown
, mousemove
, and mouseup
events to allow the user to draw on an HTML5 canvas. Its functionality is simple: the thickness of the line is set to 1, and the color is always black.
When the page loads, constants myPics
and context
are created to store a reference to the canvas and the 2d context we will use to draw. Finally, the constant rect
is created to store the coordinates of the canvas relative to the page.
Drawing begins when the mousedown
event fires. First we store the x and y coordinates of the mouse pointer in the variables x
and y
, and then set isDrawing
to true.
As the mouse moves over the page, the mousemove
event fires. If isDrawing
is true, the event handler calls the drawLine function to draw a line from the stored x
and y
values to the current location. (Remember, the current x and y values are modified using the rect
constant to adjust the coordinates so they are relative to the upper-left of the canvas.)
When the drawLine()
function returns, we adjust the coordinates and then save them in x
and y
.
The mouseup
event draws the final line segment, sets x
and y
to 0
, and stops further drawing by setting isDrawing
to false
.
HTML
<h1>Drawing with mouse events</h1> <canvas id="myPics" width="560" height="360"></canvas>
CSS
canvas { border: 1px solid black; width: 560px; height: 360px; }
JavaScript
// When true, moving the mouse draws on the canvas let isDrawing = false; let x = 0; let y = 0; const myPics = document.getElementById('myPics'); const context = myPics.getContext('2d'); // The x and y offset of the canvas from the edge of the page const rect = myPics.getBoundingClientRect(); // Add the event listeners for mousedown, mousemove, and mouseup myPics.addEventListener('mousedown', e => { x = e.clientX - rect.left; y = e.clientY - rect.top; isDrawing = true; }); myPics.addEventListener('mousemove', e => { if (isDrawing === true) { drawLine(context, x, y, e.clientX - rect.left, e.clientY - rect.top); x = e.clientX - rect.left; y = e.clientY - rect.top; } }); window.addEventListener('mouseup', e => { if (isDrawing === true) { drawLine(context, x, y, e.clientX - rect.left, e.clientY - rect.top); x = 0; y = 0; isDrawing = false; } }); function drawLine(context, x1, y1, x2, y2) { context.beginPath(); context.strokeStyle = 'black'; context.lineWidth = 1; context.moveTo(x1, y1); context.lineTo(x2, y2); context.stroke(); context.closePath(); }
Result
Specifications
Specification | Status |
---|---|
UI Events The definition of 'mouseup' in that specification. |
Working Draft |
Document Object Model (DOM) Level 3 Events Specification The definition of 'mouseup' in that specification. |
Obsolete |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
mouseup event | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support