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onlosecapture event | losecapture event

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Browser support:

Occurs when the object loses the mouse capture.

To set an object to capture mouse events, use the setCapture method. To remove the mouse capture, use the releaseCapture method. For further details about the capturing mechanism, please see the page for the setCapture method.

How to register:

In HTML:

In JavaScript:

object.onlosecapture = handler;

object.attachEvent ("onlosecapture", handler);

You can find the related objects in the Supported by objects section below.

The event object is accessible to all event handlers in all browsers. The properties of the event object contain additional information about the current event. To get further details about these properties and the possible event handler registration methods, please see the page for the event object.

For a complete list of events, see the page for Events in JavaScript.

Basic information:

Bubbles	No
Cancelable	No
Type	Event

Actions that invoke the onlosecapture event:

If an object captures mouse events and the setCapture method is invoked on another element.
If an object captures mouse events and the releaseCapture method is invoked on it.
If an object captures mouse events and its owner window becomes inactive.

Example HTML code 1:

This example illustrates the capturing mechanism in Internet Explorer:

<head>
    <style>
        #square {
            position:absolute;
            left:200px;
            top:200px;
            width:20px;
            height:20px;
            background:red;
        }
    </style>
    <script>
        var capturing = false;

        function ToggleCapture () {
            var square = document.getElementById ("square");
            if (square.setCapture) {
                if (capturing) {
                    square.releaseCapture ();
                }
                else {
                    capturing = true;
                    square.setCapture ();
                }
            }
        }

        function OnLoseCapture () {
            capturing = false;
        }
        
        function MoveSquare () {
            if (capturing) {
                var square = document.getElementById ("square");
                square.style.left = event.clientX + "px";
                square.style.top = event.clientY + "px";
            }
        }
    </script>
</head>
<body onkeydown="ToggleCapture ();"> <br />
    <h3 style="text-align:center">Press any key to toggle capture!</h3>
    While mouse events are captured, the square follows the mouse.
    <div id="square" onmousemove="MoveSquare ();" onlosecapture="OnLoseCapture ()"></div>
</body>

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Example HTML code 2:

This example illustrates a cross-browser solution for the previous example:

<head>
    <style>
        #square {
            position:absolute;
            left:200px;
            top:200px;
            width:20px;
            height:20px;
            background:red;
        }
    </style>
    <script>
        var capturing = false;

        function ToggleCapture () {
            var square = document.getElementById ("square");
            if (capturing) {
                if (square.releaseCapture) {
                    square.releaseCapture ();
                }
                else {
                    if (document.body.removeEventListener) {
                        capturing = false;
                        window.removeEventListener ("mousemove", MoveSquare, true);
                    }
                }
            }
            else {
                if (square.setCapture) {
                    capturing = true;
                    square.setCapture ();
                }
                else {
                    if (document.body.addEventListener) {
                        capturing = true;
                        window.addEventListener ("mousemove", MoveSquare, true);
                    }
                }
            }
        }

        function OnLoseCapture () {
            capturing = false;
        }
        
        function MoveSquare (event) {
            if (capturing) {
                var square = document.getElementById ("square");
                square.style.left = event.clientX + "px";
                square.style.top = event.clientY + "px";
            }
        }
    </script>
</head>
<body onkeydown="ToggleCapture ();"> <br />
    <h3 style="text-align:center">Press any key to toggle capture!</h3>
    While mouse events are captured, the square follows the mouse.
    <div id="square" onmousemove="MoveSquare (event);" onlosecapture="OnLoseCapture ()"></div>
</body>