html5中的video這個標簽是引入視頻的，通過navigator.getUserMedia去獲取攝像頭的視頻流，所以要在事件裏用關閉的代碼都不能執行關閉攝像頭，只有關閉網頁，攝像頭才關閉。
以下為html5打開攝像頭代碼：
<!DOCTYPE html>
<html>
<head>
<meta content="text/html; charset=UTF-8" http-equiv="content-type">
<title>Smart Home - Camera</title>
<link href="css/main.css" rel="stylesheet" type="text/css">
<script src="js/jq.js"></script>
<script type="text/javascript">
/*
*/
function init(t){
accessLocalWebCam("camera_box");
}
// Normalizes window.URL
window.URL = window.URL || window.webkitURL || window.msURL || window.oURL;
// Normalizes navigator.getUserMedia
navigator.getUserMedia = navigator.getUserMedia ||?
navigator.webkitGetUserMedia|| navigator.mozGetUserMedia ||?
navigator.msGetUserMedia;
function isChromiumVersionLower() {
var ua = navigator.userAgent;
var testChromium = ua.match(/AppleWebKit\/.* Chrome\/([\d.]+).* Safari\//);
return (testChromium && (parseInt(testChromium[1].split('.')[0]) < 19));
}
function successsCallback(stream) {
document.getElementById('camera_errbox').style.display = 'none';
document.getElementById('camera_box').src = (window.URL?
&& window.URL.createObjectURL) ?
window.URL.createObjectURL(stream) : stream;
}
function errorCallback(err) {
}
function accessLocalWebCam(id) {
try {
// Tries it with spec syntax
navigator.getUserMedia({ video: true }, successsCallback, errorCallback);
} catch (err) {
// Tries it with old spec of string syntax
navigator.getUserMedia('video', successsCallback, errorCallback);
}
}
</script>
<style type="text/css">
#camera_errbox{
width:320px; height:auto; border:1px solid #333333; padding:10px;
color:#fff; text-align:left;margin:20px auto;
font-size:14px;
}
#camera_errbox b{
padding-bottom:15px;
}
</style>
</head>
<body onLoad="init(this)" oncontextmenu="return false" onselectstart="return false">
<div>
<div id="mainbox">
<div id="bt_goback"></div>
<div></div><div id="t_iconbox"?
class="icon_12"></div><div id="t_text">
<div id="el_title">Camera</div>
<div id="el_descr"></div>
</div>
<div></div>
<div><span?
class="sp_title_text">Camera</span><div class="sp_oc?
sp_oc_1"></div></div>
<dl id="el_actionbox" style="text-align:center;">
<video id="camera_box" autoplay="" src=""></video>
<div id="camera_errbox">
<b>請點擊“允許”按鈕，授權網頁訪問您的攝像頭！</b>
<div>若您並未看到任何授權提示，則表示您的瀏覽器不支持Media Capture或您的機器沒有連接攝像頭設備。</div>
</div>
</dl>
</div>
</div>
</body>
</html>
-——代碼結束