Weitere ähnliche Inhalte Ähnlich wie Timers in Browser (20) Timers in Browser4. 定时器
setTimeout
返回值: (number) ID
clearTimeout(ID)
setInterval
返回值: (number) ID
clearInterval(ID)
11. 浏览器处理
旧版本:依赖系统时钟
HTML5:4ms
IE9/Chrome/FF5/safari5.1/Opera11已实现
电池供电时,Chrome/IE9+切换到系统时钟
FF5+/Chrome 11+/IE10+空闲标签变为1000ms
Safari on iOS 5 / Silk on Kindle Fire:切出应用时冻结
Timer resolution in browsers
18. 取客户端时间校正
var timeLeft = 123456ms,
timeStart = new Date().getTime();
// after some time …
var timeNow = new Date().getTime();
timeLeft = timeLeft – (timeNow – timeStart) ;
30. 代码
var a = setTimeout(fn0, 1000);
//…
a = setTimeout(fn1, 3000);
31. 代码
var a = setTimeout(fn0, 1000);
//…
a = setTimeout(fn1, 3000);
//
clearTimeout(a);
37. 替代方案
web workers:HTML5 多线程方案
主线程:
var worker = new Worker( url )
worker.postMessage( data )
worker.onmessage
worker.terminate()
新线程
postMessage( data )
onmessage