Javascript math.round 阈值

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我正在跟踪一个我想以 5 秒间隔触发的计时器。问题是通过我的测试

if (Math.round(time.position) % 5 === 0){do stuff}

触发次数过多。它将触发所有 9.~ 十进制值。我怎样才能让它以 5 秒的间隔触发？

time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 9.29} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 9.43} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 9.54} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 9.68} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 9.79} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 9.92} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.03} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.18} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.29} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.42} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.54} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.68} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.79} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 10.92} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 11.04} index.html:104
time:  Object {duration: 149.49, type: "jwplayerMediaTime", position: 11.17} 

Answer 1

我相信这将每 5 秒触发一次。

var previousValue = 1;
if(Math.ceil(time.position / 5) !== previousValue) {
    previousValue = Math.ceil(time.position / 5);
}

请确保只调用第一行一次。