Create 最稳定的计时器方式.js

Rain120 · Jun 7, 2019 · a4a46a4 · a4a46a4
1 parent 18b6e71
commit a4a46a4
Showing 1 changed file with 19 additions and 0 deletions.
diff --git a/最稳定的计时器方式.js b/最稳定的计时器方式.js
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+// setInterval 虽然时间上设置的是1s，但实际执行，并不是真正意义上的1s，所以长时间或者在其他环境下可能会受到影响
+// requestAnimationFrame 则是通过帧数来计算时间, 1000 / 60 = 16.667
+
+// 60s
+var last_time = new Date().getTime();
+var count = 1;
+var countDownId = null;
+var countDown = () => {
+    if (new Date().getTime() - last_time >= 1000) {
+        count++;
+        if (count > 60) {
+            count = 1;
+        }
+        console.log(count)
+        last_time = new Date().getTime();
+    }
+	countDownId = window.requestAnimationFrame(countDown);
+};
+countDownId = window.requestAnimationFrame(countDown);