wxml文件放个text

second: {{second}} micro second:{{micro_second}}

在js文件中调用

1. function countdown(that) {
2. var second = that.data.second
3. if (second == 0) {
4. // console.log("Time Out...");
5. that.setData({
6. second: "Time Out..."
7. });
8. return ;
9. }
10. var time = setTimeout(function(){
11. that.setData({
12. second: second - 1
13. });
14. countdown(that);
15. }
16. ,1000)
17. }
18.  
19. Page({
20. data: {
21. second: 3
22. },
23. onLoad: function() {
24. countdown(this);
25. }
26. });

运行验证下，从10走到1s，然后显示时间到。

于是继续将毫秒完善，注意毫秒的步长受限于系统的时间频率，于是我们精确到0.01s即10ms

js

1. /* 秒级倒计时 */
2. function countdown(that) {
3. var second = that.data.second
4. if (second == 0) {
5. that.setData({
6. second: "Time out!",
7. micro_second: "micro_second too."
8. });
9. clearTimeout(micro_timer);
10. return ;
11. }
12. var timer = setTimeout(function(){
13. that.setData({
14. second: second - 1
15. });
16. countdown(that);
17. }
18. ,1000)
19. }
20.  
21. /* 毫秒级倒计时 */
22. // 初始毫秒数，同时用作归零
23. var micro_second_init = 100;
24. // 当前毫秒数
25. var micro_second_current = micro_second_init;
26. // 毫秒计时器
27. var micro_timer;
28.  
29. function countdown4micro(that) {
30. if (micro_second_current <= 0) {
31. micro_second_current = micro_second_init;
32. }
33. micro_timer = setTimeout(function(){
34. that.setData({
35. micro_second: micro_second_current - 1
36. });
37. micro_second_current--;
38. countdown4micro(that);