根据key取值 

根据key、data更新数组 

我的需求是缓存一个阅读记录的字典其数据格式如下

1. read_record: {
2. keys: Array(), // [小说id]
3. datas: Array() // [章节id]
4. }

可以根据小说id去获取最近阅读的章节的id

1. data: {
2. read_record: {
3. keys: Array(),
4. datas: Array()
5. }
6. },
7. // 初始化阅读记录
8. initReadRecord: function() {
9. let key = 'chapter_read_record'
10. var data = wx.getStorageSync(key)
11. if (data) {
12. this.data.read_record = data
13. }
14. },
15. // 获取阅读记录 根据小说的id获取上次阅读的章节的id
16. getReadRecord: function(novel_id) {
17. let keys = this.data.read_record.keys
18. let datas = this.data.read_record.datas
19. let idx = keys.indexOf(novel_id)
20. return datas[idx]
21. },
22. // 保存阅读记录 根据小说id、章节id保存
23. setReadRecord: function(novel_id, chapter_id) {
24. let key = 'chapter_read_record'
25.  
26. let keys = this.data.read_record.keys
27. let datas = this.data.read_record.datas
28.  
29. let idx = keys.indexOf(novel_id)
30. // 如果没有找到索引，会返回-1
31. if (idx == -1) {
32. keys.push(novel_id)
33. datas.push(chapter_id)
34. } else {
35. datas[idx] = chapter_id
36. }
37.  
38. let that = this
39. wx.setStorage({
40. key: key,
41. data: that.data.read_record,
42. })
43. },

缓存结果