1# Timing and Time 2 3## Introduction 4 5The timing and time module provides APIs for managing the system time. 6 7**Figure 1** Subsystem architecture 8 9 10 11## Directory Structure 12 13``` 14/base/time/time_service 15├── etc # Process configuration files 16├── figures # Architecture diagram 17├── framework/js/napi # the js interface resolves to the napi interface 18├── interfaces/inner_api # external interface code provided by the component 19├── services # time service realization 20│ └── sa_profile # module contains the config files of system services and processes 21├── test # unit test of interface 22└── utils # module contains log printing and constants for ordered commonEvent 23``` 24 25 26## Usage 27 28### Available JS APIs 29 30**Table 1** Major functions of systemTime 31 32| Interface name | describe | 33| ------------------------------------------------------------ | ------------------------------------------------------------ | 34| setTime(time : number) : Promise<boolean> | Set the system time (1970-01-01 to the present in milliseconds), Promise method. | 35| setTime(time : number, callback : AsyncCallback<boolean>) : void | Set the system time (1970-01-01 to the present in milliseconds), callback mode. | 36| setDate(date: Date, callback: AsyncCallback<boolean>): void; | Set the system time (Date format), Promise method. | 37| setDate(date: Date): Promise<boolean> | Set system time (Date format), callback method. | 38| setTimezone(timezone: string, callback: AsyncCallback<boolean>): void | Set the system time zone, callback method. | 39| setTimezone(timezone: string): Promise<boolean> | Set the system time zone, Promise method. | 40 41**表 2** Major functions of systemTimer 42 43| Interface name | describe | 44| ------------------------------------------------------------ | ------------------------------------- | 45| createTimer(options: TimerOptions, callback: AsyncCallback<number>): void | Create timer, callback method | 46| createTimer(options: TimerOptions): Promise<number> | Create timer, promise method | 47| startTimer(timer: number, triggerTime: number, callback: AsyncCallback<boolean>): void | Start the timer, callback mode | 48| startTimer(timer: number, triggerTime: number): Promise<boolean> | Start the timer, promise mode | 49| stopTimer(timer: number, callback: AsyncCallback<boolean>): void | Stop the timer, callback mode | 50| stopTimer(timer: number): Promise<boolean> | Stop the timer, promise mode | 51| destroyTimer(timer: number, callback: AsyncCallback<boolean>): void | Destroy the timer, callback method | 52| destroyTimer(timer: number): Promise<boolean> | Destroy the timer, the promise method | 53 54**表 3** parameter TimerOptions description of systemTimer 55 56| name | type | illustrate | 57| --------- | --------- | ------------------------------------------------------------ | 58| type | number | Timer type. <br/>If the value is 1, it is represented as the system startup time timer (the timer start time cannot be later than the currently set system time); <br/>If the value is 2, it is indicated as a wake-up timer; <br/>When the value is 4, it is represented as a precision timer; <br/>If the value is 5, it is represented as an IDLE mode timer (not supported). | 59| repeat | boolean | true Is a cyclic timer, false is a single timer. | 60| interval | number | If it is a cyclic timer, the repeat value should be greater than 5000 milliseconds, and the non-repeated timer is set to 0. | 61| wantAgent | wantAgent | Set the wantagent to notify, and notify when the timer expires. | 62| callback | => void | Set the callback function, which will be triggered after the timer expires. | 63 64### Sample Code 65 66Example fo using systemTime 67 68```javascript 69// Import the module. 70import systemTime from '@ohos.systemTime'; 71 72// Set the system time asynchronously with a Promise. 73var time = 1611081385000; 74systemTime.setTime(time).then((value) => { 75 console.log(`success to systemTime.setTime: ${value}`); 76}).catch((err) => { 77 console.error(`failed to systemTime.setTime because ${err.message}`) 78}); 79 80// Set the system time asynchronously with a callback. 81var time = 1611081385000; 82systemTime.setTime(time, (err, value) => { 83 if (err) { 84 console.error(`failed to systemTime.setTime because ${err.message}`); 85 return; 86 } 87 console.log(`success to systemTime.setTime: ${value}`); 88}); 89``` 90Example fo using systemTimer 91```javascript 92// Import the module 93import systemTimer from '@ohos.systemTimer'; 94 95console.log("start"); 96var options:TimerOptions{ 97 type:TIMER_TYPE_REALTIME, 98 repeat:false, 99 interval:Number.MAX_VALUE/2, 100 persistent:false 101} 102 103console.log("create timer") 104let timerId = systemTimer.Timer(options) 105console.log("start timer") 106let startTimerRes = systemTimer.startTimer(timerId, 100000) 107console.log("stop timer") 108let stopTimerRes = systemTimer.stopTimer(timerId) 109console.log("destroy timer") 110let destroyTimerRes = systemTimer.destroyTimer(timerId) 111console.log('end'); 112``` 113 114## Repositories Involved 115 116**Time/Timezone subsystem** 117 118[time\_time\_service](https://gitee.com/openharmony/time_time_service/tree/master/) 119 120
