1# Setting User Preferences (For System Applications Only) 2 3## Use Cases 4 5In addition to system locales and application preferred languages, the system supports setting of user preferences. Currently, the system supports two user preferences: whether to use local digits and whether to use the 12/24-hour format. User preference settings are saved to system locales and application preferred languages as part of the internationalization feature. 6 7## How to Develop 8 9For details about how to use the APIs, see [setUsingLocalDigit](../reference/apis-localization-kit/js-apis-i18n-sys.md#setusinglocaldigit9) and [set24HourClock](../reference/apis-localization-kit/js-apis-i18n-sys.md#set24hourclock9). 10 11 121. Import the **intl** module. 13 ```ts 14 import { i18n, intl } from '@kit.LocalizationKit'; 15 import { BusinessError } from '@kit.BasicServicesKit'; 16 ``` 17 182. Obtain the preferred language of an application. 19 ```ts 20 // Obtain the preferred language of an application. 21 let appPreferredLanguage: string = i18n.System.getAppPreferredLanguage(); 22 ``` 23 243. Enable display of local digits on the application page. 25 ```ts 26 try { 27 i18n.System.setUsingLocalDigit(true); // Enable use of local digits. 28 } catch (error) { 29 let err: BusinessError = error as BusinessError; 30 console.error(`call System.setUsingLocalDigit failed, error code: ${err.code}, message: ${err.message}.`); 31 } 32 let date: Date = new Date(2023, 9, 25); // The date is 2023-10-25. 33 let appPreferredLanguage: string = 'ar'; 34 let dateTimeFmt: intl.DateTimeFormat = new intl.DateTimeFormat(appPreferredLanguage); 35 let formattedTime: string = dateTimeFmt.format(date); // formattedTime = '٢٠٢٣/١٠/٢٥' (represented by localized numbers in Arabic) 36 ``` 37 384. Set the 24-hour clock format. 39 ```ts 40 try { 41 i18n.System.set24HourClock (true); // Set the system time to the 24-hour clock. 42 } catch (error) { 43 let err: BusinessError = error as BusinessError; 44 console.error(`call System.set24HourClock failed, error code: ${err.code}, message: ${err.message}.`); 45 } 46 let date: Date = new Date(2023, 9, 25, 16, 48, 0); // The date and time is 2023-10-25 16:48:00. 47 let appPreferredLanguage: string = 'zh'; 48 let dateTimeFmt: intl.DateTimeFormat = new intl.DateTimeFormat(appPreferredLanguage, { timeStyle: 'medium' }); 49 let formattedTime: string = dateTimeFmt.format(date); // formattedTime = '16:48:00' 50 ``` 51