# Internationalization – I18N

> **NOTE**<br>
> - The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.
>
> - This module provides system-related or enhanced I18N capabilities, such as locale management, phone number formatting, and calendar, through supplementary I18N interfaces that are not defined in ECMA 402. For details about the basic I18N capabilities, see [Intl](js-apis-intl.md).


## Modules to Import

```
import i18n from '@ohos.i18n';
```


## i18n.getDisplayLanguage

getDisplayLanguage(language: string, locale: string, sentenceCase?: boolean): string

Obtains the localized script for the specified language.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name         | Type     | Mandatory  | Description              |
| ------------ | ------- | ---- | ---------------- |
| language     | string  | Yes   | Specified language.           |
| locale       | string  | Yes   | Locale ID.    |
| sentenceCase | boolean | No   | Whether to use sentence case for the localized script.|

**Return value**
| Type    | Description           |
| ------ | ------------- |
| string | Localized script for the specified language.|

**Example**
  ```
  i18n.getDisplayLanguage("zh", "en-GB", true);
  i18n.getDisplayLanguage("zh", "en-GB");
  ```


## i18n.getDisplayCountry

getDisplayCountry(country: string, locale: string, sentenceCase?: boolean): string

Obtains the localized script for the specified country.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name         | Type     | Mandatory  | Description              |
| ------------ | ------- | ---- | ---------------- |
| country      | string  | Yes   | Specified country.           |
| locale       | string  | Yes   | Locale ID.    |
| sentenceCase | boolean | No   | Whether to use sentence case for the localized script.|

**Return value**
| Type    | Description           |
| ------ | ------------- |
| string | Localized script for the specified country.|

**Example**
  ```
  i18n.getDisplayCountry("zh-CN", "en-GB", true);
  i18n.getDisplayCountry("zh-CN", "en-GB");
  ```


## i18n.isRTL<sup>7+</sup>

isRTL(locale: string): boolean

Checks whether the localized script for the specified language is displayed from right to left.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Description     |
| ------ | ------ | ------- |
| locale | string | Locale ID.|

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the localized script is displayed from right to left; returns **false** otherwise.|

**Example**
  ```
  i18n.isRTL("zh-CN");// Since Chinese is not written from right to left, false is returned.
  i18n.isRTL("ar-EG");// Since Arabic is written from right to left, true is returned.
  ```


## i18n.getSystemLanguage

getSystemLanguage(): string

Obtains the system language.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description     |
| ------ | ------- |
| string | System language ID.|

**Example**
  ```
  i18n.getSystemLanguage();
  ```


## i18n.setSystemLanguage

setSystemLanguage(language: string): boolean

Sets the system language.

This is a system API.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name     | Type    | Description   |
| -------- | ------ | ----- |
| language | string | Language ID.|

**Return value**
| Type     | Description                                   |
| ------- | ------------------------------------- |
| boolean | Returns **true** if the operation is successful; returns **false** otherwise.|

**Example**
  ```
  i18n.setSystemLanguage('zh');
  ```


## i18n.getSystemLanguages

getSystemLanguages(): Array&lt;string&gt;

Obtains the list of system languages.

**System capability**: SystemCapability.Global.I18n

**System API**: This is a system API and cannot be called by third-party applications.

**Return value**
| Type                 | Description          |
| ------------------- | ------------ |
| Array&lt;string&gt; | List of the IDs of system languages.|

**Example**
  ```
  i18n.getSystemLanguages();
  ```


## i18n.getSystemCountries

getSystemCountries(language: string): Array&lt;string&gt;

Obtains the list of countries and regions supported for the specified language.

**System capability**: SystemCapability.Global.I18n

**System API**: This is a system API and cannot be called by third-party applications.

**Parameters**
| Name     | Type    | Description   |
| -------- | ------ | ----- |
| language | string | Language ID.|

**Return value**
| Type                 | Description          |
| ------------------- | ------------ |
| Array&lt;string&gt; | List of the IDs of the countries and regions supported for the specified language.|

**Example**
  ```
  i18n.getSystemCountries('zh');
  ```


## i18n.getSystemRegion

getSystemRegion(): string

Obtains the system region.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description     |
| ------ | ------- |
| string | System region ID.|

**Example**
  ```
  i18n.getSystemRegion();
  ```


## i18n.setSystemRegion

setSystemRegion(region: string): boolean

Sets the system region.

This is a system API.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Description   |
| ------ | ------ | ----- |
| region | string | Region ID.|

**Return value**
| Type     | Description                                   |
| ------- | ------------------------------------- |
| boolean | Returns **true** if the operation is successful; returns **false** otherwise.|

**Example**
  ```
  i18n.setSystemRegion('CN');
  ```


## i18n.getSystemLocale

getSystemLocale(): string

Obtains the system locale.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description     |
| ------ | ------- |
| string | System locale ID.|

**Example**
  ```
  i18n.getSystemLocale();
  ```


## i18n.setSystemLocale

setSystemLocale(locale: string): boolean

Sets the system locale.

This is a system API.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Description             |
| ------ | ------ | --------------- |
| locale | string | System locale ID, for example, **zh-CN**.|

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the operation is successful; returns **false** otherwise.|

**Example**
  ```
  i18n.setSystemLocale('zh-CN');
  ```


## i18n.isSuggested

isSuggested(language: string, region?: string): boolean

Checks whether the system language matches the specified region.

**System capability**: SystemCapability.Global.I18n

**System API**: This is a system API and cannot be called by third-party applications.

**Parameters**
| Name     | Type    | Mandatory  | Description           |
| -------- | ------ | ---- | ------------- |
| language | string | Yes   | Valid language ID, for example, **zh**.|
| region   | string | No   | Valid region ID, for example, **CN**. |

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the system language matches the specified region; returns **false** otherwise.|

**Example**
  ```
  i18n.isSuggested('zh', 'CN');
  ```


## i18n.getCalendar<sup>8+</sup>

getCalendar(locale: string, type? : string): Calendar

Obtains a **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description                                      |
| ------ | ------ | ---- | ---------------------------------------- |
| locale | string | Yes   | Valid locale value, for example, **zh-Hans-CN**.                |
| type   | string | No   | Valid calendar type. Currently, the valid types are as follows: **buddhist**, **chinese**, **coptic**, **ethiopic**, **hebrew**, **gregory**, **indian**, **islamic\_civil**, **islamic\_tbla**, **islamic\_umalqura**, **japanese**, and **persian**. If this parameter is left unspecified, the default calendar type of the specified locale is used.|

**Return value**
| Type                    | Description   |
| ---------------------- | ----- |
| [Calendar](#calendar8) | **Calendar** object.|

**Example**
  ```
  i18n.getCalendar("zh-Hans", "gregory");
  ```


## Calendar<sup>8+</sup>


### setTime<sup>8+</sup>

setTime(date: Date): void

Sets the date for this **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type  | Mandatory  | Description               |
| ---- | ---- | ---- | ----------------- |
| date | Date | Yes   | Date to be set for the **Calendar** object.|

**Example**
  ```
  var calendar = i18n.getCalendar("en-US", "gregory");
  var date = new Date(2021, 10, 7, 8, 0, 0, 0);
  calendar.setTime(date);
  ```


### setTime<sup>8+</sup>

setTime(time: number): void

Sets the date and time for this **Calendar** object. The value is represented by the number of milliseconds that have elapsed since the Unix epoch (00:00:00 UTC on January 1, 1970).

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description                                      |
| ---- | ------ | ---- | ---------------------------------------- |
| time | number | Yes   | Number of milliseconds that have elapsed since the Unix epoch.|

**Example**
  ```
  var calendar = i18n.getCalendar("en-US", "gregory");
  calendar.setTime(10540800000);
  ```


### set<sup>8+</sup>

set(year: number, month: number, date:number, hour?: number, minute?: number, second?: number): void

Sets the year, month, day, hour, minute, and second for this **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description    |
| ------ | ------ | ---- | ------ |
| year   | number | Yes   | Year to set. |
| month  | number | Yes   | Month to set. |
| date   | number | Yes   | Day to set. |
| hour   | number | No   | Hour to set.|
| minute | number | No   | Minute to set.|
| second | number | No   | Second to set. |

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.set(2021, 10, 1, 8, 0, 0); // set time to 2021.10.1 08:00:00
  ```


### setTimeZone<sup>8+</sup>

setTimeZone(timezone: string): void

Sets the time zone of this **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name     | Type    | Mandatory  | Description                       |
| -------- | ------ | ---- | ------------------------- |
| timezone | string | Yes   | Time zone, for example, **Asia/Shanghai**.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.setTimeZone("Asia/Shanghai");
  ```


### getTimeZone<sup>8+</sup>

getTimeZone(): string

Obtains the time zone of this **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description        |
| ------ | ---------- |
| string | Time zone of the **Calendar** object.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.setTimeZone("Asia/Shanghai");
  calendar.getTimeZone(); // Asia/Shanghai"
  ```


### getFirstDayOfWeek<sup>8+</sup>

getFirstDayOfWeek(): number

Obtains the start day of a week for this **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                   |
| ------ | --------------------- |
| number | Start day of a week. The value **1** indicates Sunday, and the value **7** indicates Saturday.|

**Example**
  ```
  var calendar = i18n.getCalendar("en-US", "gregory");
  calendar.getFirstDayOfWeek();
  ```


### setFirstDayOfWeek<sup>8+</sup>

setFirstDayOfWeek(value: number): void

Sets the start day of a week for this **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name  | Type    | Mandatory  | Description                   |
| ----- | ------ | ---- | --------------------- |
| value | number | No   | Start day of a week. The value **1** indicates Sunday, and the value **7** indicates Saturday.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.setFirstDayOfWeek(0);
  ```


### getMinimalDaysInFirstWeek<sup>8+</sup>

getMinimalDaysInFirstWeek(): number

Obtains the minimum number of days in the first week of a year.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description          |
| ------ | ------------ |
| number | Minimum number of days in the first week of a year.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.getMinimalDaysInFirstWeek();
  ```


### setMinimalDaysInFirstWeek<sup>8+</sup>

setMinimalDaysInFirstWeek(value: number): void

Sets the minimum number of days in the first week of a year.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name  | Type    | Mandatory  | Description          |
| ----- | ------ | ---- | ------------ |
| value | number | No   | Minimum number of days in the first week of a year.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.setMinimalDaysInFirstWeek(3);
  ```


### get<sup>8+</sup>

get(field: string): number

Obtains the value of the specified field in the **Calendar** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name  | Type    | Mandatory  | Description                                      |
| ----- | ------ | ---- | ---------------------------------------- |
| field | string | Yes   | Value of the specified field in the **Calendar** object. Currently, a valid field can be any of the following: **era**, **year**, **month**, **week\_of\_year**, **week\_of\_month**, **date**, **day\_of\_year**, **day\_of\_week**, **day\_of\_week\_in\_month**, **hour**, **hour\_of\_day**, **minute**, **second**, **millisecond**, **zone\_offset**, **dst\_offset**, **year\_woy**, **dow\_local**, **extended\_year**, **julian\_day**, **milliseconds\_in\_day**, **is\_leap\_month**.|

**Return value**
| Type    | Description                                      |
| ------ | ---------------------------------------- |
| number | Value of the specified field. For example, if the year in the internal date of this **Calendar** object is **1990**, the **get("year")** function will return **1990**.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.set(2021, 10, 1, 8, 0, 0); // set time to 2021.10.1 08:00:00
  calendar.get("hour_of_day"); // 8
  ```


### getDisplayName<sup>8+</sup>

getDisplayName(locale: string): string

Obtains the name of the **Calendar** object displayed for the specified locale.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description                                      |
| ------ | ------ | ---- | ---------------------------------------- |
| locale | string | Yes   | Locale for which the name of the **Calendar** object is displayed. For example, if **locale** is **en-US**, the name of the Buddhist calendar will be **Buddhist Calendar**.|

**Return value**
| Type    | Description                 |
| ------ | ------------------- |
| string | Name of the **Calendar** object displayed for the specified locale.|

**Example**
  ```
  var calendar = i18n.getCalendar("en-US", "buddhist");
  calendar.getDisplayName("zh"); // Obtain the name of the Buddhist calendar in zh.
  ```


### isWeekend<sup>8+</sup>

isWeekend(date?: Date): boolean

Checks whether the specified date in this **Calendar** object is a weekend.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type  | Mandatory  | Description                                      |
| ---- | ---- | ---- | ---------------------------------------- |
| date | Date | No   | Specified date in this **Calendar** object. If this parameter is left unspecified, the system checks whether the current date in the **Calendar** object is a weekend.|

**Return value**
| Type     | Description                                 |
| ------- | ----------------------------------- |
| boolean | Returns **true** if the date is a weekend; returns **false** if the date is a weekday.|

**Example**
  ```
  var calendar = i18n.getCalendar("zh-Hans");
  calendar.set(2021, 11, 11, 8, 0, 0); // set time to 2021.11.11 08:00:00
  calendar.isWeekend(); // false
  var date = new Date(2011, 11, 6, 9, 0, 0);
  calendar.isWeekend(date); // true
  ```


## PhoneNumberFormat<sup>8+</sup>


### constructor<sup>8+</sup>

constructor(country: string, options?: PhoneNumberFormatOptions)

Creates a **PhoneNumberFormat** object.

**System capability**: SystemCapability.Global.I18n

Parameters
| Name    | Type                                      | Mandatory  | Description              |
| ------- | ---------------------------------------- | ---- | ---------------- |
| country | string                                   | Yes   | Country or region to which the phone number to be formatted belongs.|
| options | [PhoneNumberFormatOptions](#phonenumberformatoptions8) | No   | Options of the **PhoneNumberFormat** object. |

**Example**
  ```
  var phoneNumberFormat= new i18n.PhoneNumberFormat("CN", {"type": "E164"});
  ```


### isValidNumber<sup>8+</sup>

isValidNumber(number: string): boolean

Checks whether the format of the specified phone number is valid.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description       |
| ------ | ------ | ---- | --------- |
| number | string | Yes   | Phone number to be checked.|

**Return value**
| Type     | Description                                   |
| ------- | ------------------------------------- |
| boolean | Returns **true** if the phone number format is valid; returns **false** otherwise.|

**Example**
  ```
  var phonenumberfmt = new i18n.PhoneNumberFormat("CN");
  phonenumberfmt.isValidNumber("15812312312");
  ```


### format<sup>8+</sup>

format(number: string): string

Formats a phone number.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description        |
| ------ | ------ | ---- | ---------- |
| number | string | Yes   | Phone number to be formatted.|

**Return value**
| Type    | Description        |
| ------ | ---------- |
| string | Formatted phone number.|

**Example**
  ```
  var phonenumberfmt = new i18n.PhoneNumberFormat("CN");
  phonenumberfmt.format("15812312312");
  ```

### getLocationName<sup>8+</sup>

static getLocationName(number: string, locale: string): string

Obtains the home location of a phone number.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description        |
| ------ | ------ | ---- | ---------- |
| number | string | Yes   | Phone number.|
| locale | string | Yes   | Locale ID.|

**Return value**
| Type    | Description        |
| ------ | ---------- |
| string | Home location of the phone number.|

**Example**
  ```
  var location = i18n.PhoneNumberFormat.getLocationName('15812312345', 'zh-CN');
  ```




## PhoneNumberFormatOptions<sup>8+</sup>

Defines the options for this PhoneNumberFormat object.

**System capability**: SystemCapability.Global.I18n

| Name  | Type  | Readable  | Writable  | Description                                      |
| ---- | ------ | ---- | ---- | ---------------------------------------- |
| type | string | Yes   | Yes   | Format type of a phone number. The available options are as follows: E164,&nbsp;INTERNATIONAL,&nbsp;NATIONAL, and&nbsp;RFC3966.|


## UnitInfo<sup>8+</sup>

Defines the measurement unit information.

**System capability**: SystemCapability.Global.I18n

| Name           | Type  | Readable  | Writable  | Description                                      |
| ------------- | ------ | ---- | ---- | ---------------------------------------- |
| unit          | string | Yes   | Yes   | Name of the measurement unit, for example, **meter**, **inch**, or **cup**.|
| measureSystem | string | Yes   | Yes   | Measurement system. The value can be **SI**,&nbsp;**US**, or&nbsp;**UK**.|


## Util<sup>8+</sup>


### unitConvert<sup>8+</sup>

static unitConvert(fromUnit: UnitInfo, toUnit: UnitInfo, value: number, locale: string, style?: string): string

Converts one measurement unit into another and formats the unit based on the specified locale and style.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name     | Type                    | Mandatory  | Description                                      |
| -------- | ---------------------- | ---- | ---------------------------------------- |
| fromUnit | [UnitInfo](#unitinfo8) | Yes   | Measurement unit to be converted.                                |
| toUnit   | [UnitInfo](#unitinfo8) | Yes   | Measurement unit to be converted to.                                |
| value    | number                 | Yes   | Value of the measurement unit to be converted.                            |
| locale   | string                 | Yes   | Locale used for formatting, for example, **zh-Hans-CN**.               |
| style    | string                 | No   | Style used for formatting. The value can be **long**, **short**, or **narrow**.|

**Return value**
| Type    | Description                     |
| ------ | ----------------------- |
| string | Character string obtained after formatting based on the measurement unit specified by **toUnit**.|

**Example**
  ```
  i18n.Util.unitConvert({unit: "cup", measureSystem: "US"}, {unit: "liter", measureSystem: "SI"}, 1000, "en-US", "long");
  ```


## getInstance<sup>8+</sup>

getInstance(locale?:string): IndexUtil

Creates an **IndexUtil** object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description                          |
| ------ | ------ | ---- | ---------------------------- |
| locale | string | No   | A string containing locale information, including the language, optional script, and region.|

**Return value**
| Type                      | Description                   |
| ------------------------ | --------------------- |
| [IndexUtil](#indexutil8) | **IndexUtil** object mapping to the specified locale.|

**Example**
  ```
  var indexUtil= i18n.getInstance("zh-CN");
  ```


## IndexUtil<sup>8+</sup>


### getIndexList<sup>8+</sup>

getIndexList(): Array&lt;string&gt;

Obtains the index list for this **locale** object.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type                 | Description                |
| ------------------- | ------------------ |
| Array&lt;string&gt; | Index list for this **locale** object.|

**Example**
  ```
  var indexUtil = i18n.getInstance("zh-CN");
  var indexList = indexUtil.getIndexList();
  ```


### addLocale<sup>8+</sup>

addLocale(locale: string): void

Adds the index of the new **locale** object to the index list.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description                          |
| ------ | ------ | ---- | ---------------------------- |
| locale | string | Yes   | A string containing locale information, including the language, optional script, and region.|

**Example**
  ```
  var indexUtil = i18n.getInstance("zh-CN");
  indexUtil.addLocale("en-US");
  ```


### getIndex<sup>8+</sup>

getIndex(text: string): string

Obtains the index of a text object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description          |
| ---- | ------ | ---- | ------------ |
| text | string | Yes   | **text** object whose index is to be obtained.|

**Return value**
| Type    | Description         |
| ------ | ----------- |
| string | Index of the **text** object.|

**Example**
  ```
  var indexUtil= i18n.getInstance("zh-CN");
  indexUtil.getIndex("hi"); // Return h.
  ```


## Character<sup>8+</sup>


### isDigit<sup>8+</sup>

static isDigit(char: string): boolean

Checks whether the input character string is composed of digits.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                  |
| ------- | ------------------------------------ |
| boolean | Returns **true** if the input character is a digit; returns **false** otherwise.|

**Example**
  ```
  var isdigit = i18n.Character.isDigit("1"); // Return true.
  ```


### isSpaceChar<sup>8+</sup>

static isSpaceChar(char: string): boolean

Checks whether the input character is a space.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                    |
| ------- | -------------------------------------- |
| boolean | Returns **true** if the input character is a space; returns **false** otherwise.|

**Example**
  ```
  var isspacechar = i18n.Character.isSpaceChar("a"); // Return false.
  ```


### isWhitespace<sup>8+</sup>

static isWhitespace(char: string): boolean

Checks whether the input character is a white space.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                    |
| ------- | -------------------------------------- |
| boolean | Returns **true** if the input character is a white space; returns **false** otherwise.|

**Example**
  ```
  var isspacechar = i18n.Character.isSpaceChar("a"); // Return false.
  ```


### isRTL<sup>8+</sup>

static isRTL(char: string): boolean

Checks whether the input character is of the right to left (RTL) language.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the input character is of the RTL language; returns **false** otherwise.|

**Example**
  ```
  var isrtl = i18n.Character.isRTL("a"); // Return false.
  ```


### isIdeograph<sup>8+</sup>

static isIdeograph(char: string): boolean

Checks whether the input character is an ideographic character.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the input character is an ideographic character; returns **false** otherwise.|

**Example**
  ```
  var isideograph = i18n.Character.isIdeograph("a"); // Return false.
  ```


### isLetter<sup>8+</sup>

static isLetter(char: string): boolean

Checks whether the input character is a letter.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                  |
| ------- | ------------------------------------ |
| boolean | Returns **true** if the input character is a letter; returns **false** otherwise.|

**Example**
  ```
  var isletter = i18n.Character.isLetter("a"); // Return true.
  ```


### isLowerCase<sup>8+</sup>

static isLowerCase(char: string): boolean

Checks whether the input character is a lowercase letter.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the input character is a lowercase letter; returns **false** otherwise.|

**Example**
  ```
  var islowercase = i18n.Character.isLowerCase("a"); // Return true.
  ```


### isUpperCase<sup>8+</sup>

static isUpperCase(char: string): boolean

Checks whether the input character is an uppercase letter.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the input character is an uppercase letter; returns **false** otherwise.|

**Example**
  ```
  var isuppercase = i18n.Character.isUpperCase("a"); // Return false.
  ```


### getType<sup>8+</sup>

static getType(char: string): string

Obtains the type of the input character string.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description   |
| ---- | ------ | ---- | ----- |
| char | string | Yes   | Input character.|

**Return value**
| Type    | Description         |
| ------ | ----------- |
| string | Type of the input character.|

**Example**
  ```
  var type = i18n.Character.getType("a");
  ```


## i18n.getLineInstance<sup>8+</sup>

getLineInstance(locale: string): BreakIterator

Obtains a [BreakIterator](#breakiterator8) object for text segmentation.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description                                      |
| ------ | ------ | ---- | ---------------------------------------- |
| locale | string | Yes   | Valid locale value, for example, **zh-Hans-CN**. The [BreakIterator](#breakiterator8) object segments text according to the rules of the specified locale.|

**Return value**
| Type                              | Description         |
| -------------------------------- | ----------- |
| [BreakIterator](#breakiterator8) | [BreakIterator](#breakiterator8) object used for text segmentation.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  ```


## BreakIterator<sup>8+</sup>


### setLineBreakText<sup>8+</sup>

setLineBreakText(text: string): void

Sets the text to be processed by the [BreakIterator](#breakiterator8) object.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name | Type    | Mandatory  | Description                     |
| ---- | ------ | ---- | ----------------------- |
| text | string | Yes   | Text to be processed by the **BreakIterator** object.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  ```


### getLineBreakText<sup>8+</sup>

getLineBreakText(): string

Obtains the text being processed by the [BreakIterator](#breakiterator8) object.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                    |
| ------ | ---------------------- |
| string | Text being processed by the **BreakIterator** object.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.getLineBreakText(); // Apple is my favorite fruit.
  ```


### current<sup>8+</sup>

current(): number

Obtains the position of the [BreakIterator](#breakiterator8) object in the text being processed.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                         |
| ------ | --------------------------- |
| number | Position of the **BreakIterator** object in the text being processed.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.current(); // 0
  ```


### first<sup>8+</sup>

first(): number

Puts the [BreakIterator](#breakiterator8) object to the first text boundary, which is always at the beginning of the processed text.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description               |
| ------ | ----------------- |
| number | Offset to the first text boundary of the processed text.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.first(); // 0
  ```


### last<sup>8+</sup>

last(): number

Puts the [BreakIterator](#breakiterator8) object to the last text boundary, which is always the next position after the end of the processed text.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                |
| ------ | ------------------ |
| number | Offset of the last text boundary of the processed text.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.last(); // 27
  ```


### next<sup>8+</sup>

next(index?: number): number

Moves the [BreakIterator](#breakiterator8) object backward by the specified number of text boundaries if the specified index is a positive number. If the index is a negative number, the [BreakIterator](#breakiterator8) object will be moved forward by the corresponding number of text boundaries. If no index is specified, the index will be treated as **1**.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name  | Type    | Mandatory  | Description                                      |
| ----- | ------ | ---- | ---------------------------------------- |
| index | number | No   | Number of text boundaries by which the [BreakIterator](#breakiterator8) object is moved. A positive value indicates that the text boundary is moved backward, and a negative value indicates the opposite. If no index is specified, the index will be treated as **1**.|

**Return value**
| Type    | Description                                      |
| ------ | ---------------------------------------- |
| number | Position of the [BreakIterator](#breakiterator8) object in the text after it is moved by the specified number of text boundaries. The value **-1** is returned if the position of the [BreakIterator](#breakiterator8) object is outside of the processed text after it is moved by the specified number of text boundaries.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.first(); // 0
  iterator.next(); // 6
  iterator.next(10); // -1
  ```


### previous<sup>8+</sup>

previous(): number

Moves the [BreakIterator](#breakiterator8) object to the previous text boundary.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                                      |
| ------ | ---------------------------------------- |
| number | Position of the [BreakIterator](#breakiterator8) object in the text after it is moved to the previous text boundary. The value **-1** is returned if the position of the [BreakIterator](#breakiterator8) object is outside of the processed text after it is moved by the specified number of text boundaries.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.first(); // 0
  iterator.next(3); // 12
  iterator.previous(); // 9
  ```


### following<sup>8+</sup>

following(offset: number): number

Moves the [BreakIterator](#breakiterator8) object to the text boundary after the position specified by the offset. Position of the [BreakIterator](#breakiterator8) object after it is moved to the text boundary after the position specified by the offset.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description                                      |
| ------ | ------ | ---- | ---------------------------------------- |
| offset | number | Yes   | Offset to the position before the text boundary to which the [BreakIterator](#breakiterator8) object is moved.|

**Return value**
| Type    | Description                                      |
| ------ | ---------------------------------------- |
| number | The value **-1** is returned if the text boundary to which the [BreakIterator](#breakiterator8) object is moved is outside of the processed text.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.following(0); // 6
  iterator.following(100); // -1
  iterator.current(); // 27
  ```


### isBoundary<sup>8+</sup>

isBoundary(offset: number): boolean

Checks whether the position specified by the offset is a text boundary. If **true** is returned, the [BreakIterator](#breakiterator8) object is moved to the position specified by the offset. If **false** is returned, the [BreakIterator](#breakiterator8) object is moved to the text boundary after the position specified by the offset, which is equivalent to calling [following](#following8)(offset).

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description         |
| ------ | ------ | ---- | ----------- |
| offset | number | Yes   | Position to check.|

**Return value**
| Type     | Description                             |
| ------- | ------------------------------- |
| boolean | Returns **true** if the position specified by the offset is a text boundary; returns **false** otherwise.|

**Example**
  ```
  var iterator = i18n.getLineInstance("en");
  iterator.setLineBreakText("Apple is my favorite fruit.");
  iterator.isBoundary(0); // true;
  iterator.isBoundary(5); // false;
  ```


## i18n.is24HourClock<sup>7+</sup>

is24HourClock(): boolean

Checks whether the 24-hour clock is used.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type     | Description                                      |
| ------- | ---------------------------------------- |
| boolean | Returns **true** if the 24-hour clock is used; returns **false** otherwise.|

**Example**
  ```
  var is24HourClock = i18n.is24HourClock();
  ```


## i18n.set24HourClock<sup>7+</sup>

set24HourClock(option: boolean): boolean

Sets the 24-hour clock.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type     | Mandatory  | Description                                      |
| ------ | ------- | ---- | ---------------------------------------- |
| option | boolean | Yes   | Whether to enable the 24-hour clock. The value **true** means to enable the 24-hour clock, and the value **false** means the opposite.|

**Return value**
| Type     | Description                           |
| ------- | ----------------------------- |
| boolean | Returns **true** if the 24-hour clock is enabled; returns **false** otherwise.|

**Example**
  ```
  // Set the system time to the 24-hour clock.
  var success = i18n.set24HourClock(true);
  ```


## i18n.addPreferredLanguage<sup>8+</sup>

addPreferredLanguage(language: string, index?: number): boolean

Adds a preferred language to the specified position on the preferred language list.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name     | Type    | Mandatory  | Description        |
| -------- | ------ | ---- | ---------- |
| language | string | Yes   | Preferred language to add. |
| index    | number | No   | Position to which the preferred language is added.|

**Return value**
| Type     | Description                           |
| ------- | ----------------------------- |
| boolean | Returns **true** if the preferred language is successfully added; returns **false** otherwise.|

**Example**
  ```
  // Add zh-CN to the preferred language list.
  var language = 'zh-CN';
  var index = 0;
  var success = i18n.addPreferredLanguage(language, index);
  ```


## i18n.removePreferredLanguage<sup>8+</sup>

removePreferredLanguage(index: number): boolean

Deletes a preferred language from the specified position on the preferred language list.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name  | Type    | Mandatory  | Description                   |
| ----- | ------ | ---- | --------------------- |
| index | number | Yes   | Position of the preferred language to delete.|

**Return value**
| Type     | Description                           |
| ------- | ----------------------------- |
| boolean | Returns **true** if the preferred language is deleted; returns **false** otherwise.|

**Example**
  ```
  // Delete the first preferred language from the preferred language list.
  var index = 0;
  var success = i18n.removePreferredLanguage(index);
  ```


## i18n.getPreferredLanguageList<sup>8+</sup>

getPreferredLanguageList(): Array&lt;string&gt;

Obtains the list of preferred languages.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type                 | Description       |
| ------------------- | --------- |
| Array&lt;string&gt; | List of preferred languages.|

**Example**
  ```
  var preferredLanguageList = i18n.getPreferredLanguageList();
  ```


## i18n.getFirstPreferredLanguage<sup>8+</sup>

getFirstPreferredLanguage(): string

Obtains the first language in the preferred language list.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description            |
| ------ | -------------- |
| string | First language in the preferred language list.|

**Example**
  ```
  var firstPreferredLanguage = i18n.getFirstPreferredLanguage();
  ```


## i18n.getAppPreferredLanguage<sup>9+</sup>

getAppPreferredLanguage(): string

Obtains the preferred language of an application.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description            |
| ------ | -------------- |
| string | Preferred language of the application.|

**Example**
  ```
  var appPreferredLanguage = i18n.getAppPreferredLanguage();
  ```


## i18n.getTimeZone<sup>7+</sup>

getTimeZone(zoneID?: string): TimeZone

Obtains the **TimeZone** object corresponding to the specified time zone ID.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description   |
| ------ | ------ | ---- | ----- |
| zondID | string | No   | Time zone ID.|

**Return value**
| Type      | Description          |
| -------- | ------------ |
| TimeZone | **TimeZone** object corresponding to the time zone ID.|

**Example**
  ```
  var timezone = i18n.getTimeZone();
  ```


## TimeZone<sup>8+</sup>


### getID<sup>8+</sup>

getID(): string

Obtains the ID of the specified **TimeZone** object.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description          |
| ------ | ------------ |
| string | Time zone ID corresponding to the **TimeZone** object.|

**Example**
  ```
  var timezone = i18n.getTimeZone();
  timezone.getID();
  ```


### getDisplayName<sup>8+</sup>

getDisplayName(locale?: string, isDST?: boolean): string

Obtains the representation of a **TimeZone** object in the specified locale.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type     | Mandatory  | Description                  |
| ------ | ------- | ---- | -------------------- |
| locale | string  | No   | System locale ID.               |
| isDST  | boolean | No   | Whether to consider DST when obtaining the representation of the **TimeZone** object.|

**Return value**
| Type    | Description           |
| ------ | ------------- |
| string | Representation of the **TimeZone** object in the specified locale.|

**Example**
  ```
  var timezone = i18n.getTimeZone();
  timezone.getDisplayName("zh-CN", false);
  ```


### getRawOffset<sup>8+</sup>

getRawOffset(): number

Obtains the offset between the time zone represented by a **TimeZone** object and the UTC time zone.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                 |
| ------ | ------------------- |
| number | Offset between the time zone represented by the **TimeZone** object and the UTC time zone.|

**Example**
  ```
  var timezone = i18n.getTimeZone();
  timezone.getRawOffset();
  ```


### getOffset<sup>8+</sup>

getOffset(date?: number): number

Obtains the offset between the time zone represented by a **TimeZone** object and the UTC time zone at a certain time point.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                     |
| ------ | ----------------------- |
| number | Offset between the time zone represented by the **TimeZone** object and the UTC time zone at a certain time point.|

**Example**
  ```
  var timezone = i18n.getTimeZone();
  timezone.getOffset(1234567890);
  ```

### getAvailableIDs<sup>9+</sup>

static getAvailableIDs(): Array&lt;string&gt;

Obtains the list of time zone IDs supported by the system.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                      |
| ------ | ----------------------- |
| Array&lt;string&gt; | List of time zone IDs supported by the system.|

**Example**
  ```
  var ids = i18n.TimeZone.getAvailableIDs();
  ```


### getAvailableZoneCityIDs<sup>9+</sup>

static getAvailableZoneCityIDs(): Array&lt;string&gt;

Obtains the list of time zone city IDs supported by the system.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type    | Description                      |
| ------ | ----------------------- |
| Array&lt;string&gt; | List of time zone city IDs supported by the system.|

**Example**
  ```
  var cityIDs = i18n.TimeZone.getAvailableZoneCityIDs();
  ```


### getCityDisplayName<sup>9+</sup>

static getCityDisplayName(cityID: string, locale: string): string

Obtains the localized display of a time zone city in the specified locale.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description   |
| ------ | ------ | ---- | ----- |
| cityID | string | Yes   | Time zone city ID.|
| locale | string | Yes   | Locale ID.|

**Return value**
| Type    | Description                     |
| ------ | ----------------------- |
| string | Localized display of the time zone city in the specified locale.|

**Example**
  ```
  var displayName = i18n.TimeZone.getCityDisplayName("Shanghai", "zh-CN");
  ```


### getTimezoneFromCity<sup>9+</sup>

static getTimezoneFromCity(cityID: string): TimeZone

Obtains the **TimeZone** object corresponding to the specified time zone city ID.

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description   |
| ------ | ------ | ---- | ----- |
| cityID | string | Yes   | Time zone city ID.|

**Return value**
| Type    | Description                     |
| ------ | ----------------------- |
| TimeZone | **TimeZone** object corresponding to the specified time zone city ID.|

**Example**
  ```
  var timezone = i18n.TimeZone.getTimezoneFromCity("Shanghai");
  ```


## i18n.setUsingLocalDigit<sup>9+</sup>

setUsingLocalDigit(flag: boolean): boolean

Sets whether to turn on the local digit switch.
This is a system API.

**Permission required**: ohos.permission.UPDATE_CONFIGURATION

**System capability**: SystemCapability.Global.I18n

**Parameters**
| Name   | Type    | Mandatory  | Description   |
| ------ | ------ | ---- | ----- |
| flag | boolean | Yes   | Whether to turn on the local digit switch. The value **true** means to turn on the local digit switch, and the value **false** indicates the opposite.|

**Return value**
| Type      | Description          |
| -------- | ------------ |
| boolean | Result indicating whether the local digit switch is successfully set. The value **true** indicates that the local digit switch is successfully set, and the value **false** indicates the opposite.|

**Example**
  ```
  var status = i18n.setUsingLocalDigit(true);
  ```


## i18n.getUsingLocalDigit<sup>9+</sup>

getUsingLocalDigit(): boolean

Checks whether the local digit switch is turned on.

**System capability**: SystemCapability.Global.I18n

**Return value**
| Type      | Description          |
| -------- | ------------ |
| boolean | Result indicating whether the local digit switch is turned on. The value **true** indicates that the local digit switch is turned on, and the value **false** indicates the opposite.|

**Example**
  ```
  var status = i18n.getUsingLocalDigit();
  ```