19596a2c1Sopenharmony_ci# i18n<a name="EN-US_TOPIC_0000001101364976"></a> 29596a2c1Sopenharmony_ci 39596a2c1Sopenharmony_ci- [Introduction](#section11660541593) 49596a2c1Sopenharmony_ci- [Directory Structure](#section1464106163817) 59596a2c1Sopenharmony_ci- [Constraints](#section1718733212019) 69596a2c1Sopenharmony_ci- [Usage](#section894511013511) 79596a2c1Sopenharmony_ci- [Repositories Involved](#section15583142420413) 89596a2c1Sopenharmony_ci 99596a2c1Sopenharmony_ci## Introduction<a name="section11660541593"></a> 109596a2c1Sopenharmony_ci 119596a2c1Sopenharmony_ciThe i18n module provides a wide array of internationalization \(i18n\) APIs for implementing functions such as date and time formatting. 129596a2c1Sopenharmony_ci 139596a2c1Sopenharmony_ci## Directory Structure<a name="section1464106163817"></a> 149596a2c1Sopenharmony_ci 159596a2c1Sopenharmony_ciThe directory structure for the i18n module is as follows: 169596a2c1Sopenharmony_ci 179596a2c1Sopenharmony_ci``` 189596a2c1Sopenharmony_ci/base/global/ 199596a2c1Sopenharmony_ci├── i18n # Code repository for the i18n framework 209596a2c1Sopenharmony_ci│ ├── frameworks # Core code of the i18n framework 219596a2c1Sopenharmony_ci│ ├── interfaces # APIs 229596a2c1Sopenharmony_ci│ │ ├── js # JavaScript APIs 239596a2c1Sopenharmony_ci│ │ └── native # Native APIs 249596a2c1Sopenharmony_ci``` 259596a2c1Sopenharmony_ci 269596a2c1Sopenharmony_ci## Constraints<a name="section1718733212019"></a> 279596a2c1Sopenharmony_ci 289596a2c1Sopenharmony_ci**Development language**: JavaScript 299596a2c1Sopenharmony_ci 309596a2c1Sopenharmony_ci**Language, script, and country codes**: The supported language must be represented by a two- or three-letter code defined in the ISO 639 standard; the supported script must be represented by a four-letter code defined in the ISO 15924 standard; the supported country must be represented by a two-letter code defined in the ISO 3166 standard. 319596a2c1Sopenharmony_ci 329596a2c1Sopenharmony_ci## Usage<a name="section894511013511"></a> 339596a2c1Sopenharmony_ci 349596a2c1Sopenharmony_ciChange the date and time formats \(such as the sequence of year, month, and day, month and week names, and 12-hour or 24-hour system\) following the system settings to adapt to the cultural habits of users in different locales. For details, see the API reference. The sample code is as follows: 359596a2c1Sopenharmony_ci 369596a2c1Sopenharmony_ci``` 379596a2c1Sopenharmony_ciconst date = new Date(2021, 11, 17, 3, 24, 0); // Create a Date object containing date and time information. 389596a2c1Sopenharmony_cifmt = new Intl.DateTimeFormat('en-US') // Create a DateTimeFormat instance. 399596a2c1Sopenharmony_ciconsole.log(fmt.format(date)); // Format the date and time by using the DateTimeFormat instance. 409596a2c1Sopenharmony_ci``` 419596a2c1Sopenharmony_ci 429596a2c1Sopenharmony_ci## Repositories Involved<a name="section15583142420413"></a> 439596a2c1Sopenharmony_ci 449596a2c1Sopenharmony_ciGlobalization subsystem 459596a2c1Sopenharmony_ci 469596a2c1Sopenharmony_ci**global\_i18n\_standard** 479596a2c1Sopenharmony_ci 489596a2c1Sopenharmony_ciglobal\_resmgr\_standard 499596a2c1Sopenharmony_ci 50