enumerate

import { listProvinces, listAmphures, listTambons } from 'thaizip'

None of these three functions take a text query. They’re for building cascade dropdowns (province → district → subdistrict), backed by the byProvince/byAmphure groupings precomputed when the index was built — no full scan of records on every call.

listProvinces

function listProvinces(index: TrigramIndex): ProvinceSummary[]

Parameters

Name	Type	Default	Description
index	TrigramIndex	— (required)	The index to list provinces from

Returns

ProvinceSummary[] — all 77 provinces (in the bundled default dataset), deduplicated, sorted by Thai name with Intl.Collator('th')

type ProvinceSummary = {
  id: number
  nameTh: string
  nameEn: string
}

Example

import { listProvinces } from 'thaizip'

const provinces = listProvinces(index) // 77 provinces, sorted by Thai name

listAmphures

function listAmphures(index: TrigramIndex, provinceId: number): AmphureSummary[]

Parameters

Name	Type	Default	Description
index	TrigramIndex	— (required)	The index to list districts from
provinceId	number	— (required)	A province id (from ProvinceSummary.id)

Returns

AmphureSummary[] — all districts within that province, deduplicated, sorted by Thai name. Returns an empty array [] if provinceId doesn’t exist (e.g. 0 before anything is selected).

type AmphureSummary = {
  id: number
  nameTh: string
  nameEn: string
  provinceId: number
}

Example

import { listAmphures } from 'thaizip'

listAmphures(index, 1) // every district in Bangkok

listTambons

function listTambons(index: TrigramIndex, amphureId: number): TambonSummary[]

Parameters

Name	Type	Default	Description
index	TrigramIndex	— (required)	The index to list subdistricts from
amphureId	number	— (required)	A district id (from AmphureSummary.id)

Returns

TambonSummary[] — all subdistricts within that district, sorted by Thai name, each with its zipCode attached. Returns an empty array [] if amphureId doesn’t exist.

type TambonSummary = {
  id: number
  nameTh: string
  nameEn: string
  amphureId: number
  zipCode: string
}

Example

import { listTambons } from 'thaizip'

listTambons(index, 1001) // every subdistrict in that district, with zipCode

Shared notes

• All three functions always return an empty array [] for an unknown id — never throw — which makes it easy to write UI that resets child selections whenever a parent selection changes
• Each byAmphure entry already maps to exactly one tambon, so listTambons doesn’t need to deduplicate the way listProvinces/listAmphures do
• If the index passed in lacks byProvince/byAmphure (for example, an older-shaped index built by hand), all three functions fall back to scanning index.records in full