geojson-to-wkt 坐标格式转换

geojson-to-wkt 坐标格式转换

一个 简单、轻量、健壮 的 JavaScript / TypeScript 库，用于将 GeoJSON 数据转换为 WKT（Well-Known Text） 格式。

本库面向 真实 GIS / 数据库场景 设计，适用于将前端或服务端的 GeoJSON 数据输出为数据库可直接使用的 WKT。

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特性

• 🚀 轻量、无依赖
• 🧠 明确的几何类型映射（非字符串拼接）
• 🧩 支持 GeoJSON Geometry / Feature / FeatureCollection
• 📐 支持 Z / M 坐标（XY / XYZ / XYM / XYZM）
• 🗄 输出数据库标准 WKT
• 🌲 Tree Shaking 友好，支持按需引入

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安装

pnpm install @giszhc/geojson-to-wkt

或

npm install @giszhc/geojson-to-wkt

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支持的类型映射

GeoJSON 类型	WKT 类型
Point	POINT
MultiPoint	MULTIPOINT
LineString	LINESTRING
MultiLineString	MULTILINESTRING
Polygon	POLYGON
MultiPolygon	MULTIPOLYGON
GeometryCollection	GEOMETRYCOLLECTION
Feature	对应 Geometry
FeatureCollection	GEOMETRYCOLLECTION

---

API

geometryToWKT(geometry: Geometry): string

将 GeoJSON Geometry 转换为 WKT 字符串

import { geometryToWKT } from '@giszhc/geojson-to-wkt';

const geometry = {
  type: 'Point',
  coordinates: [120, 30]
};

geometryToWKT(geometry);
// "POINT (120 30)"

---

featureToWKT(feature: Feature): string

将 GeoJSON Feature 转换为 WKT

Feature 的 properties 会被忽略，仅处理 geometry

import { featureToWKT } from '@giszhc/geojson-to-wkt';

const feature = {
  type: 'Feature',
  geometry: {
    type: 'Point',
    coordinates: [120, 30]
  },
  properties: {}
};

featureToWKT(feature);
// "POINT (120 30)"

---

featureCollectionToWKT(featureCollection: FeatureCollection): string

将 GeoJSON FeatureCollection 转换为 GEOMETRYCOLLECTION WKT

import { featureCollectionToWKT } from '@giszhc/geojson-to-wkt';

const collection = {
  type: 'FeatureCollection',
  features: [
    {
      type: 'Feature',
      geometry: {
        type: 'Point',
        coordinates: [120, 30]
      },
      properties: {}
    },
    {
      type: 'Feature',
      geometry: {
        type: 'LineString',
        coordinates: [[120, 30], [121, 31]]
      },
      properties: {}
    }
  ]
};

featureCollectionToWKT(collection);
// "GEOMETRYCOLLECTION (POINT (120 30), LINESTRING (120 30, 121 31))"

---

toWKT(input: GeoJSON): string

通用转换方法，自动识别输入类型

支持：

• Geometry
• Feature
• FeatureCollection

import { toWKT } from '@giszhc/geojson-to-wkt';

toWKT({
  type: 'Point',
  coordinates: [120, 30]
});
// "POINT (120 30)"

toWKT({
  type: 'Feature',
  geometry: {
    type: 'LineString',
    coordinates: [[120, 30], [121, 31]]
  }
});
// "LINESTRING (120 30, 121 31)"

---

Multi* 几何示例

MultiPoint

geometryToWKT({
  type: 'MultiPoint',
  coordinates: [
    [10, 10],
    [20, 20]
  ]
});
// "MULTIPOINT (10 10, 20 20)"

MultiLineString

geometryToWKT({
  type: 'MultiLineString',
  coordinates: [
    [[10, 10], [20, 20]],
    [[30, 30], [40, 40]]
  ]
});
// "MULTILINESTRING ((10 10, 20 20), (30 30, 40 40))"

MultiPolygon

geometryToWKT({
  type: 'MultiPolygon',
  coordinates: [
    [[[0, 0], [10, 0], [10, 10], [0, 0]]]
  ]
});
// "MULTIPOLYGON (((0 0, 10 0, 10 10, 0 0)))"

---

GeometryCollection

geometryToWKT({
  type: 'GeometryCollection',
  geometries: [
    {
      type: 'Point',
      coordinates: [10, 10]
    },
    {
      type: 'LineString',
      coordinates: [[20, 20], [30, 30]]
    }
  ]
});
GEOMETRYCOLLECTION (POINT (10 10), LINESTRING (20 20, 30 30))

---

Z / M 坐标支持

geometryToWKT({
  type: 'Point',
  coordinates: [10, 10, 5]
});
// "POINT (10 10 5)"
geometryToWKT({
  type: 'Point',
  coordinates: [10, 10, 5, 7]
});
// "POINT (10 10 5 7)"

---

推荐测试用例

const cases = [
  {
    type: 'Point',
    coordinates: [10, 10]
  },
  {
    type: 'MultiPoint',
    coordinates: [[10, 10], [20, 20]]
  },
  {
    type: 'LineString',
    coordinates: [[10, 10], [20, 20]]
  },
  {
    type: 'Polygon',
    coordinates: [[[0, 0], [10, 0], [10, 10], [0, 0]]]
  },
  {
    type: 'GeometryCollection',
    geometries: [
      { type: 'Point', coordinates: [1, 1] },
      { type: 'LineString', coordinates: [[0, 0], [1, 1]] }
    ]
  }
];

cases.forEach(geojson => {
  expect(() => toWKT(geojson as any)).not.toThrow();
});

---

注意事项

• 输出格式遵循数据库标准：TYPE (x y, ...)
• 不自动添加 SRID
• 不修改原始坐标维度与顺序
• Feature.properties 不参与转换

完结，撒花✿✿ヽ(°▽°)ノ✿