Swift GeoJson解析 [英] Swift GeoJson Parse

问题描述

{
  "type": "Feature",
  "geometry": {
    "type": "Point",
    "coordinates": [
      126.9823439963945,
      37.56461982743129
    ]
  }
},
{
  "type": "Feature",
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [
        126.9823439963945,
        37.56461982743129
      ],
      [
        126.98230789017299,
        37.564453179812105
      ],
      [
        126.98210513804034,
        37.563703265276516
      ],
      [
        126.98207180945346,
        37.56352550784786
      ],
      [
        126.9817857308457,
        37.56284502921221
      ],
      [
        126.98166907678578,
        37.562633941789535
      ],
      [
        126.98157186492477,
        37.56247284870586
      ],
      [
        126.98128300624569,
        37.56205345097403
      ],
      [
        126.98124689891416,
        37.56200067907546
      ]
    ],
    "traffic": [0, 8, 4, 12]
  }}

这就是我得到的.而且我不知道解析关键的坐标".此类型取决于几何类型.如果类型是点"，则类型变为[字符串].如果类型是"LineString"，则类型变为[[String]].我该怎么解决?

This is what I got. And I don't have any idea to parse key "coordinates". This type depends on type of geometry. If type is "Point", type became [String]. If type is "LineString", type became [[String]]. How can I solve it?

推荐答案

您可以使用以下可可豆荚: CodableGeoJSON .

You can use this cocoa pod: CodableGeoJSON.

它具有为您编写的 Codable 结构.您似乎在这里具有未知几何的特征，因此可以执行以下操作:

It has the Codable structs written up for you. You seem to have a feature with an unknown geometry here, so you can do something like this:

let geoJSON = try JSONDecoder().decode(GeoJSON.self, from: geoJSONData)
guard case .feature(let feature) = geoJSON else {
    // the GeoJSON does not contain a feature!
}

// handle each kind of geometry...
switch feature.geometry {
case .point(let coordinates): // coordinates is a GeoJSONPosition
    // ...
case .multiPoint(let coordinates): // coordinates is a [GeoJSONPosition]
    // ...
case .lineString(let coordinates): // coordinates is a [GeoJSONPosition]
    // ...
case .multiLineString(let coordinates): // coordinates is a [[GeoJSONPosition]]
    // ...
case .polygon(let coordinates): // coordinates is a [[GeoJSONPosition]]
    // ...
case .multiPolygon(let coordinates): // coordinates is a [[[GeoJSONPosition]]]
    // ...
case .geometryCollection(let geometries):
    // ...
}

如果您不喜欢为此使用库，请查看其源代码并尝试从中学习，特别是

If you don't like using a library just for this, have a look at their source code and try to learn from it, specifically, GeoJSON.swift.

这篇关于Swift GeoJson解析的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！