GeoJSON

• GeoJSON 是一种用于表达地理数据的 JSON，即是 JSON 的一种特定形式。
• GeoJSON 定义了七种几何类型来表达地理要素，分别是（大小写敏感）
  • Point
  • MultiPoint
  • LineString
  • MultiLineString
  • Polygon
  • MultiPolygon
  • GeometryCollection

可以参考 geojson.io 来动态生成 GeoJSON。

GeoJSON 总体就是地理几何数据的集合，每一个几何数据就是一个 Feature，一个 GeoJSON 就是一个 FeatureCollection。例如下边就是一个 GeoJSON 的样例：

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "type": "Polygon",
        "coordinates": [
          [
            [
              113.983154296875,
              22.507482299898438
            ],
            [
              114.488525390625,
              22.507482299898438
            ],
            [
              114.488525390625,
              22.659640758754797
            ],
            [
              113.983154296875,
              22.659640758754797
            ],
            [
              113.983154296875,
              22.507482299898438
            ]
          ]
        ]
      }
    },
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "type": "Point",
        "coordinates": [
          113.26904296874999,
          23.150462029224087
        ]
      }
    },
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "type": "LineString",
        "coordinates": [
          [
            113.65905761718749,
            23.054461926693815
          ],
          [
            113.84033203125,
            23.024131861805987
          ],
          [
            113.9556884765625,
            23.049407390110577
          ]
        ]
      }
    },
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "type": "Polygon",
        "coordinates": [
          [
            [
              113.7249755859375,
              22.867317960075614
            ],
            [
              113.851318359375,
              22.786310789104277
            ],
            [
              113.97216796875,
              22.85213278864118
            ],
            [
              113.9337158203125,
              22.948276856880895
            ],
            [
              113.7249755859375,
              22.867317960075614
            ]
          ]
        ]
      }
    }
  ]
}