我有dxf格式的以下CAD文件，它以autocad显示，如下所示：

我用gdalorg2org将它转换成geojson格式的文件，名为test.geojson，但都是type: LineString{

"type": "FeatureCollection",

"name": "entities",

"features": [

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 30.0, 0.0 ], [ 30.0, 9.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 16.0, 47.0 ], [ 16.0, 34.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 16.0, 13.0 ], [ 16.0, 0.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 0.0, 31.0 ], [ 9.0, 31.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 30.0, 31.0 ], [ 39.0, 31.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 0.0, 23.0 ], [ 9.0, 23.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 30.0, 23.0 ], [ 39.0, 23.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 0.0, 16.0 ], [ 9.0, 16.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 30.0, 16.0 ], [ 39.0, 16.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 0.0, 0.0 ], [ 39.0, 0.0 ], [ 39.0, 47.0 ], [ 0.0, 47.0 ], [ 0.0, 0.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 9.0, 38.0 ], [ 11.0, 38.0 ], [ 11.0, 34.0 ], [ 28.0, 34.0 ], [ 28.0, 38.0 ], [ 30.0, 38.0 ], [ 30.0, 9.0 ], [ 28.0, 9.0 ], [ 28.0, 13.0 ], [ 11.0, 13.0 ], [ 11.0, 9.0 ], [ 9.0, 9.0 ], [ 9.0, 38.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 11.0, 32.0 ], [ 17.0, 32.0 ], [ 17.0, 15.0 ], [ 11.0, 15.0 ], [ 11.0, 32.0 ] ] } },

{ "type": "Feature", "properties": { "Layer": "0" }, "geometry": { "type": "LineString", "coordinates": [ [ 20.0, 32.0 ], [ 28.0, 32.0 ], [ 28.0, 15.0 ], [ 20.0, 15.0 ], [ 20.0, 32.0 ] ] } }

]

}

我想把它转换成type: polygon，显示如下图：

在地质公园我怎么能做到呢？谢谢。在

顺便说一句，我读了test.geojson文件，它看起来像：

^{pr2}$

输出：Layer SubClasses EntityHandle geometry

0 0 AcDbEntity:AcDbPolyline 106 LINESTRING (30.35270412013777 0.79246615687498...

1 0 AcDbEntity:AcDbPolyline 107 LINESTRING (16.16520412013776 47.1049661568749...

2 0 AcDbEntity:AcDbPolyline 108 LINESTRING (16.16520412013776 13.4799661568749...

3 0 AcDbEntity:AcDbPolyline 109 LINESTRING (0.665204120137787 31.2924661568749...

4 0 AcDbEntity:AcDbPolyline 10A LINESTRING (30.35270412013777 31.2924661568749...