/// <summary>
/// Parses the specified <paramref name="json"/> object into an instance deriving from <see cref="GeoJsonObject"/>.
///
/// As the GeoJSON format specified the type of a
/// </summary>
/// <param name="json">The JSON object.</param>
/// <returns>An instance that derives from <see cref="GeoJsonObject"/>.</returns>
private static GeoJsonObject Parse(JObject json)
{
if (json == null)
{
return(null);
}
// Get the value of the "type" property
string type = json.GetString("type");
if (string.IsNullOrWhiteSpace(type))
{
throw new GeoJsonParseException("The JSON object doesn't specify a type", json);
}
// Parse the type into an enum
if (EnumUtils.TryParseEnum(type, out GeoJsonType result) == false)
{
throw new GeoJsonParseException($"Unknown type {type}", json);
}
switch (result)
{
case GeoJsonType.Feature:
return(GeoJsonFeature.Parse(json));
case GeoJsonType.FeatureCollection:
return(GeoJsonFeatureCollection.Parse(json));
case GeoJsonType.Point:
return(GeoJsonPoint.Parse(json));
case GeoJsonType.LineString:
return(GeoJsonLineString.Parse(json));
case GeoJsonType.Polygon:
return(GeoJsonPolygon.Parse(json));
case GeoJsonType.MultiPoint:
return(GeoJsonMultiPoint.Parse(json));
//case GeoJsonType.MultiLineString:
// return GeoJsonMultiLineString.Parse(obj);
case GeoJsonType.MultiPolygon:
return(GeoJsonMultiPolygon.Parse(json));
case GeoJsonType.GeometryCollection:
return(GeoJsonGeometryCollection.Parse(json));
default:
throw new GeoJsonParseException($"Unknown type {type}", json);
}
}
/// <inheritdoc />
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
if (reader.TokenType == JsonToken.Null)
{
return(null);
}
if (reader.TokenType != JsonToken.StartObject)
{
return(null);
}
JObject obj = JObject.Load(reader);
string type = obj.Value <string>("type");
switch (type?.ToLower())
{
case "feature":
return(GeoJsonFeature.Parse(obj));
case "featurecollection":
return(GeoJsonFeatureCollection.Parse(obj));
case "point":
return(GeoJsonPoint.Parse(obj));
case "multipoint":
return(GeoJsonMultiPoint.Parse(obj));
case "linestring":
return(GeoJsonLineString.Parse(obj));
case "multilinestring":
return(GeoJsonMultiLineString.Parse(obj));
case "polygon":
return(GeoJsonPolygon.Parse(obj));
case "multipolygon":
return(GeoJsonMultiPolygon.Parse(obj));
default:
if (objectType == typeof(GeoJsonProperties))
{
return(ReadJsonProperties(reader));
}
throw new GeoJsonParseException($"Unknown shape: {type}", obj);
}
}
public void Parse1()
{
GeoJsonMultiPoint mp = GeoJsonMultiPoint.Parse("{\"type\":\"MultiPoint\",\"coordinates\":[[10.0,40.0],[40.0,30.0],[20.0,20.0],[30.0,10.0]]}");
Assert.AreEqual(4, mp.Count);
GeoJsonCoordinates p1 = mp[0];
GeoJsonCoordinates p2 = mp[1];
GeoJsonCoordinates p3 = mp[2];
GeoJsonCoordinates p4 = mp[3];
Assert.AreEqual(10, p1.X, "#1 X");
Assert.AreEqual(40, p1.Y, "#1 Y");
Assert.AreEqual(40, p2.X, "#2 X");
Assert.AreEqual(30, p2.Y, "#2 Y");
Assert.AreEqual(20, p3.X, "#3 X");
Assert.AreEqual(20, p3.Y, "#3 Y");
Assert.AreEqual(30, p4.X, "#4 X");
Assert.AreEqual(10, p4.Y, "#4 Y");
}