Draw programmatically MultiPolygon

[ProxBiz]

Hello,
I am tryng to create a MultiPolygon with the code bellow

I get the error:
Error: System.Text.Json.JsonException: The JSON value could not be converted to OpenLayers.Blazor.Coordinates. Path: $.coordinates | LineNumber: 0 | BytePositionInLine: 93.
---> System.InvalidOperationException: Cannot get the value of a token type 'EndArray' as a number.

Message=
Source=
StackTrace:
at System.Text.Json.ThrowHelper.ThrowInvalidOperationException_ExpectedNumber(JsonTokenType tokenType)
at System.Text.Json.Utf8JsonReader.TryGetDouble(Double& value)
at OpenLayers.Blazor.CoordinateConverter.Read(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options)
at OpenLayers.Blazor.CoordinatesConverter.Read(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options)
at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Coordinates, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Coordinates& value, Boolean& isPopulatedValue) at System.Text.Json.Serialization.Metadata.JsonPropertyInfo1[[OpenLayers.Blazor.Coordinates, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].ReadJsonAndSetMember(Object obj, ReadStack& state, Utf8JsonReader& reader)
at System.Text.Json.Serialization.Converters.ObjectDefaultConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Shape& value) at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Shape& value, Boolean& isPopulatedValue)
at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].ReadCore(Utf8JsonReader& reader, Shape& value, JsonSerializerOptions options, ReadStack& state) --- End of inner exception stack trace --- at System.Text.Json.ThrowHelper.ReThrowWithPath(ReadStack& state, Utf8JsonReader& reader, Exception ex) at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].ReadCore(Utf8JsonReader& reader, Shape& value, JsonSerializerOptions options, ReadStack& state)
at System.Text.Json.Serialization.Metadata.JsonTypeInfo1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].Deserialize(Utf8JsonReader& reader, ReadStack& state) at System.Text.Json.Serialization.Metadata.JsonTypeInfo1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].DeserializeAsObject(Utf8JsonReader& reader, ReadStack& state)
at System.Text.Json.JsonSerializer.ReadAsObject(Utf8JsonReader& reader, JsonTypeInfo jsonTypeInfo)
at System.Text.Json.JsonSerializer.Deserialize(Utf8JsonReader& reader, Type returnType, JsonSerializerOptions options)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.ParseArguments(JSRuntime jsRuntime, String methodIdentifier, String arguments, Type[] parameterTypes)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.InvokeSynchronously(JSRuntime jsRuntime, DotNetInvocationInfo& callInfo, IDotNetObjectReference objectReference, String argsJson)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.BeginInvokeDotNet(JSRuntime jsRuntime, DotNetInvocationInfo invocationInfo, String argsJson)
at w.endInvokeDotNetFromJS (https://localhost:10441/_framework/blazor.web.js:1:3158)
at Object.zr [as endInvokeDotNetFromJS] (https://localhost:10441/_framework/blazor.web.js:1:165451)
at https://localhost:10441/_framework/dotnet.runtime.18clfjpo0j.js:3:33880
at Fc (https://localhost:10441/_framework/dotnet.runtime.18clfjpo0j.js:3:172344)
at wasm://wasm/00b5d276:wasm-function[288]:0x1f35a
at wasm://wasm/00b5d276:wasm-function[219]:0x1c95a
at wasm://wasm/00b5d276:wasm-function[210]:0xeaaf
at wasm://wasm/00b5d276:wasm-function[247]:0x1d5bb
at wasm://wasm/00b5d276:wasm-function[3224]:0xf168d
at wasm://wasm/00b5d276:wasm-function[2547]:0xc719d

I have also tried to draw a MultiPolygon using the demo and selecting ShapeType ShapeType= ShapeType.MultiPolygon; same error with the Json sparse;

Error: System.Text.Json.JsonException: The JSON value could not be converted to OpenLayers.Blazor.Coordinates. Path: $.coordinates | LineNumber: 0 | BytePositionInLine: 96.
---> System.InvalidOperationException: Cannot get the value of a token type 'Null' as a number.

Message=
Source=
StackTrace:
at System.Text.Json.ThrowHelper.ThrowInvalidOperationException_ExpectedNumber(JsonTokenType tokenType)
at System.Text.Json.Utf8JsonReader.TryGetDouble(Double& value)
at OpenLayers.Blazor.CoordinateConverter.Read(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options)
at OpenLayers.Blazor.CoordinatesConverter.Read(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options)
at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Coordinates, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Coordinates& value, Boolean& isPopulatedValue) at System.Text.Json.Serialization.Metadata.JsonPropertyInfo1[[OpenLayers.Blazor.Coordinates, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].ReadJsonAndSetMember(Object obj, ReadStack& state, Utf8JsonReader& reader)
at System.Text.Json.Serialization.Converters.ObjectDefaultConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Shape& value) at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Shape& value, Boolean& isPopulatedValue)
at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].ReadCore(Utf8JsonReader& reader, Shape& value, JsonSerializerOptions options, ReadStack& state) --- End of inner exception stack trace --- at System.Text.Json.ThrowHelper.ReThrowWithPath(ReadStack& state, Utf8JsonReader& reader, Exception ex) at System.Text.Json.Serialization.JsonConverter1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].ReadCore(Utf8JsonReader& reader, Shape& value, JsonSerializerOptions options, ReadStack& state)
at System.Text.Json.Serialization.Metadata.JsonTypeInfo1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].Deserialize(Utf8JsonReader& reader, ReadStack& state) at System.Text.Json.Serialization.Metadata.JsonTypeInfo1[[OpenLayers.Blazor.Internal.Shape, OpenLayers.Blazor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null]].DeserializeAsObject(Utf8JsonReader& reader, ReadStack& state)
at System.Text.Json.JsonSerializer.ReadAsObject(Utf8JsonReader& reader, JsonTypeInfo jsonTypeInfo)
at System.Text.Json.JsonSerializer.Deserialize(Utf8JsonReader& reader, Type returnType, JsonSerializerOptions options)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.ParseArguments(JSRuntime jsRuntime, String methodIdentifier, String arguments, Type[] parameterTypes)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.InvokeSynchronously(JSRuntime jsRuntime, DotNetInvocationInfo& callInfo, IDotNetObjectReference objectReference, String argsJson)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.BeginInvokeDotNet(JSRuntime jsRuntime, DotNetInvocationInfo invocationInfo, String argsJson)
at w.endInvokeDotNetFromJS (https://localhost:10441/_framework/blazor.web.js:1:3158)
at Object.zr [as endInvokeDotNetFromJS] (https://localhost:10441/_framework/blazor.web.js:1:165451)
at https://localhost:10441/_framework/dotnet.runtime.18clfjpo0j.js:3:33880
at Fc (https://localhost:10441/_framework/dotnet.runtime.18clfjpo0j.js:3:172344)
at wasm://wasm/00b5d276:wasm-function[288]:0x1f35a
at wasm://wasm/00b5d276:wasm-function[219]:0x1c95a
at wasm://wasm/00b5d276:wasm-function[210]:0xeaaf
at wasm://wasm/00b5d276:wasm-function[247]:0x1d5bb
at wasm://wasm/00b5d276:wasm-function[3224]:0xf168d
at wasm://wasm/00b5d276:wasm-function[2547]:0xc719d

Using the same logic for MultiLineString works with no problems

The code:
shape = new Shape(ShapeType.MultiPolygon);
shape.Coordinates.Values.Clear();
shape.Coordinates.Type = CoordinatesType.MultiList;
shape.Coordinates.Values.Add(new List()
{
new Coordinate(25.96191042963997,47.706858355214706),
new Coordinate(25.966889774948257,47.708316026434574),
new Coordinate(25.967701624726786,47.70499976528495),
new Coordinate(25.96191042963997,47.706858355214706)
});
shape.Coordinates.Values.Add(new List() {
new Coordinate(25.96180218300283,47.71141344241963),
new Coordinate(25.974034052999286,47.70656681607872),
new Coordinate(25.96851347450531,47.70219353335824),
new Coordinate(25.95714757760595,47.70645748848236),
new Coordinate(25.96180218300283,47.71141344241963)
});

 shape.Fill = "#563d7c";
 shape.Stroke = "#dd1111";
 shape.StrokeThickness = 2;
 shape.Id = Guid.NewGuid().ToString();
 refLayer.ShapesList.Add(shape);

Can you help me with the problem or poin me in the right direction.

[lolochristen]

Thanks for your comprehensive analysis. Without going into it, the library has a known issue with deserialisation of multipolygon vector data. Simply said, it cannot handle 4 levels of vectors, which occurs when having multiple multipolygons or OpenLayers does internally uses this structure with complex vectors. Changing this would require a major refactoring. At first sight, it seems you run into this problem.