/OpenLayers.Blazor

An Map component for Blazor based on OpenLayers with support for swisstopo swiss maps.

Primary LanguageC#MIT LicenseMIT

OpenLayers.Blazor

This is a map component based on OpenLayers to show different types and layers of maps from sources like OpenStreet, Bing, SwissTopo ary WMTS/WMS compatible source with some features like markes or shape drawing. The component has implemented the swiss specific coordination projection (VL03/VL95) and therefore can project map content from swisstopo (https://map.geo.admin.ch/).

Release 2.0 changes and features

  • Full support for vector layers including adding shapes per layer
  • Capability to fully adjust vector styles
  • Shape selection feature with events on layers
  • Automatic update on a parameter change on layers and shapes (only when rendered as component)
  • Internal shape/drawing and marker layers are added on demand and are part of the layers collection
  • Fix when Map.InteractionsEnabled = false also no mouse events are handled
    • many more small improvements and bug fixes

Demo/Examples

https://openlayers-blazor-demo.laurent-christen.ch/

Usage

Setup

  • install nuget package dotnet add package OpenLayers.Blazor

  • Download the openlayers distribution js/css files https://github.com/openlayers/openlayers or from other sources and include them in the index.html file:

    <head>
    ...
        <link href="https://cdnjs.cloudflare.com/ajax/libs/openlayers/8.1.0/ol.min.css" rel="stylesheet" />
        <link href="_content/OpenLayers.Blazor/OpenLayers.Blazor.css" rel="stylesheet" />
        <script src="https://cdnjs.cloudflare.com/ajax/libs/openlayers/8.1.0/dist/ol.min.js"></script>
    ...
    </head>

Examples

    <SwissMap Style="height:800px">
        <Popup>
            <div id="popup" class="ol-box">
                @if (context is Marker marker)
                {
                    <h3>@marker.Text</h3>
                    <p>@marker.Coordinate.X / @marker.Coordinate.Y</p>
                }
            </div>
        </Popup>
        <Features>
            <Marker Type="MarkerType.MarkerPin" Coordinate="new Coordinate(2604200, 1197650)"></Marker>
            <Marker Type="MarkerType.MarkerFlag" Coordinate="new Coordinate(2624200, 1177650)" Text="Hallo" BackgroundColor="#449933" Popup></Marker>
            <Line Points="new []{new Coordinate(1197650, 2604200), new Coordinate(2624200, 1177650)}" BorderColor="cyan"></Line>
        </Features>
    </SwissMap>

    <OpenStreetMap Style="height:480px; width:640px" Zoom="5" Center="new Coordinate(0, 51)">
        <Layers>
            <Layer SourceType="SourceType.TileWMS"
                    Url="https://sedac.ciesin.columbia.edu/geoserver/ows?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&FORMAT=image%2Fpng&TRANSPARENT=true&LAYERS=gpw-v3%3Agpw-v3-population-density_2000&LANG=en"
                    Opacity=".3"
                    CrossOrigin="anonymous"></Layer>
        </Layers>
    </OpenStreetMap>