OpenStreetMap in Blazor Maps Component

26 Jun 20248 minutes to read

The OpenStreetMap (OSM) is the online Maps provider built by a community of developers. It is free to use under an open license. It allows to view geographical data in a collaborative way from anywhere on the earth. The OSM map provides small tile images based on the requests and combines those images into a single image to display the map area in the Maps component.

Adding OpenStreetMap

The OSM Maps can be rendered by setting the UrlTemplate property with the OSM tile server URL. For more details about the OSM tile server, refer here.

@using Syncfusion.Blazor.Maps

<SfMaps>
    <MapsLayers>
        <MapsLayer UrlTemplate="https://tile.openstreetmap.org/level/tileX/tileY.png" TValue="string"></MapsLayer>
    </MapsLayers>
</SfMaps>

Enable zooming and panning

The OSM Maps layer can be zoomed and panned. Zooming helps to get a closer look at a particular area on a Maps for in-depth analysis. Panning helps to move Maps around to focus the targeted area.

@using Syncfusion.Blazor.Maps

<SfMaps>
    @* To zoom and pan *@
    <MapsZoomSettings Enable="true">
        <MapsZoomToolbarSettings>
            <MapsZoomToolbarButton ToolbarItems="new List<ToolbarItem>() { ToolbarItem.Zoom, ToolbarItem.ZoomIn, ToolbarItem.ZoomOut,
            ToolbarItem.Pan, ToolbarItem.Reset }"></MapsZoomToolbarButton>
        </MapsZoomToolbarSettings>
    </MapsZoomSettings>
    <MapsLayers>
        <MapsLayer UrlTemplate="https://tile.openstreetmap.org/level/tileX/tileY.png" TValue="string"></MapsLayer>
    </MapsLayers>
</SfMaps>

Adding markers and navigation line

Markers can be added to the layers of OSM Maps by setting the corresponding location’s coordinates of latitude and longitude using MapsMarker. Navigation lines can be added on top of an OSM Maps layer for highlighting a path among various places by setting the corresponding location’s coordinates of latitude and longitude in the MapsNavigationLine.

@using Syncfusion.Blazor.Maps

<SfMaps>
    <MapsZoomSettings ZoomFactor="4"></MapsZoomSettings>
    <MapsCenterPosition Latitude="29.394708" Longitude="-94.954653"></MapsCenterPosition>
    <MapsLayers>
        <MapsLayer UrlTemplate="https://tile.openstreetmap.org/level/tileX/tileY.png" TValue="string">
            @* Add marker *@
            <MapsMarkerSettings>
                <MapsMarker Visible="true" Height="25" Width="15" DataSource="Cities" TValue="City">
                </MapsMarker>
            </MapsMarkerSettings>
            @* Add navigation line *@
            <MapsNavigationLines>
                <MapsNavigationLine Visible="true" Color="blue" Angle="0.1" Latitude="new double[]{34.060620, 40.724546}"
                                    Longitude="new double[]{-118.330491,-73.850344}">
                </MapsNavigationLine>
            </MapsNavigationLines>
        </MapsLayer>
    </MapsLayers>
</SfMaps>

@code{
    public class City
    {
        public double Latitude { get; set; }
        public double Longitude { get; set; }
        public string Name { get; set; }
    }
    private List<City> Cities = new List<City> {
        new City { Latitude = 34.060620, Longitude = -118.330491,  Name="California" },
        new City{ Latitude = 40.724546, Longitude = -73.850344,  Name="New York"}
    };
}

Adding sublayer

Any GeoJSON shape can be rendered as a sublayer on top of the OSM Maps layer for highlighting a particular continent or country in the OSM map by adding another layer and specifying the Type of MapsLayer to SubLayer.

@using Syncfusion.Blazor.Maps

<SfMaps>
    <MapsLayers>
        <MapsLayer UrlTemplate="https://tile.openstreetmap.org/level/tileX/tileY.png" TValue="string">
        </MapsLayer>
        @* To add geometry shape as sublayer *@
        <MapsLayer ShapeData='new {dataOptions = "https://cdn.syncfusion.com/maps/map-data/africa.json"}'
                   Type="Syncfusion.Blazor.Maps.Type.SubLayer" TValue="string">
            <MapsShapeSettings Fill="blue"></MapsShapeSettings>
        </MapsLayer>
    </MapsLayers>
</SfMaps>

Enable legend

The legend can be added to the tile Maps by setting the Visible property of MapsLegendSettings to true.

@using Syncfusion.Blazor.Maps

<SfMaps Format="N0" EnableGroupingSeparator="true">
    <MapsZoomSettings Enable="true">
        <MapsZoomToolbarSettings>
            <MapsZoomToolbarTooltipSettings FontFamily="inherit"></MapsZoomToolbarTooltipSettings>
        </MapsZoomToolbarSettings>
    </MapsZoomSettings>
    <MapsLegendSettings Visible="true" Position="LegendPosition.Float" Height="123px" Width="200px" Type="LegendType.Markers" X="10" Y="247" Background="#E6E6E6" ShapePadding="10">
        <MapsLegendTextStyle FontFamily="inherit" Color="#000000" />
    </MapsLegendSettings>
    <MapsTitleSettings Text="Top 10 populated cities in the World">
        <MapsTitleTextStyle Size="16px" FontFamily="inherit" />
    </MapsTitleSettings>
    <MapsLayers>
        <MapsLayer UrlTemplate="https://a.tile.openstreetmap.org/level/tileX/tileY.png" TValue="string">
        <MapsMarkerSettings>
                <MapsMarker Visible="true" TValue="PopulationCityDetails" DataSource="@PopulatedCities" Shape="MarkerType.Circle" Fill="#FFFFFF" ColorValuePath="Color" LegendText="Name" Height="15" Width="15">
                    <MapsMarkerTooltipSettings Visible="true" ValuePath="Population" Format="City Name: ${Name}</br>Population: ${Population} million">
                        <MapsMarkerTooltipTextStyle FontFamily="inherit"></MapsMarkerTooltipTextStyle>
                    </MapsMarkerTooltipSettings>
                </MapsMarker>
            </MapsMarkerSettings>
        </MapsLayer>
    </MapsLayers>
</SfMaps>

@code{
    public class PopulationCityDetails
    {        
        public string Name { get; set; }
        public double Latitude { get; set; }
        public double Longitude { get; set; }
        public double Population { get; set; }
        public string Color { get; set; }
    };
    public List<PopulationCityDetails> PopulatedCities = new List<PopulationCityDetails> {
        new PopulationCityDetails { Name ="Tokyo", Latitude= 35.6805245924747, Longitude= 139.76770396213337, Population= 37435191, Color="#2EB6C8"},
        new PopulationCityDetails { Name ="Delhi", Latitude= 28.644800, Longitude= 77.216721, Population= 29399141, Color="#4A97F4"},
        new PopulationCityDetails { Name ="Shanghai", Latitude= 31.224361, Longitude= 121.469170, Population= 26317104, Color="#498082"},
        new PopulationCityDetails { Name ="Sao Paulo", Latitude= -23.550424484747914, Longitude= -46.646471636488315, Population= 21846507, Color="#FB9E67"},
        new PopulationCityDetails { Name ="Mexico City", Latitude= 19.427402397418774, Longitude= -99.131123716666, Population= 21671908, Color="#8F9DE3"},
        new PopulationCityDetails { Name ="Cairo ", Latitude= 30.033333, Longitude= 31.233334, Population= 20484965, Color="#7B9FB0"},
        new PopulationCityDetails { Name ="Dhaka", Latitude= 23.777176, Longitude= 90.399452, Population= 20283552, Color="#4DB647"},
        new PopulationCityDetails { Name ="Mumbai", Latitude= 19.08492049646163, Longitude= 72.87449446319248, Population= 20185064, Color="#30BEFF"},
        new PopulationCityDetails { Name ="Beijing", Latitude= 39.90395970055848, Longitude= 116.38831272088059, Population= 20035455, Color="#Ac72AD"},
        new PopulationCityDetails { Name ="Osaka", Latitude= 34.69024500601642, Longitude= 135.50746225677142, Population= 19222665, Color="#EFE23E"}
    };
}