Projection
Most mapping projections are handled automatically by SpatialReferences built into basemaps, feature layers,
and graphics. However, there is also a tool you can call directly to "Project" or "GetTransformation" between several
different SpatialReferences. In this sample, the maps are auto-calculating the projections, but the X/Y
coordinates and GeographicTransformation steps are calculated via the projection tool.
See the Source Code for the Display Projection page for more Wkid values.
Not all values will render properly with this GeoJSON map.
Starting Point
GeoBlazor
dymaptic
Get Transformation
About this sample
This GeoBlazor sample, written in Blazor for .NET developers, demonstrates the ProjectionEngine from the ArcGIS Maps SDK for JavaScript exposed through GeoBlazor's injected ProjectionEngine service together with SpatialReference and GeographicTransformation Razor components. The page shows two side-by-side 2D maps, each backed by a GeoJSONLayer of generalized world country polygons rendered as white shapes with purple outlines on a light blue background. Above the maps is a Starting Point form with longitude and latitude inputs (defaulting to a point in northeast Greenland). Each map has its own dropdown of Wkid options grouped by projection family — Equidistant (4326, 54028, 54027), Conformal (54026), Equal-area (54010, 54008), Gnomonic (102034), and Compromise (3857, 54016, 54042, 54050) — and a live readout of the projected X/Y coordinates of the starting point. A purple SimpleMarkerSymbol marks the starting point in each view. Below the maps is a 'Get Transformation' panel that calls ProjectionEngine.Project and ProjectionEngine.GetTransformation to display the starting Wkid, each GeographicTransformationStep, and the ending Wkid. The sample is intended to demonstrate spatial reference projection and transformation computation in a Blazor application without writing JavaScript.