Creating GeoBlazor, the Asp.NET Core Web Mapping Library
This is a story about how I came to build the GeoBlazor SDK and component library. In 2022 dymaptic invited me to attend my first Esri Developer Summit, where I learned all about the ArcGIS platform, SDKs, and services. ArcGIS is the leading enterprise Geospatial Information software service, used by private and public sector agencies around the world. The scope of both the conference and the software was impressive, and I learned a great deal in that week.
While I was new to ArcGIS, I was already an experienced .NET software developer, with an especially keen interest in web development. I started off the conference by walking the exhibition hall, looking to learn all the different technologies available. I quickly found the ArcGIS Runtime SDK for .NET (now called "ArcGIS Maps SDK for .NET"), which allows using ArcGIS on desktop and mobile applications, previously via Xamarin but now updated to .NET MAUI. There were also SDKs for building add-ins to the ArcGIS Pro desktop application and the Unity game engine, both of which are built on .NET/C#.
One early decision I made for GeoBlazor was to offer more than simply a 1-1 wrapper around ArcGIS. I decided that GeoBlazor should be component-first, like Blazor and many JS frameworks. Thus, I came up with a pattern of Razor Components that could be stacked together in HTML-based markup to build a map view.
<MapView Longitude="-97.75188" Latitude="37.23308" Zoom="11" Style="height: 400px; width: 100%;">
<PortalItem Id="4a6cb60ebbe3483a805999d481c2daa5" />
<ScaleBarWidget Position="OverlayPosition.BottomLeft" />
We recently released version 2.0.0 of GeoBlazor where we continue to build upon the early component-model concept with additional layer types, widgets, and other components. GeoBlazor now also offers more support for user interactions, such as click event handlers, hit tests (determine what graphics were clicked on), and feature querying. You can see our full set of sample pages at https://samples.geoblazor.com.
GeoBlazor's core library is fully open-source, and all the code can be found on GitHub. If you'd like to help guide the next steps in the project's development, feel free to open an Issue, submit a Pull Request, or join our Discord server for further discussion.