I have private ArcGIS Online account and i have some data. How is possibe use this for .NET applications?
Could you be a little more specific?
The ArcGIS Runtime SDK for .NET has APIs to work with most of the ArcGIS Portal.
I mean, use free ArcGIS online data.
I'd like to help but you have to be a lot more specific than that.
What kind of app are you trying to build? What kind of data from ArcGIS Online are you trying to do use? And what are you wanting to do with that data?
Did you read any of the getting started tutorials? What was unclear that you need help with? Did you look at the sample apps?
Developer's guide—ArcGIS Runtime SDK for .NET | ArcGIS for Developers
Access the ArcGIS platform—ArcGIS Runtime SDK for .NET | ArcGIS for Developers
GitHub - Esri/arcgis-runtime-samples-dotnet: Samples for the ArcGIS Runtime SDK for .NET - Desktop, Store, and Phone
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