This example illustrates how to implement a custom provider of image tiles. For this it's necessary to create a MapDataProviderBase class descendant and assign it to the ImageTilesLayer.DataProvider property.
The sample below shows how to load image tiles from a local cache. It might be possible only if you previously downloaded a bulk of image tiles from one of the available image tile providers. For example, a list of alternative OpenStreetMap image tile providers is available here: OpenStreetMap: Tile usage policy.
Note: If you don't need to create a custom data provider and only require changing the Uri to the location of image tiles, use the OpenStreetMapDataProvider.TileUriTemplate property.
Files to look at:• Form1.cs (VB: Form1.vb)