How to: Show Tooltips for Map Shapes
This example illustrates how to display tooltips for shapes loaded from Shapefiles (Countries.dbf, Countries.shp).
Note that a tooltip displays information (a country name, population) for each map shape from Shapefiles.
To see information (a country name, population) obtained from a Shapefile on a toolltip, specify NAME and POP_EST attributes in the VectorLayerBase.ToolTipPattern property.
Then, enable map tooltips by setting the MapControl.ToolTipEnabled property to true.