The functionality of the BasicGeoprocessor object had been superseded by the new Geoprocessing framework of ArcGIS starting at version 9.0. Developers should utilize the new tools whenever possible.
IBasicGeoprocessor contains five methods: Dissolve, Merge, Clip, Intersect and Union. Access these methods using VBA or VB.
Dissolve creates a new layer or table by aggregating records in an input layer or table based on the values of a specified field.
Merge combines data from two or more layers of the same geometry type and creates a new feature class.
Clip extracts features of a point, line, or polygon layer based on the spatial extent of an overlay polygon layer. The attributes of the input feature class are carried over to the output feature class.
Intersect creates a new feature class by overlaying a line or polygon input layer with the polygons in an overlay layer. The output feature class has the combined attributes of both input layers, and only contains features that fall within the outline of the overlay polygons.
Union creates a new feature class by overlaying a polygon input layer with a polygon overlay layer. The output feature class has the combined attributes of both input layers, and contains features from the full spatial extent of both input layers.