http://edndoc.esri.com/arcobjects/9.2/NET/1b14f488-84de-4e7f-8009-cfe612f8dcbe.htm
[C#]
// Intialize the Geoprocessor
Geoprocessor GP = new Geoprocessor();
// Intialize the MakeFeatureLayer tool
MakeFeatureLayer makefeaturelayer = new MakeFeatureLayer();
// Set up the GP tool parameters and run the tool
makefeaturelayer.in_features = @"C:\gp\nfld.gdb\wells";
makefeaturelayer.out_layer = "Wells_Lyr";
makefeaturelayer.where_clause = "WELL_YIELD > 150";
IGeoProcessorResult result = (IGeoProcessorResult)GP.Execute(makefeaturelayer,
null);
IFeatureClass fc;
IQueryFilter qf;
IGPUtilities gpUtils = new GPUtilitiesClass();
gpUtils.DecodeFeatureLayer(result.GetOutput(0), out fc, out qf);
IFeatureCursor cursor = fc.Insert(true);