[C#]
     //ISelectionSet Example
    //example uses a USA "states" feature class in a Personal Geodatabase
    public void ISelectionSet_Example(IFeatureClass featureClass)
    {
        //This function creates various SelectionSets on the table and modifies them using the ISelectionSet methods.
        IDataset dataset = (IDataset)featureClass;
        //Set up query filter and use it to create the selection set.
        IQueryFilter queryFilter = new QueryFilterClass();
        queryFilter.WhereClause = "SUB_REGION = 'Pacific'";
        //use the query filter to select features
        ISelectionSet selectionSet = featureClass.Select(queryFilter, esriSelectionType.esriSelectionTypeHybrid, esriSelectionOption.esriSelectionOptionNormal, dataset.Workspace);
       
        //use an IEnumIDs to read the SelectionSet IDs
        IEnumIDs enumIDs = selectionSet.IDs;
        int fieldIndex = featureClass.FindField("STATE_NAME");
        string s = "{0}ID - STATE_NAME";
        IFeature feature;
        int iD = enumIDs.Next();
        while (iD != -1) //-1 is reutned after the last valid ID has been reached
        {
            feature = featureClass.GetFeature(iD);
            s += "{0}" + iD + ": " + feature.get_Value(fieldIndex);
            iD = enumIDs.Next();
        }
        //report some information about the selection
        Console.WriteLine("A SelectionSet containing: {1} Rows {0}has been created using the query: {2} {0}this selection set was created on the feature class: {3}{0}" + s + "{0}",Environment.NewLine, selectionSet.Count,queryFilter.WhereClause,dataset.Name);
        //add a list of features (OID's) to the selection set
        System.Collections.Generic.List<int> constructOIDAddList = new System.Collections.Generic.List<int>();
        constructOIDAddList.Add(22); // Nevada
        constructOIDAddList.Add(23); // Utah
        constructOIDAddList.Add(36); // Arizona
        int[] oidAddList = constructOIDAddList.ToArray();
        //pass the oidList by reference
        selectionSet.AddList(oidAddList.Length, ref oidAddList[0]);
        Console.WriteLine("{1} Features added to SelectionSet {0}{2} feature total in SelectionSet{0}", Environment.NewLine, oidAddList.Length.ToString(), selectionSet.Count);
        //remove a list of feature (OID's) from the selection set
        System.Collections.Generic.List<int> constructOIDDeleteList = new System.Collections.Generic.List<int>();
        constructOIDDeleteList.Add(49);  // Hawaii
        constructOIDDeleteList.Add(50); // Alaska
        int[] oidDeleteList = constructOIDDeleteList.ToArray();
        selectionSet.RemoveList(oidDeleteList.Length, ref oidDeleteList[0]);
        Console.WriteLine("{1} Features removed from SelectionSet {0}{2} feature total in SelectionSet{0}", Environment.NewLine, oidDeleteList.Length.ToString(), selectionSet.Count);
        //create second selection set by combining the first two
        queryFilter.WhereClause = "SUB_REGION = 'W N Cen'";
        ISelectionSet selectionSet2 = featureClass.Select(queryFilter, esriSelectionType.esriSelectionTypeHybrid, esriSelectionOption.esriSelectionOptionNormal, dataset.Workspace);
        //create a new selection set by combing the first two
        ISelectionSet resultSet;
        selectionSet.Combine(selectionSet2, esriSetOperation.esriSetUnion, out resultSet);
        Console.WriteLine("A second SelectionSet containing: {1} Features {0}has been created using the query: {2} {0}this selection set has been combined with the existing SelectionSet {0}the resulting selection set resultSet contains: {3} Features{0}", Environment.NewLine, selectionSet2.Count, queryFilter.WhereClause, resultSet.Count);
        //create a third selection set by selecting from the SelectionSet containing the West North Centeral States
        queryFilter.WhereClause = "STATE_NAME in ('Iowa', 'Minnesota', 'Missouri')"; //All of the states East of the Mississippi River
        ISelectionSet selectionSet3 = selectionSet2.Select(queryFilter,esriSelectionType.esriSelectionTypeHybrid,esriSelectionOption.esriSelectionOptionNormal,dataset.Workspace);
        //create a new selection set by combining it with the one corresponding with the result of the first selection combine
        //The operator esriSetSymDifference is a XOR so the content of the selectSet3 will be removed from the first set
        resultSet.Combine(selectionSet3, esriSetOperation.esriSetSymDifference,out resultSet);
        Console.WriteLine("A third SelectionSet containing: {1} Features {0}has been created using the query: {2} {0}this selection set has been removed from the existing SelectionSet {0}the resulting selection set resultSet contains: {3} Features{0}", Environment.NewLine, selectionSet3.Count, queryFilter.WhereClause, resultSet.Count);
        //create a FeatureCursor on the selection set to retrieve the selected records
        queryFilter.WhereClause = "STATE_NAME like '*a'";
        ICursor cursor;
        resultSet.Search(queryFilter,false,out cursor);
        IFeatureCursor featureCursor = (IFeatureCursor)cursor;
        s = null as string;
        int recordCount = 0;
        feature = featureCursor.NextFeature();
        while (feature != null)
        {
            recordCount++;
            s += "{0}" + feature.get_Value(fieldIndex);
            feature = featureCursor.NextFeature();
        }
        Console.WriteLine("Using iSelectionSet::Search with the query: {1} {0}we find that the resultSet from the XOR combine {0}contains the following states with names ending in a: " + s, Environment.NewLine, queryFilter.WhereClause, featureClass.AliasName);
        //Release the Cursors
        System.Runtime.InteropServices.Marshal.ReleaseComObject(cursor);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(featureCursor);
    }

[Visual Basic .NET, C++]
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