Sorts an array using default and custom comparer - keys

The following example shows how to sort the values in an array using the default comparer and a custom comparer that reverses the sort order.

C# .NET


public class myReverserClass : IComparer
{
         // Calls CaseInsensitiveComparer.Compare with the parameters reversed.
         int IComparer.Compare( Object x, Object y )
         {
                  return( (new CaseInsensitiveComparer()).Compare( y, x ) );
         }
}

public static String DoTest()
{
         string strRet = "";

         // Creates and initializes a new Array and a new custom comparer.
         String[] myKeys = { "red", "GREEN", "YELLOW", "BLUE", "purple", "black", "orange" };
         String[] myValues = { "strawberries", "PEARS", "LIMES", "BERRIES", "grapes", "olives", "cantaloupe" };
         IComparer myComparer = new myReverserClass();

         // Displays the values of the Array.
         strRet += ( "The Array initially contains the following values:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts a section of the Array using the default comparer.
         Array.Sort( myKeys, myValues, 1, 3 );
         strRet += ( "After sorting a section of the Array using the default comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts a section of the Array using the reverse case-insensitive comparer.
         Array.Sort( myKeys, myValues, 1, 3, myComparer );
         strRet += ( "After sorting a section of the Array using the reverse case-insensitive comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts the entire Array using the default comparer.
         Array.Sort( myKeys, myValues );
         strRet += ( "After sorting the entire Array using the default comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts the entire Array using the reverse case-insensitive comparer.
         Array.Sort( myKeys, myValues, myComparer );
         strRet += ( "After sorting the entire Array using the reverse case-insensitive comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );         

         return strRet;
         
}

public static string PrintKeysAndValues( String[] myKeys, String[] myValues )
{
         string strRet = "\r\n";
         for ( int i = 0; i < myKeys.Length; i++ )
         {
                  strRet += String.Format(" {0,-10}: {1}", myKeys[i], myValues[i] );
                  strRet += "\r\n";
         }
         strRet += "\r\n";
         return strRet;
}

 

Blaze++ .NET

class myReverserClass : public IComparer
{
public:
         // Calls CaseInsensitiveComparer.Compare with the parameters reversed.
         int IComparer::Compare( Object& x, Object& y )
         {
                  CaseInsensitiveComparer cic;
                  return cic.Compare( y, x );
         }
};

static String DoTest()
{

         String strRet = "";

         // Creates and initializes a new Array and a new custom comparer.
         String keys[] = { "red", "GREEN", "YELLOW", "BLUE", "purple", "black", "orange" };
         Array myKeys(keys, 7);
         String values[] = { "strawberries", "PEARS", "LIMES", "BERRIES", "grapes", "olives", "cantaloupe" };
         Array myValues(values, 7);
         myReverserClass myComparer;

         // Displays the values of the Array.
         strRet += ( "The Array initially contains the following values:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts a section of the Array using the default comparer.
         Array::Sort( myKeys, myValues, 1, 3 );
         strRet += ( "After sorting a section of the Array using the default comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts a section of the Array using the reverse case-insensitive comparer.
         Array::Sort( myKeys, myValues, 1, 3, myComparer );
         strRet += ( "After sorting a section of the Array using the reverse case-insensitive comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts the entire Array using the default comparer.
         Array::Sort( myKeys, myValues );
         strRet += ( "After sorting the entire Array using the default comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );

         // Sorts the entire Array using the reverse case-insensitive comparer.
         Array::Sort( myKeys, myValues, myComparer );
         strRet += ( "After sorting the entire Array using the reverse case-insensitive comparer:" );
         strRet += PrintKeysAndValues( myKeys, myValues );         

         return strRet;
         
}

static String PrintKeysAndValues(Array& myKeys, Array& myValues )
{
         String strRet = "\r\n";
         for ( int i = 0; i < myKeys.Length; i++ )
         {
                  strRet += String::Format(" {0,-10}: {1}", myKeys[i], myValues[i] );
                  strRet += "\r\n";
         }
         strRet += "\r\n";
         return strRet;
}