Array::Sort Method (Array^, Array^, Int32, Int32)
Sorts a range of elements in a pair of one-dimensional Array objects (one contains the keys and the other contains the corresponding items) based on the keys in the first Array using the IComparable implementation of each key.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- keys
-
Type:
System::Array^
The one-dimensional Array that contains the keys to sort.
- items
-
Type:
System::Array^
The one-dimensional Array that contains the items that correspond to each of the keys in the keysArray.
-or-
null to sort only the keysArray.
- index
-
Type:
System::Int32
The starting index of the range to sort.
- length
-
Type:
System::Int32
The number of elements in the range to sort.
| Exception | Condition |
|---|---|
| ArgumentNullException | keys is null. |
| RankException | |
| ArgumentOutOfRangeException | index is less than the lower bound of keys. -or- length is less than zero. |
| ArgumentException | |
| InvalidOperationException | One or more elements in the keysArray do not implement the IComparable interface. |
Each key in the keysArray has a corresponding item in the itemsArray. When a key is repositioned during the sorting, the corresponding item in the itemsArray is similarly repositioned. Therefore, the itemsArray is sorted according to the arrangement of the corresponding keys in the keysArray.
Each key within the specified range of elements in the keysArray must implement the IComparable interface to be capable of comparisons with every other key.
You can sort if there are more items than keys, but the items that have no corresponding keys will not be sorted. You cannot sort if there are more keys than items; doing this throws an ArgumentException.
If the sort is not successfully completed, the results are undefined.
This method uses the introspective sort (introsort) algorithm as follows:
If the partition size is fewer than 16 elements, it uses an insertion sort algorithm.
If the number of partitions exceeds 2 * LogN, where N is the range of the input array, it uses a Heapsort algorithm.
Otherwise, it uses a Quicksort algorithm.
This implementation performs an unstable sort; that is, if two elements are equal, their order might not be preserved. In contrast, a stable sort preserves the order of elements that are equal.
For arrays that are sorted by using the Heapsort and Quicksort algorithms, in the worst case, this method is an O(n log n) operation, where n is length.
The following code example shows how to sort two associated arrays where the first array contains the keys and the second array contains the values. Sorts are done using the default comparer and a custom comparer that reverses the sort order. Note that the result might vary depending on the current CultureInfo.
using namespace System; using namespace System::Collections; public ref class myReverserClass: public IComparer { private: // Calls CaseInsensitiveComparer::Compare with the parameters reversed. virtual int Compare( Object^ x, Object^ y ) = IComparer::Compare { return ((gcnew CaseInsensitiveComparer)->Compare( y, x )); } }; void PrintKeysAndValues( array<String^>^myKeys, array<String^>^myValues ) { for ( int i = 0; i < myKeys->Length; i++ ) { Console::WriteLine( " {0, -10}: {1}", myKeys[ i ], myValues[ i ] ); } Console::WriteLine(); } int main() { // Creates and initializes a new Array and a new custom comparer. array<String^>^myKeys = {"red","GREEN","YELLOW","BLUE","purple","black","orange"}; array<String^>^myValues = {"strawberries","PEARS","LIMES","BERRIES","grapes","olives","cantaloupe"}; IComparer^ myComparer = gcnew myReverserClass; // Displays the values of the Array. Console::WriteLine( "The Array initially contains the following values:" ); PrintKeysAndValues( myKeys, myValues ); // Sorts a section of the Array using the default comparer. Array::Sort( myKeys, myValues, 1, 3 ); Console::WriteLine( "After sorting a section of the Array using the default comparer:" ); // Sorts a section of the Array using the reverse case-insensitive comparer. Array::Sort( myKeys, myValues, 1, 3, myComparer ); Console::WriteLine( "After sorting a section of the Array using the reverse case-insensitive comparer:" ); PrintKeysAndValues( myKeys, myValues ); // Sorts the entire Array using the default comparer. Array::Sort( myKeys, myValues ); Console::WriteLine( "After sorting the entire Array using the default comparer:" ); PrintKeysAndValues( myKeys, myValues ); // Sorts the entire Array using the reverse case-insensitive comparer. Array::Sort( myKeys, myValues, myComparer ); Console::WriteLine( "After sorting the entire Array using the reverse case-insensitive comparer:" ); PrintKeysAndValues( myKeys, myValues ); } /* This code produces the following output. The Array initially contains the following values: red : strawberries GREEN : PEARS YELLOW : LIMES BLUE : BERRIES purple : grapes black : olives orange : cantaloupe After sorting a section of the Array using the default comparer: red : strawberries BLUE : BERRIES GREEN : PEARS YELLOW : LIMES purple : grapes black : olives orange : cantaloupe After sorting a section of the Array using the reverse case-insensitive comparer: red : strawberries YELLOW : LIMES GREEN : PEARS BLUE : BERRIES purple : grapes black : olives orange : cantaloupe After sorting the entire Array using the default comparer: black : olives BLUE : BERRIES GREEN : PEARS orange : cantaloupe purple : grapes red : strawberries YELLOW : LIMES After sorting the entire Array using the reverse case-insensitive comparer: YELLOW : LIMES red : strawberries purple : grapes orange : cantaloupe GREEN : PEARS BLUE : BERRIES black : olives */
Available since 10
.NET Framework
Available since 1.1