SortedList
The SortedList class represents a collection of key-and-value pairs that are sorted by the keys and are accessible by key and by index.
A sorted list is a combination of an array and a hash table. It contains a list of items that can be accessed using a key or an index. If you access items using an index, it is an ArrayList, and if you access items using a key, it is a Hashtable. The collection of items is always sorted by the key value.
Several Commonly Used Methods Defi ned by SortedList :
| Method | Description |
|---|---|
| public virtual bool ContainsKey(object key) | Returns true if key is a key in the invoking SortedList. Returns false otherwise. |
| public virtual bool ContainsValue(object value) |
Returns true if value is a value in the invoking SortedList. Returns false otherwise. |
| public virtual object GetByIndex(int index) | Returns the value at the index specified by index. |
| public virtual IDictionaryEnumerator GetEnumerator( ) |
Returns an IDictionaryEnumerator for the invoking SortedList. |
| public virtual object GetKey(int index) | Returns the value of the key at the index specified by index. |
| public virtual IList GetKeyList( ) | Returns an IList collection of the keys in the invoking SortedList. |
| public virtual IList GetValueList( ) | Returns an IList collection of the values in the invoking SortedList. |
| public virtual int IndexOfKey(object key) | Returns the index of the key specified by key. Returns –1 if the key is not in the list. |
| public virtual int IndexOfValue(object value) | Returns the index of the first occurrence of the value specified by value. Returns –1 if the value is not in the list. |
| public virtual void SetByIndex(int index, object value) |
Sets the value at the index specified by index to the value passed in value. |
| public static SortedList Synchronized(SortedList list) |
Returns a synchronized version of the SortedList passed in list. |
| public virtual void TrimToSize( ) | Sets Capacity to Count. |
Example
using System;
using System.IO;
using System.Collections;
namespace ConsoleApplication1
{
class Program
{
static void Main()
{
// Create a sorted SortedList.
SortedList sl = new SortedList();
// Add elements to the table
sl.Add("house", "Dwelling");
sl.Add("car", "Means of transport");
sl.Add("book", "Collection of printed words");
sl.Add("apple", "Edible fruit");
// Can also add by using the indexer.
sl["tractor"] = "Farm implement";
// Get a collection of the keys.
ICollection c = sl.Keys;
// Use the keys to obtain the values.
Console.WriteLine("Contents of list via indexer.");
foreach (string str in c)
Console.WriteLine(str + ": " + sl[str]);
Console.WriteLine();
// Display list using integer indexes.
Console.WriteLine("Contents by integer indexes.");
for (int i = 0; i < sl.Count; i++)
Console.WriteLine(sl.GetByIndex(i));
Console.WriteLine();
// Show integer indexes of entries.
Console.WriteLine("Integer indexes of entries.");
foreach (string str in c)
Console.WriteLine(str + ": " + sl.IndexOfKey(str));
Console.Read();
}
}
}
