.NET C#: NameValueCollection

  1 using System;
  2 using System.Collections;
  3 using System.Collections.Specialized;
  4 
  5 public class ConsoleTest
  6 {
  7 
  8     public static void Main()
  9     {
 10 
 11         // Creates and initializes a new NameValueCollection.
 12         NameValueCollection myCol = new NameValueCollection();
 13         myCol.Add("red", "rojo");
 14         myCol.Add("green", "verde");
 15         myCol.Add("blue", "azul");
 16         myCol.Add("red", "rouge");
 17 
 18         // Displays the values in the NameValueCollection in two different ways.
 19         Console.WriteLine("Displays the elements using the AllKeys property and the Item (indexer) property:");
 20         PrintKeysAndValues(myCol);
 21         Console.WriteLine("Displays the elements using GetKey and Get:");
 22         PrintKeysAndValues2(myCol);
 23 
 24         // Gets a value either by index or by key.
 25         Console.WriteLine("Index 1 contains the value {0}.", myCol[1]);
 26         Console.WriteLine("Key \"red\" has the value {0}.", myCol["red"]);
 27         Console.WriteLine();
 28 
 29         // Copies the values to a string array and displays the string array.
 30         String[] myStrArr = new String[myCol.Count];
 31         myCol.CopyTo(myStrArr, 0);
 32         Console.WriteLine("The string array contains:");
 33         foreach (String s in myStrArr)
 34             Console.WriteLine("   {0}", s);
 35         Console.WriteLine();
 36 
 37         // Searches for a key and deletes it.
 38         myCol.Remove("green");
 39         Console.WriteLine("The collection contains the following elements after removing \"green\":");
 40         PrintKeysAndValues(myCol);
 41 
 42         // Clears the entire collection.
 43         myCol.Clear();
 44         Console.WriteLine("The collection contains the following elements after it is cleared:");
 45         PrintKeysAndValues(myCol);
 46 
 47     }
 48 
 49     public static void PrintKeysAndValues(NameValueCollection myCol)
 50     {
 51         Console.WriteLine("   KEY        VALUE");
 52         foreach (String s in myCol.AllKeys)
 53             Console.WriteLine("   {0,-10} {1}", s, myCol[s]);
 54         Console.WriteLine();
 55     }
 56 
 57     public static void PrintKeysAndValues2(NameValueCollection myCol)
 58     {
 59         Console.WriteLine("   [INDEX] KEY        VALUE");
 60         for (int i = 0; i < myCol.Count; i++)
 61             Console.WriteLine("   [{0}]     {1,-10} {2}", i, myCol.GetKey(i), myCol.Get(i));
 62         Console.WriteLine();
 63     }
 64 
 65 
 66 }
 67 
 68 /*
 69 
 70 This code produces the following output.
 71 
 72 Displays the elements using the AllKeys property and the Item (indexer) property:
 73    KEY        VALUE
 74    red        rojo,rouge
 75    green      verde
 76    blue       azul
 77 
 78 Displays the elements using GetKey and Get:
 79    [INDEX] KEY        VALUE
 80    [0]     red        rojo,rouge
 81    [1]     green      verde
 82    [2]     blue       azul
 83 
 84 Index 1 contains the value verde.
 85 Key "red" has the value rojo,rouge.
 86 
 87 The string array contains:
 88    rojo,rouge
 89    verde
 90    azul
 91 
 92 The collection contains the following elements after removing "green":
 93    KEY        VALUE
 94    red        rojo,rouge
 95    blue       azul
 96 
 97 The collection contains the following elements after it is cleared:
 98    KEY        VALUE
 99 
100 
101 */