Esta propiedad se usa para obtener o establecer el valor asociado con la clave especificada en el Diccionario.
Sintaxis:
public TValue this[TKey key] { get; set; }
Aquí, key es la clave del valor que se va a obtener o establecer.
Valor de la Propiedad: Es el valor asociado a la clave especificada. Si no se encuentra la clave especificada, una operación de obtención arroja una excepción KeyNotFoundException y una operación de establecimiento crea un nuevo elemento con la clave especificada.
Excepciones:
- ArgumentNullException : si la clave es nula.
- KeyNotFoundException : si se recupera la propiedad y la clave no existe en la colección.
Ejemplo:
// C# code to get or set the value
// associated with the specified key
using System;
using System.Collections;
using System.Collections.Generic;
class GFG {
// Driver code
public static void Main()
{
// Creating a Dictionary named myDict
Dictionary<string, string> myDict = new Dictionary<string, string>();
// Adding key/value pairs in myDict
myDict.Add("Australia", "Canberra");
myDict.Add("Belgium", "Brussels");
myDict.Add("Netherlands", "Amsterdam");
myDict.Add("China", "Beijing");
myDict.Add("Russia", "Moscow");
myDict.Add("India", "New Delhi");
// Displaying the key/value pairs in myDict
foreach(KeyValuePair<string, string> k in myDict)
{
Console.WriteLine("Key = {0}, Value = {1}",
k.Key, k.Value);
}
// Displaying the value associated
// with key "Russia"
Console.Write("\nValue associated with Russia: ");
Console.Write(myDict["Russia"]);
// Setting the value associated with key "Russia"
myDict["Russia"] = "Saint Petersburg";
// Displaying the value associated
// with key "Russia"
Console.Write("\n\nValue associated with Russia After Setting: ");
Console.Write(myDict["Russia"]);
// Displaying the value associated
// with key "India"
Console.Write("\n\nValue associated with India: ");
Console.Write(myDict["India"]);
// Setting the value associated with key "India"
myDict["India"] = "Mumbai";
// Displaying the value associated
// with key "India"
Console.Write("\n\nValue associated with India After Setting: ");
Console.Write(myDict["India"]);
Console.WriteLine("\n");
// Displaying the key/value pairs in myDict
foreach(KeyValuePair<string, string> k1 in myDict)
{
Console.WriteLine("Key = {0}, Value = {1}",
k1.Key, k1.Value);
}
}
}
Producción:
Key = Australia, Value = Canberra Key = Belgium, Value = Brussels Key = Netherlands, Value = Amsterdam Key = China, Value = Beijing Key = Russia, Value = Moscow Key = India, Value = New Delhi Value associated with Russia: Moscow Value associated with Russia After Setting: Saint Petersburg Value associated with India: New Delhi Value associated with India After Setting: Mumbai Key = Australia, Value = Canberra Key = Belgium, Value = Brussels Key = Netherlands, Value = Amsterdam Key = China, Value = Beijing Key = Russia, Value = Saint Petersburg Key = India, Value = Mumbai
Referencia:
Publicación traducida automáticamente
Artículo escrito por Kirti_Mangal y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA