StringDictionary.Item[String] Property is used to get or set the value associated with the specified key.
Syntax:
public virtual string this[string key] { get; set; }
Here, key is the Key of type System.String whose value is be to get or set.
Return Value: This property returns the value associated with the specified key. If the specified key is not found, Get returns null, and Set creates a new entry with the specified key.
Exception: This property throws ArgumentNullException
if the key is null.
Below programs illustrate the use of above-discussed property:
Example 1:
// C# code to get or set the value at // the specified key in StringDictionary using System;
using System.Collections;
using System.Collections.Specialized;
class GFG {
// Driver code
public static void Main()
{
// Creating a StringDictionary named my1
StringDictionary my1 = new StringDictionary();
// Adding key and value into the StringDictionary
my1.Add( "1" , "C" );
my1.Add( "2" , "C++" );
my1.Add( "3" , "Java" );
my1.Add( "4" , "Python" );
my1.Add( "5" , "C#" );
// Displaying the keys and
// values in StringDictionary
foreach (DictionaryEntry d in my1)
{
Console.WriteLine(d.Key + " " + d.Value);
}
Console.WriteLine( "\nAfter Item[String] Property: \n" );
// setting the value at key 2
my1[ "2" ] = "HTML" ;
// Displaying the keys and
// values in StringDictionary
foreach (DictionaryEntry d1 in my1)
{
Console.WriteLine(d1.Key + " " + d1.Value);
}
}
} |
Output:
3 Java 5 C# 4 Python 2 C++ 1 C After Item[String] Property: 3 Java 4 Python 2 HTML 1 C 5 C#
Example 2:
// C# code to get or set the value at // the specified key in StringDictionary using System;
using System.Collections;
using System.Collections.Specialized;
class GFG {
// Driver code
public static void Main()
{
// Creating a StringDictionary named my1
StringDictionary my1 = new StringDictionary();
// Adding key and value into the StringDictionary
my1.Add( "1" , "HTML" );
my1.Add( "2" , "CSS" );
my1.Add( "3" , "PHP" );
my1.Add( "4" , "MongoDB" );
my1.Add( "5" , "AngularJS" );
// Displaying the keys and
// values in StringDictionary
foreach (DictionaryEntry d in my1)
{
Console.WriteLine(d.Key + " " + d.Value);
}
Console.WriteLine( "\nAfter Item[String] Property: \n" );
// setting the value at Key 8
// here key 8 is not present
// so it will add a new key/value
// pair. see output
my1[ "8" ] = "C#" ;
// Displaying the keys and
// values in StringDictionary
foreach (DictionaryEntry d1 in my1)
{
Console.WriteLine(d1.Key + " " + d1.Value);
}
}
} |
Output:
3 PHP 5 AngularJS 4 MongoDB 2 CSS 1 HTML After Item[String] Property: 3 PHP 4 MongoDB 2 CSS 1 HTML 8 C# 5 AngularJS
Reference: