what is mean by StringDictionary and in what cases it ll be used?? simple example also needed ...

StringDictionary Class implements a hash table with the key and the value to be strings rather than objects.And here it must be noted that key cannot be a  null reference whereas the value can.Key is in case-insensitive manner means it is translated to lowercase before it is used with StringDictionary.

HI,

The StringDictionary implements a hash table with the key and the value strongly typed to be strings rather than objects.

StringDictionary myCol = new StringDictionary();

      myCol.Add( "red", "rojo" );
      myCol.Add( "green", "verde");

Console.WriteLine( "Displays the elements in the array:" );
      Console.WriteLine( "   KEY        VALUE" );
      for ( int i = 0; i < myArr.Length; i++ )
         Console.WriteLine( "   {0,-10} {1}", myArr[i].Key, myArr[i].Value );

      Console.WriteLine();

This class has more useful methods.