Hashtable Constructor (IDictionary)

Imports System
Imports System.Collections
Imports System.Globalization

Public Class myCultureComparer
    Implements IEqualityComparer

    Dim myComparer As CaseInsensitiveComparer

    Public Sub New()
        myComparer = CaseInsensitiveComparer.DefaultInvariant
    End Sub 

    Public Sub New(ByVal myCulture As CultureInfo)
        myComparer = New CaseInsensitiveComparer(myCulture)
    End Sub 

    Public Function Equals1(ByVal x As Object, ByVal y As Object) _
        As Boolean Implements IEqualityComparer.Equals

        If (myComparer.Compare(x, y) = 0) Then 
            Return True 
        Else 
            Return False 
        End If 
    End Function 

    Public Function GetHashCode1(ByVal obj As Object) _
        As Integer Implements IEqualityComparer.GetHashCode
        Return obj.ToString().ToLower().GetHashCode()
    End Function 
End Class 

Public Class SamplesHashtable   

   Public Shared Sub Main()

      ' Create the dictionary. 
      Dim mySL As New SortedList()
      mySL.Add("FIRST", "Hello")
      mySL.Add("SECOND", "World")
      mySL.Add("THIRD", "!")

      ' Create a hash table using the default comparer. 
      Dim myHT1 As New Hashtable(mySL)

      ' Create a hash table using the specified IEqualityComparer that uses 
      ' the CaseInsensitiveComparer.DefaultInvariant to determine equality. 
      Dim myHT2 As New Hashtable(mySL, New myCultureComparer())

      ' Create a hash table using an IEqualityComparer that is based on 
      ' the Turkish culture (tr-TR) where "I" is not the uppercase 
      ' version of "i". 
      Dim myCul As New CultureInfo("tr-TR")
      Dim myHT3 As New Hashtable(mySL, New myCultureComparer(myCul))

      ' Search for a key in each hash table.
      Console.WriteLine("first is in myHT1: {0}", myHT1.ContainsKey("first"))
      Console.WriteLine("first is in myHT2: {0}", myHT2.ContainsKey("first"))
      Console.WriteLine("first is in myHT3: {0}", myHT3.ContainsKey("first"))

   End Sub 'Main 

End Class 'SamplesHashtable


'This code produces the following output. 
'Results vary depending on the system's culture settings. 
' 
'first is in myHT1: False 
'first is in myHT2: True 
'first is in myHT3: False