Métodos de búsqueda y ordenamiento en listas y arrays en .NET (Parte 2)

Abundando en el método Sort de listas genéricas, a continuación muestro dos formas de ordenar listas genéricas de objetos en VB.Net.

Para ambas formas utilizaré a modo de ejemplo la siguiente clase:

Public Class myKeyAndData
   Private pnKey As Integer
   Private pcData As String

   Public Sub New()
      pnKey = 0
      pcData = ""
   End Sub

   Public Sub New(ByVal tnKey As Integer, ByVal tcData As String)
      pnKey = tnKey
      pcData = tcData
   End Sub

   Public Property Key() As Integer
   Get
      Return pnKey
   End
   Get
   Set(ByVal value As Integer)
      pnKey = value
   End Set
   End Property
   Public Property Data() As String
   Get
      Return pcData
   End Get
   Set(ByVal value As String)
      pcData = value
   End Set
   End Property
End Class

METODO 1: Definir una clase adicional que implemente la interface IComparer.

Private Class ItemsComparer
Implements IComparer(Of myKeyAndData)
   Public Function Compare(ByVal p1 As myKeyAndData, _
         ByVal p2 As myKeyAndData) As Integer Implements _
         IComparer(Of myKeyAndData).Compare
      Return p1.Data.CompareTo(p2.Data)
   End Function
End Class

Ejemplo:

   Dim loLista as new List(of myKeyAndData)
   loLista.add(new miKeyAndData(1,"Rodolfo")
   loLista.add(new miKeyAndData(2,"Antonio")
   loLista.add(new miKeyAndData(3,"Mario")
   loLista.add(new miKeyAndData(4,"Carlos")
   loLista.Sort(New ItemsComparer)

METODO 2: Hacer que la clase implemente la interface IComparable.

Public Class myKeyAndData
Implements IComparable(Of myKeyAndData)
   Private pnKey As Integer
   Private pcData As String

   Public Sub New()
      pnKey = 0
      pcData = ""
   End Sub

   Public Sub New(ByVal tnKey As Integer, ByVal tcData As String)
      pnKey = tnKey
      pcData = tcData
   End Sub

   Public Property Key() As Integer
   Get
      Return pnKey
   End Get
   Set(ByVal value As Integer)
      pnKey = value
   End Set
   End Property

   Public Property Data() As String
   Get
      Return pcData
   End Get
   Set(ByVal value As String)
      pcData = value
   End Set
   End Property

   Public Function CompareTo(ByVal toOtro As myKeyAndData) As Integer _
            Implements IComparable(Of myKeyAndData).CompareTo
      return Data.CompareTo(toOtro.Data)
   End Function

End Class

Ejemplo:

   Dim loLista as new List(of myKeyAndData)
   loLista.add(new miKeyAndData(1,"Rodolfo")
   loLista.add(new miKeyAndData(2,"Antonio")
   loLista.add(new miKeyAndData(3,"Mario")
   loLista.add(new miKeyAndData(4,"Carlos")
   loLista.Sort()

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