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vb.netdictionary.net-2.0initialization

Is it possible to initialise a New System.Collections.Generic.Dictionary with String key/value pairs?


Is it possible to create and initialise a System.Collections.Generic.Dictionary object with String key/value pairs in one statement?

I'm thinking along the lines of the constructor for an array of Strings..

e.g.

Private mStringArray As String() = {"String1", "String2", "etc"}

In case this is turns out to be a syntactic sugar kind of thing, I'd prefer an answer that I can use in .Net 2.0 (Visual Studio 2005), and Visual Basic - though I'm curious if it's possible at all so don't let that put you off ;o)


Solution

  • I don't think there is a way to do this out of the box in VB.NET 2, however you can extend the generic dictionary to make it work the way you want it to.

    The console app below illustrates this:

    Imports System.Collections.Generic
    
    Module Module1
    
        Sub Main()
    
            Dim items As New FancyDictionary(Of Integer, String)(New Object(,) {{1, "First Item"}, {2, "Second Item"}, {3, "Last Item"}})
            Dim enumerator As FancyDictionary(Of Integer, String).Enumerator = items.GetEnumerator
    
            While enumerator.MoveNext
                Console.WriteLine(String.Format("{0} : {1}", enumerator.Current.Key, enumerator.Current.Value))
            End While
    
            Console.Read()
    
        End Sub
    
        Public Class FancyDictionary(Of TKey, TValue)
            Inherits Dictionary(Of TKey, TValue)
    
            Public Sub New(ByVal InitialValues(,) As Object)
    
                For i As Integer = 0 To InitialValues.GetLength(0) - 1
    
                    Me.Add(InitialValues(i, 0), InitialValues(i, 1))
    
                Next
    
            End Sub
    
        End Class
    
    End Module