Imports System
Imports System.Collections.Generic

Module Program
    Sub Main()
        ' To create an empty map, use the New keyword
        Dim m As New Dictionary(Of String, Integer)()

        ' Set key/value pairs using typical name(key) = val syntax.
        m("k1") = 7
        m("k2") = 13

        ' Printing a map with Console.WriteLine will show all of
        ' its key/value pairs.
        Console.WriteLine("map: {0}", String.Join(", ", m))

        ' Get a value for a key with name(key).
        Dim v1 As Integer = m("k1")
        Console.WriteLine("v1: {0}", v1)

        ' If the key doesn't exist, an exception is thrown.
        ' You can use TryGetValue to safely get a value.
        Dim v3 As Integer
        If m.TryGetValue("k3", v3) Then
            Console.WriteLine("v3: {0}", v3)
        Else
            Console.WriteLine("v3: Key not found")
        End If

        ' The Count property returns the number of key/value
        ' pairs in a Dictionary.
        Console.WriteLine("len: {0}", m.Count)

        ' The Remove method removes key/value pairs from
        ' a Dictionary.
        m.Remove("k2")
        Console.WriteLine("map: {0}", String.Join(", ", m))

        ' To remove all key/value pairs from a Dictionary, use
        ' the Clear method.
        m.Clear()
        Console.WriteLine("map: {0}", String.Join(", ", m))

        ' The ContainsKey method can be used to check if a key
        ' exists in the Dictionary.
        Dim prs As Boolean = m.ContainsKey("k2")
        Console.WriteLine("prs: {0}", prs)

        ' You can also declare and initialize a new Dictionary in
        ' the same line with this syntax.
        Dim n As New Dictionary(Of String, Integer) From {
            {"foo", 1},
            {"bar", 2}
        }
        Console.WriteLine("map: {0}", String.Join(", ", n))

        ' Visual Basic .NET doesn't have a built-in function to compare
        ' Dictionaries. You can create a custom function or use LINQ.
        Dim n2 As New Dictionary(Of String, Integer) From {
            {"foo", 1},
            {"bar", 2}
        }
        If n.Count = n2.Count AndAlso Not n.Except(n2).Any() Then
            Console.WriteLine("n == n2")
        End If
    End Sub
End Module