Find Last Character of Given String using VB.NET

======================This is the Code
Dim str As String = "abcd"
        Dim ss As String = str(str.Length - 1)
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output :d
=============if we want 'c' of given string then we use-
Dim str As String = "abcd"
        Dim ss As String = str(str.Length - 2)
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output :c
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