module - VB.NET Isogram checker

Question

I have this question here below. I am unable to figure it out. any help would be much appreciated with an explanation on how its done too.

In VB, write a function called Isogram that takes in one parameter - a string of lowercase letters and returns a Boolean depending on whether or not the parameter is an Isogram. An isogram is a word that has no repeating letters, consecutive or nonconsecutive.

Assume that the string parameter is all lower case letters with no punctuation or numbers or spaces.

I have not been given any code at all, however I have had a shot. I know it is completely wrong however.

Here is my code:

Module Module1

    Function isogram(ByVal StringToCheck As String)
        For i = 0 To StringToCheck.Length - 1
            If Not Char.IsLetter(StringToCheck.Chars(i)) Then
                Return False
            End If
        Next

        Return True
    End Function

    Sub Main()
        Dim temp As String
        Dim x As Boolean
        Console.Write("Please enter a string: ")
        temp = Console.ReadLine()

        x = isogram(temp)

        Select Case x
            Case True
                Console.WriteLine("True")
            Case False
                Console.WriteLine("False")
        End Select

        Console.ReadKey()
    End Sub

End Module

question from:https://stackoverflow.com/questions/65902451/vb-net-isogram-checker

Answer 1

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