Replace 5th vowel

[angelica]

Hey,

I need to find the first letter in a message and replace it with the 5th vowel in another string. However it never gets into the condition in Red Color. Any help please ?

I also need to keep the count of the characters in the characterarray. ???

Private Sub Find5vowel()

        Dim vowelcounter, i As Integer
        Dim characterarray() As Char
        Dim vowelarray() As Char = {"a", " A", "e", "i", "I", "o", "O", "u", " U", "E"}
        Dim strmessage1 As String
        'RandomGen1 is a string of 200 letters which has been randomized
        characterarray = RandomGen1.ToCharArray()
        For i = 1 To characterarray.Length

            If vowelarray = characterarray(i) Then
                vowelcounter += 1           
              If vowelcounter = 5 Then 
                    letter5vowel = characterarray(i)
                    strmessage1 = characterarray.ToString
                    strmessage1 = strmessage1.Replace(letter5vowel, firstmessage)

                End If
            End If
        Next

                MessageBox.Show(strmessage1)

    End Sub

    Private Sub Findfirst()
        Try

            If txtmessage.Text = String.Empty Then
                MessageBox.Show("Message cannot be left empty!")
            Else
                strmessage = txtmessage.Text
                Dim messagearray() As Char

                messagearray = strmessage.ToCharArray()
                firstmessage = messagearray(0)
                ' MessageBox.Show(firstmessage)
            End If
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Findfirst()
        Find5vowel()

    End Sub