Solution for one at a time loop
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Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim i As Integer ' i is used as a pointer and loop index
Dim l As Integer ' l is the number of characters in the input string
Dim strin As String ' strin holds the string the user types in
Dim c As String ' c is the character i is currently pointing at -- it increases each time through the loop
strin = txtIn.Text
l = strin.Length
txtOut.Clear()
i = 0
Do While i < l
c = strin.Substring(i, 1) ' get the current character from the input string
txtOut.AppendText(c & vbCrLf) ' display that character
i = i + 1 ' move the pointer to the next character
Loop
End Sub
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