Public Class Form1

    Private Sub txtsides_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtsides.TextChanged
        If txtsides.Text = 3 Then
            lblshape.Text = ("Triangle")
        ElseIf txtsides.Text = 4 Then
            lblshape.Text = ("Quadrilateral")
        ElseIf txtsides.Text = 5 Then
            lblshape.Text = ("Pentagon")
        ElseIf txtsides.Text = 6 Then
            lblshape.Text = ("Hexagon")
        ElseIf txtsides.Text = 7 Then
            lblshape.Text = ("Heptagon")
        ElseIf txtsides.Text = 8 Then
            lblshape.Text = ("Octogon")
        ElseIf txtsides.Text = 9 Then
            lblshape.Text = ("Nonagon")
        ElseIf txtsides.Text = 10 Then
            lblshape.Text = ("Decagon")
        End If

        If txtsides.Text > 10 Then
            lblshape.Text = ("Error")
        End If

        If txtsides.Text < 3 Then
            lblshape.Text = ("Error")
        End If


    End Sub
End Class