code

Public Class hackbar_union
    Public thongtin As String
    Public union, union_select As Integer
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        thongtin = TextBox1.Text
        union_select = Convert.ToDouble(thongtin)
        For union_select = 1 To union_select Step 1
            union = Convert.ToString(union_select)
            TextBox2.SetText = TextBox2.Text + union + ","
        Next
    End Sub
End Class