I have 2 html TR that i make them runat=\"server\" & visible=\"false\" and I have a dropdownlist called citiesDropDownList
runat=\"server\"
visible=\"false\"
citiesDropDownList
If you set visible = "false" on a server control, then the control is not even rendered to the browser. Set display: none instead and then show the control with display: block in your javascript.
visible = "false"
display: none
display: block