HTML text box controls

I need a help. i have a form. which so many Html text box controls. i made it as runat='server'. i am in need to make it visible or hidden dynamically. for that i have to get the control of these text boxes. how can we do that. if it was ASP text boxes we can use like

Dim Txt1 As TextBox = CType(TblLQC.FindControl("Txt1"), TextBox). i dont know what we can do for HTML text box controls. can anyone please help me in this?
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