js display none

private void displayArea()
        {
         
            //string js = "this.document.getElementById('AddArea').style.display = '';this.document.getElementById('ContentPlaceHolder1_btnAdd').style.display = 'none';";
            string js = "this.document.getElementById('AddArea').style.display = '';this.document.getElementById('table2').style.display = 'none';this.document.getElementById('table3').style.display = 'none';";
            ScriptManager.RegisterStartupScript(this, this.Page.GetType(), "js1", js, true);
        }


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onclick="document.getElementById('AddArea').style.display = 'none'; document.getElementById('table2').style.display = '';document.getElementById('table3').style.display = '';"