关于LinkButton.enabled = false时，去掉javascript中弹出窗口的问题

我点击LinkButton弹出确定删除提示框
现在LinkButton.Enabled = false了
但是点击LinkButton时，还会弹出提示框，怎么让他不弹？

 

方法如下：
前台代码

<script language="javascript">

function btn_confirm(){

if(confirm("请确定是否删除此日志！")){return true;}

else{return false;}

}

</script>

 

<asp:LinkButton ID="btn_Delete" runat="server" CausesValidation="False" Text="删除" OnClick="btn_Delete_Click" CommandArgument='<%# Eval("PDR_id") %>'></asp:LinkButton>

 

后台代码

 protected void Repeater1_ItemDataBound(object sender, RepeaterItemEventArgs e)

    {

        Label lab = new Label();

        lab = (Label)e.Item.FindControl("lbl_userID");

        if (lab != null)

        {

            string PDR_user_id = lab.Text.ToString().Trim();

            if (Request.Cookies["user_id"] != null)

            {

                user_id = Request.Cookies["user_id"].Value.ToString();

            }

 

            if (PDR_user_id == user_id)

            {

                //实例化LinkButton

                LinkButton but = new LinkButton();

                but = (LinkButton)e.Item.FindControl("btn_Delete");

                but.Enabled = true;

                but.Attributes.Add("onclick", "return btn_confirm(this)");//LinkButton.Enabled = true时,javascript中才弹出确定删除窗口

 

                LinkButton but_UPdate = new LinkButton();

                but_UPdate = (LinkButton)e.Item.FindControl("btn_UPdate");

                but_UPdate.Enabled = true;

            }

            else

            {

                //实例化LinkButton

                LinkButton but = new LinkButton();

                but = (LinkButton)e.Item.FindControl("btn_Delete");

                but.Enabled = false;

 

                LinkButton but_UPdate = new LinkButton();

                but_UPdate = (LinkButton)e.Item.FindControl("btn_UPdate");

                but_UPdate.Enabled = false;

            }

        }

    }