UrlEncode

ASP.NET 快速入门教程/使用服务器控件/执行页导航（方案 2）里有两段代码不是很清楚。
UrlEncode前面的相关内容为何有点不同呢？

源页面向目标页面发送参数的代码。
<script language="C#" runat="server">

        void EnterBtn_Click(Object Src, EventArgs E) {

            // Navigate to a new page (passing name as a querystring argument) if
            // user has entered a valid name value in the <asp:textbox>

            if (Name.Text != "") {
               Response.Redirect("Controls_NavigationTarget_cs.aspx?name=" + System.Web.HttpUtility.UrlEncode(Name.Text));
            }
            else {
               Message.Text = "Hey! Please enter your name in the textbox!";
            }
        }

    </script>
目标页面接收参数的代码：
 <script language="C#" runat="server">

        void Page_Load(Object Sender, EventArgs e) {

           if (!Page.IsPostBack) {
              NameLabel.Text = Server.HtmlEncode(Request.QueryString["Name"]);
           }
        }

    </script>