代码如下 
<asp:HyperLink ID="Hl_Class"  ForeColor="Blue" runat="server" Text="编辑" Target="_blank"
           NavigateUrl='<%#string.Format("Mg_PageEditSave.aspx?NounGID={0}&MgNounNID={1}",(Guid)ViewState["Gid"],(Guid)ViewState["Noun_NID"])%>'></asp:HyperLink>
哪里错误了