[单选] 下列（）不是实现层动画的条件。

You create a Web Form. The Web Form uses the FormView control to enable a user to edit a record in the database. When the user clicks the Update button on the FormView control, the application must validate that the user has entered data in all of the fields. You need to ensure that the Web Form does not update if the user has not entered data in all of the fields. Which code segment should you use? （） Protected Sub FormView1_ItemUpdating(ByVal sender As Object, _ ByVal e As System.Web.UI.WebControls.FormViewUpdateEventArgs) _ Handles FormView1.ItemUpdating Dim entry As DictionaryEntry For Each entry In e.Keys If entry.Value.ToString() = System.String.Empty Then e.Cancel = True Return End If Next entryEnd Sub。 Protected Sub FormView1_ItemUpdated(ByVal sender As Object, _ ByVal e As System.Web.UI.WebControls.FormViewUpdatedEventArgs) _ Handles FormView1.ItemUpdated Dim entry As DictionaryEntry For Each entry In e.NewValues If entry.Value.Equals("") Then e.KeepInEditMode = True Return End If Next entryEnd Sub。 Protected Sub FormView1_ItemUpdating(ByVal sender As Object, _ ByVal e As System.Web.UI.WebControls.FormViewUpdateEventArgs) _ Handles FormView1.ItemUpdating Dim entry As DictionaryEntry For Each entry In e.NewValues If entry.Value.Equals("") Then e.Cancel = True Return End If Next entryEnd Sub。 Protected Sub FormView1_ItemUpdated(ByVal sender As Object, _ ByVal e As System.Web.UI.WebControls.FormViewUpdatedEventArgs) _ Handles FormView1.ItemUpdated Dim entry As DictionaryEntry For Each entry In e.Keys If entry.Value.ToString() = System.String.Empty Then e.KeepInEditMode = True Return End If Next entryEnd Su。 GB175-2008中，水泥密度的单位是kg/m3。 Which of the following commands will cause RIPng to originate a default route advertisement whilesuppressing all other routes？（） Rl（config-if）#ipv6 default-information originate。 Rl（config-router）#ipv6 rip 〈process-name〉 default-information only。 Rl（config）#ipv6 route ：：/0 null 0。 Rl（config-if）#ipv6 rip 〈process-name〉 default-information only。 Rl（config-router）#ipv6 rip route ；：/0 originate。 Rl（config-router）#aggregate-address ：：/0 summarize-route。 请简述IP地址的分类方法，并说明什么是IP子网，划分IP子网有什么作用？ 胎粪的排出在出生后12小时，为墨绿色，喂奶后很块转为含奶块的金黄色，若24小时不见胎粪排出，要警惕（）畸形。 酶系统。 泌尿系统。 呼吸道。 消化道。 下列（）不是实现层动画的条件。