【单选题】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 va...
A.
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
B.
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
C.
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
D.
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 Sub