Is it possible to set the text of a label in a gridview edit mode?

[ImmavetaR]

I have a gridview in which edit mode is possible and when the user finishes to enter the edited data I preform some checking to see if the data fits some requirements I have.my question: is it possible to put in edit item template both textbox for entering data and a label that will function as an error label?is it possible to set the text of the label from within the editing function? or can I only get its data (read only)?example:\[code\]<EditItemTemplate> <asp:TextBox ID="txtEmail" Width="98%" runat="server" CssClass="cssWidth"></asp:TextBox><asp:Label ID="emailerror" runat="server" CssClass="cssWidth"/></EditItemTemplate>\[/code\]my goal is to perform the wanted tests and if my email address is not correct to set the label's text with an error message.if it's not possible I would appriciate any thought on how to display this error message in the best waythanks