how to validate server side validation and client side validation in one text box

Validation is process,  in this process we filter data.
client side happen  after fill the  data inside control or  before  submit a data from application ,it's depends of user need and business requirement .we use different type of tools and technology  for validate control.
Server side validation happen  when we retrieve data from server that time we checked data is proper format or not it means sever data compare with some Validation case .
.http://www.aspsnippets.com/Articles/TextBox-Validation-using-JavaScript.aspx