Showing RadtoolTip on Error input or submit button click

Hi all,
I am new one for telerik rad controls  and i want to validate RadTextBoxes (Empty,InvalidIputs) i have followed following link 
http://blogs.telerik.com/toddanglin/posts/08-12-12/showing-radtooltip-on-radinput-input-error.aspx
i want to show errors in this way but on submit button click if users left fields empty and i want to use asp validation controls for getting message text for error tool tip
Regard.
Khalid Sial