Wizardcontrol with validation control

Hi All,
I have 4step in wizard.
Step1,Step2,Step3,Final
I want to validate controls in step 2 and Step3.
<StepNavigationTemplate>
<asp:Button Id="StepNextButton validationGroup="Step2" runat="server"/>
 
On Step3 I want validationGroup="Step3"
my code is very complex so please give me some hint or idea so i can put that idea to solve my problem.
If possible so please give a code sample.
 
Thanks in advance.
Swapnil
 
 
 
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