Multiview Control and finding a TextBox in a view

How do you find a TextBox in a multiview control view? 
 
View myView = mviewMain.FindControl(myview.ID);
myview.FindControl(controlId).ID;
I also tried

regularExpressionValidator.ControlToValidate = mviewMain.Views[mviewMain.Views.Count].FindControl(controlId).ID;I created a view dynamically and then dynamically created a textbox. I want to assign a required field to the dynamically created text box?
Thanks for your help.



 

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