When validation is not working or not being fire , then where we use (Page.IsValid)? Use it at the Button for which you are using.
Use this when validation is not working on the page -
On the Button_Submit.
When we have used validation on the page and validation is not working on Button click. Then use use Page.Isvalid on the Buttion Click.. Like that..
Protected void btnSubmit_Click(Object sender, EventArgs e)
The Vagrant (The Vagrant #1), by Peter Newman
14 hours ago