Question

I have some pages in my website and a left menu control. Control helps to navigate from one page to another.

My query is -> While user try to navigate to another page, I want to impose some validation like in the current page if the form is not saved, user will be asked to save it by using a confirm messagebox and if user presses no button, then user will be allowed to navigate otherwise, system will first save the details and then navigate.

Edit – My page is a content page, I meant, this is using a master page.

Answer 1

Use the following steps

window.onbeforeunload = confirmExit;

and a function that stops/continue the page execution.

 function confirmExit() {            
            var email= document.getElementById("email");
            if (email.value != "")
                return "You have attempted to leave this page.  If you have made any changes to the fields without clicking the Save button, your changes will be lost.  Are you sure you want to exit this page?";
 }