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ASP.Net Page Validation and Window Unload

Posted By:      Posted Date: September 15, 2010    Points: 0   Category :ASP.Net
I am getting some weird issue on my asp.net page.Here is the scenario:I have a asp.net page with a textbox (ctrl#1) and a dropdown control (ctrl#2). Each control have their CausesValidation and AutoPostBack set to true. I have another dropdown control (ctrl#3) on the same page which allows the user to navigate to some other page. I have added an alert message for the user (on window.onbeforeunload event) to warn the user of any unsaved changes on the page. User can choose to stay on the current page by clicking Cancel.So far so good... All works fine when the data is changed on the page  and user tries to navigate away from the current page using the above dropdown control (ctrl#3). The window.onbeforeunload fires and user gets the alert message. Happy user.Now comes the issue....When there is any invalid data on the page and the asp.net validation has fired, now, when the user tries to navigate away from the current page, he does not get any alert. It seems as if the window.onbeforeunload does not fire in this case when there is invalid data on page. I am not sure why this is happening!Can someone please share some thoughts and/or suggest a solution please?

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