asp.net web form in multiple browser tabs

Question

I have a grid view and an edit button in the grid view. On edit button click I am opening a new aspx page that has text fields for input the data. When a user copies the URL of the gridview and opens it in a new tab of any browser then click on the edit button for two different records. If the user changes anything in the first tab and submits it. It changes the info for the record on the second tab. It is happening because I am passing userid in session to the form aspx page and session got updated when user opens the second record in the new tab.

Are there only two ways to passing data to aspx page?

1. using session
2. using a query string

I don't want to use the query string. Please help thank you.

Answer 1

You are writing a ASP.Net application, so at the end of the day there is only that much you can do. You can request some things off the browser, but if he actually does it is entirely up to it.

You can make it unlikely to happen by accident, using the HTML Links target property . This requests the browser to re-use any alread open tabs for this record. But that will not prevent a dedicated person from still opening 2 copies.

A pretty simple way to avoid race conditions in general, is the SQL rowversion column. You retreive the rowversion with the rest. You keep it along in a hidden formular field (that is what they are there for). When writing the update, check if it still matches before the write. If yes, you update. If not, somebody has modified the record since then and you reject the update. Can be the same user in another tab, can be another user at the end of the world. Could be that this tab was opened a year ago, surviving on sleep mode. It does not mater - any change trips this protection.