Detecting browser 'Refresh' from Code behind in C#
Browser 'Refresh' is always a cause of concern for the developers. It becomes even more worse when the page interacts with the database. As each refresh, if not handled, would lead to the database action repeated.
This could lead to inconsistency in database or even break the application.
One way could be to detect 'refresh' using javascript and disable F5 or right click..but there are so many other ways end-user can initiate 'Refresh' action for e.g. by using CTRL+R on the keyboard...
The best way to stop 'Refresh' calling your program again is to detect it at the server side and handle it..
The following code snippet detects 'Refresh' in page_load function
bool IsPageRefresh = false;
//this section of code checks if the page postback is due to genuine submit by user or by pressing "refresh"
if (!IsPostBack)
{
ViewState["ViewStateId"] = System.Guid.NewGuid().ToString();
Session["SessionId"] = ViewState["ViewStateId"].ToString();
}
else
{
if (ViewState["ViewStateId"].ToString() != Session["SessionId"].ToString())
{
IsPageRefresh = true;
}
Session["SessionId"] = System.Guid.NewGuid().ToString();
ViewState["ViewStateId"] = Session["SessionId"].ToString();
}
You can then use the 'IsPageRefresh' boolean flag in the code-behind to determine if it's a postback due to genuine User submit action or by browser 'Refresh'.
Hope this helps!
posted on Wednesday, June 8, 2011 4:34 PM Print