Question

What happens if a long running page is closed by the user before he has received a response?

Does the page continue to run in the it’s thread or is the thread terminated as soon as the user closes the page?

Answer 1

Oded is correct, the request keeps processing long after the user has browsed away or closed their browser window. For fun try this:

protected void Page_Load(object sender, EventArgs e)
{
    for (int count = 0; count < 100; count++)
    {
        Debug.WriteLine("Processing {0}, IsClientConnected={1}", count, Response.IsClientConnected);
        Response.Write(string.Format("Processing {0}<br/>", count));
        Response.Flush();
        Thread.Sleep(1000);
    }
    Response.Write("<h1>Done<h1/>");
}

The request keeps processing after navigating away, but the IsClientConnected property changes to false. You can use this to your advantage, but you have to write code to take advantage of that, normally for long running requests.

Processing 0, IsClientConnected=True
Processing 1, IsClientConnected=True
Processing 2, IsClientConnected=True
Processing 3, IsClientConnected=True
Processing 4, IsClientConnected=True
Processing 5, IsClientConnected=True
Processing 6, IsClientConnected=True
Processing 7, IsClientConnected=True
Processing 8, IsClientConnected=True
Processing 9, IsClientConnected=True
Processing 10, IsClientConnected=True
Processing 11, IsClientConnected=True
Processing 12, IsClientConnected=True
Processing 13, IsClientConnected=False
Processing 14, IsClientConnected=False
Processing 15, IsClientConnected=False
Processing 16, IsClientConnected=False
Processing 17, IsClientConnected=False