Why Response.Redirect causes System.Threading.ThreadAbortException?

Question

When I use Response.Redirect(...) to redirect my form to a new page I get the error:

A first chance exception of type \'System.Threading.ThreadAbortEx

Answer 1

I know I'm late, but I've only ever had this error if my Response.Redirect is in a Try...Catch block.

Never put a Response.Redirect into a Try...Catch block. It's bad practice

As an alternative to putting the Response.Redirect into the Try...Catch block, I'd break up the method/function into two steps.

1. inside the Try...Catch block performs the requested actions and sets a "result" value to indicate success or failure of the actions.

2. outside of the Try...Catch block does the redirect (or doesn't) depending on what the "result" value is.

This code is far from perfect and probably should not be copied since I haven't tested it.

public void btnLogin_Click(UserLoginViewModel model)
{
    bool ValidLogin = false; // this is our "result value"
    try
    {
        using (Context Db = new Context)
        {
            User User = new User();

            if (String.IsNullOrEmpty(model.EmailAddress))
                ValidLogin = false; // no email address was entered
            else
                User = Db.FirstOrDefault(x => x.EmailAddress == model.EmailAddress);

            if (User != null && User.PasswordHash == Hashing.CreateHash(model.Password))
                ValidLogin = true; // login succeeded
        }
    }
    catch (Exception ex)
    {
        throw ex; // something went wrong so throw an error
    }

    if (ValidLogin)
    {
        GenerateCookie(User);
        Response.Redirect("~/Members/Default.aspx");
    }
    else
    {
        // do something to indicate that the login failed.
    }
}