c# - 'System.Threading.ThreadAbortException' 发生在 mscorlib.dll 和线程'' (0x11a8) 以代码 0 (0x0) 退出

Question

我有四个学生数据库，教师，非教师和管理员，在登录页面上我有一个用于输入的用户 ID 和密码文本框以及用户类型下拉列表......我在登录页面上添加他们的姓名会话显然，当我在我的输出控制台和母版页上 debug.write 它时，它显示了所有四个用户的名称，因此我猜会话也是在那里创建的......我的母版页代码如下：

if (Session["StudFirstName"] != null)
    {
        Label1.Text = Session["StudId"].ToString();
    }

    if (Session["FacultyFirstName"] != null)
    {
        Label1.Text = Session["StudId"].ToString();
    }
    if (Session["AccEmployeeName"] != null)
    {
        Label1.Text = Session["StudId"].ToString();
    }
    if (Session["AdminName"] != null)
    {
        Label1.Text = Session["StudId"].ToString();
    }

    else
    {
        Response.Redirect("Login.aspx");
    }

但是当我在浏览器上运行它并在登录页面上点击提交时，正如我所说的会话已创建但页面永远不会进入母版页，它只是刷新并自行登录，我也试图清除 nullexceptions...怎么能我解决了这个异常？？并问我是否需要更多信息.... :)

这是我的提交按钮代码：

if (DropDownList1.SelectedItem.Text == "Student")
    {
        SqlConnection con = new SqlConnection(strcon);
        SqlCommand cmd = new SqlCommand("Select StudFirstName from Student where StudId=@sid and Password=@pw", con);
        cmd.Parameters.AddWithValue("@sid", TextBox1.Text);
        cmd.Parameters.AddWithValue("@pw", TextBox2.Text);
        con.Open();
        string name = Convert.ToString(cmd.ExecuteScalar());
        con.Close();

        if (String.IsNullOrEmpty(name))
            Label1.Text = "Sorry! Invalid User ID or Password!";
        else
        {
            if (CheckBox1.Checked)
            {
                Response.Cookies["UName"].Value = TextBox1.Text;
                Response.Cookies["PWD"].Value = TextBox2.Text;
                Response.Cookies["UName"].Expires = DateTime.Now.AddMonths(2);
                Response.Cookies["PWD"].Expires = DateTime.Now.AddMonths(2);
            }

            Session.Add("studid", TextBox1.Text);
            Session.Add("studfirstname", name);
            FormsAuthentication.RedirectFromLoginPage(name, false);
            Debug.Write(Session["studfirstname"].ToString());
        }

}







     if (DropDownList1.SelectedItem.Text == "Faculty Staff")
    {
        SqlConnection con = new SqlConnection(strcon);
        SqlCommand cmd = new SqlCommand("Select FacultyFirstName from Faculty where FacultyId=@fid and Password=@pw", con);
        cmd.Parameters.AddWithValue("@fid", TextBox1.Text);
        cmd.Parameters.AddWithValue("@pw", TextBox2.Text);
        con.Open();
        string name = Convert.ToString(cmd.ExecuteScalar());
        con.Close();
        if (String.IsNullOrEmpty(name))
            Label1.Text = "Sorry! Invalid User ID or Password!";
        else
        {
            if (CheckBox1.Checked)
            {
                Response.Cookies["UName"].Value = TextBox1.Text;
                Response.Cookies["PWD"].Value = TextBox2.Text;
                Response.Cookies["UName"].Expires = DateTime.Now.AddMonths(2);
                Response.Cookies["PWD"].Expires = DateTime.Now.AddMonths(2);
            }
            Session["FacultyId"] = TextBox1.Text;
            Session.Add("FacultyFisrtName", name);
            FormsAuthentication.RedirectFromLoginPage(name, false);
            Debug.Write(Session["FacultyFisrtName"].ToString());
        }
    }
    if (DropDownList1.SelectedItem.Text == "Non-Faculty Staff")
    {
        SqlConnection con = new SqlConnection(strcon);
        SqlCommand cmd = new SqlCommand("Select AccEmployeeName from AccEmployee where AccEmployeeId=@aid and Password=@pw", con);
        cmd.Parameters.AddWithValue("@aid", TextBox1.Text);
        cmd.Parameters.AddWithValue("@pw", TextBox2.Text);
        con.Open();
        string name = Convert.ToString(cmd.ExecuteScalar());
        con.Close();
        if (String.IsNullOrEmpty(name))
            Label1.Text = "Sorry! Invalid User ID or Password!";
        else
        {
            if (CheckBox1.Checked)
            {
                Response.Cookies["UName"].Value = TextBox1.Text;
                Response.Cookies["PWD"].Value = TextBox2.Text;
                Response.Cookies["UName"].Expires = DateTime.Now.AddMonths(2);
                Response.Cookies["PWD"].Expires = DateTime.Now.AddMonths(2);
            }
            Session["AccEmployeeFacultyId"] = TextBox1.Text;
            Session.Add("AccEmployeeName", name);
            FormsAuthentication.RedirectFromLoginPage(name, false);
            Debug.Write(Session["AccEmployeeName"].ToString());
        }
    }
    if (DropDownList1.SelectedItem.Text == "Admin")
    {
        SqlConnection con = new SqlConnection(strcon);
        SqlCommand cmd = new SqlCommand("Select AdminName from Admin where AdminId=@pid and Password=@pw", con);
        cmd.Parameters.AddWithValue("@pid", TextBox1.Text);
        cmd.Parameters.AddWithValue("@pw", TextBox2.Text);
        con.Open();
        string name = Convert.ToString(cmd.ExecuteScalar());
        con.Close();
        if (String.IsNullOrEmpty(name))
            Label1.Text = "Sorry! Invalid User ID or Password!";
        else
        {
            if (CheckBox1.Checked)
            {
                Response.Cookies["UName"].Value = TextBox1.Text;
                Response.Cookies["PWD"].Value = TextBox2.Text;
                Response.Cookies["UName"].Expires = DateTime.Now.AddMonths(2);
                Response.Cookies["PWD"].Expires = DateTime.Now.AddMonths(2);
            }
            Session["AdminId"] = TextBox1.Text;
            Session.Add("AdminName", name);
            FormsAuthentication.RedirectFromLoginPage(name, false);
            Debug.Write(Session["AdminName"].ToString());
                        }
    }