使用 DataReader 从 SQL 访问数据

我在 c# 中的数据库是这样的

    static SqlConnection cnn;
    static SqlDataReader reader;
    public string StorePass;
    public string  pass;
    byte[] tmpSource;
    byte[] tmpHash;
    public int  user;
    //static ArrayList list;
    static string connect = @"Server=.;database=Intranet;Integrated Security=true";
    public static void open()
    {
        cnn = new SqlConnection();
        cnn.ConnectionString = connect;
        try
        {
            cnn.Open();
        } //open connection
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
            Console.WriteLine(e.Source);
            Console.WriteLine("unable to open");
        }
    }
    public bool login(int usr, string pass)
    {
        user = usr;
        this.pass = pass;
        string temppass;
        tmpSource = ASCIIEncoding.ASCII.GetBytes(pass);
        tmpHash = new MD5CryptoServiceProvider().ComputeHash(tmpSource);
        temppass = ByteArrayToString(tmpHash);
        DB.open();
        StorePass = DB.retrievePass(user);
        bool bEqual = false;
        bEqual = String.Equals(temppass, StorePass, StringComparison.Ordinal);
        if (bEqual)
        {
            return true; 
        }
    }
    static string ByteArrayToString(byte[] arrInput)
    {
        int i;
        StringBuilder sOutput = new StringBuilder(arrInput.Length);
        for (i = 0; i < arrInput.Length - 1; i++)
        {
            sOutput.Append(arrInput[i].ToString("X2"));
        }
        return sOutput.ToString();
    }
    private static string retrievePass(int user)
    {
        using (cnn)
        {
            string pass = "";
            string table = "Login_Table";
            string strSQL = string.Format("Select * From {0} where UID = '{1}'", table, user);
            SqlCommand myCommand = new SqlCommand(strSQL, cnn);
            cnn.Open();
            reader = myCommand.ExecuteReader();
            /*while (reader.Read())
            {
                pass = reader["Hashed_Password"].ToString();
            }*/
            try
            {
                reader.Read();
                pass = reader["Hashed_Password"].ToString();
                reader.Close();
                return pass;
            }
            catch
            {
                reader.Close();
                return null;
            }
        }
    }  

我的aspx.cs来自我调用上述方法访问的网站是

    DB ob;
protected void Page_Load(object sender, EventArgs e)
{
    ob = new DB();
    DB.open();
}
protected void Login1_Authenticate(object sender, AuthenticateEventArgs e)
{
    try
    {
        int id = int.Parse(Login1.UserName);
        string pass = Login1.Password;
        if (ob.login(id, pass))
        {
            Session["user"] = ob;
            this.Session["UserName"] = Login1.UserName;
            Response.Redirect("Post_View.aspx");
        }
    }
    catch(Exception ex)
    {
        throw;
    }
}
protected void LoginButton_Click(object sender, EventArgs e)
{
}

上面的代码在可视化工作室中模拟得很好。但是，在 IIS 8 中部署时，它显示用户"IIS APPPOOL''.NET v2.0"的错误登录失败。请帮助我，因为其他代码也写在类似的代码中，在IIS中部署时显示错误。我是否必须更改我的代码？提前致谢

我的堆栈跟踪

      Server Error in '/Test' Application.
     Login failed for user 'IIS APPPOOL'.NET v2.0'.
   Description: An unhandled exception occurred during the execution of the current web     request. Please review the stack trace for more information about the error and where it originated in the code. 
   Exception Details: System.Data.SqlClient.SqlException: Login failed for user 'IIS APPPOOL'.NET v2.0'.
  Source Error: 

 Line 80:                 string strSQL = string.Format("Select * From {0} where UID = '{1}'", table, user);
 Line 81:                 SqlCommand myCommand = new SqlCommand(strSQL, cnn);
 Line 82:                 cnn.Open();
 Line 83:                 reader = myCommand.ExecuteReader();
 Line 84:                 /*while (reader.Read())
 Source File: e:'Demo'Intranet_DB'Intranet_DB'DB.cs    Line: 82 
 Stack Trace: 

 [SqlException (0x80131904): Login failed for user 'IIS APPPOOL'.NET v2.0'.]
 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +578
 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +88
 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +6322807
 System.Data.SqlClient.SqlConnection.Open() +258
 Intranet_DB.DB.retrievePass(Int32 user) in e:'Demo'Intranet_DB'Intranet_DB'DB.cs:82
 Intranet_DB.DB.login(Int32 usr, String pass) in    e:'Demo'Intranet_DB'Intranet_DB'DB.cs:51
  _Default.Login1_Authenticate(Object sender, AuthenticateEventArgs e) in c:'inetpub'wwwroot'Test'Default.aspx.cs:38
    System.Web.UI.WebControls.Login.AttemptLogin() +152
    System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +124
    System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +70
    System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +29
    System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2981