c# - "The ConnectionString property is invalid."当我知道它是有效的

Question

我有一个 ASP.NET MVC 应用程序，其中的数据库位于 IBM i 系列服务器上。当我开始收到 The ConnectionString property is invalid. 错误时，我的应用程序开发接近完成:

1. 仅在登录时
2. 重建后首次成功登录后
3. 任何登录的人仍然可以正常工作

另请注意，此问题仅出现在我的解决方案中的一个项目中。另一个项目使用完全相同的连接字符串并且没有这个问题(复制并粘贴以确保 100%)。我正在积极开发这些项目，但在登录后没有接触连接字符串，也没有使用 AccountController 和相关模型类。

我使用的是 Visual Studio 2008 和 .NET 3.5 版。

连接字符串:

<connectionStrings>
    <add name="IbmIConnectionString" connectionString="DataSource=192.168.50.200;DefaultCollection=QMFILES;Naming=sql;UserID=XXX;Password=XXXX;"/>
</connectionStrings>

帐户 Controller 登录方法:

    [HttpPost]
    public ActionResult LogOn(LogOnModel model, string returnUrl)
    {
        string fullName = String.Empty;
        string employeeId = String.Empty;

        if (ModelState.IsValid)
        {
            if (MembershipService.ValidateUser(model.UserName, model.Password))
            {
                FormsService.SignIn(model.UserName, model.RememberMe);
                EmployeeLoginModel elm = new EmployeeLoginModel();
                elm.GetUserInfo(model.UserName, model.Password, out fullName, out employeeId);
                // Update the AuthCookie to include the last 4 digits of the SSN.
                string userDataString = String.Format("{0}|{1}|{2}", model.Password, fullName.Trim(), employeeId.Trim());
                HttpCookie authCookie = FormsAuthentication.GetAuthCookie(model.UserName, model.RememberMe);
                FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(authCookie.Value);
                FormsAuthenticationTicket newTicket = new FormsAuthenticationTicket(ticket.Version, ticket.Name, ticket.IssueDate, ticket.Expiration, ticket.IsPersistent, userDataString);
                authCookie.Value = FormsAuthentication.Encrypt(newTicket);
                Response.Cookies.Add(authCookie);

                if (!String.IsNullOrEmpty(returnUrl))
                {
                    return Redirect(returnUrl);
                }
                else
                {
                    return RedirectToAction("Index", "Home");
                }
            }
            else
            {
                ModelState.AddModelError("", "The user name or password provided is incorrect.");
            }
        }

        // If we got this far, something failed, redisplay form
        return View(model);
    }

员工登录模型:

public class EmployeeLoginModel
{
    public string UserName { set; get; }
    public string Password { set; get; }

    private iDB2Connection conn;

    /// <summary>
    /// Initializes a new instance of the <see cref="EmployeeLoginModel"/> class.
    /// </summary>
    public EmployeeLoginModel()
    {
        conn = new iDB2Connection(ConfigurationManager.ConnectionStrings["IbmIConnectionString"].ConnectionString);
    }

    /// <summary>
    /// Determines whether [is valid user] [the specified username].
    /// </summary>
    /// <param name="username">The username.</param>
    /// <param name="password">The password.</param>
    /// <returns>
    ///     <c>true</c> if [is valid user] [the specified username]; otherwise, <c>false</c>.
    /// </returns>
    public bool IsValidUser(string username, string password)
    {
        int count = 0;

        // Get the data from the iSeries
        using (conn)
        {
            string sqlStatement = "SELECT COUNT(XXXXX) FROM XXXXX WHERE UPPER(XXXXXX) = @1 AND XXXXXX = @2";

            iDB2Command cmd = new iDB2Command(sqlStatement, conn);
            cmd.CommandType = CommandType.Text;
            cmd.Parameters.Add("@1", username.ToUpper());
            cmd.Parameters.Add("@2", password);
            conn.Open();
            count = (Int32)cmd.ExecuteScalar();
            conn.Close();
        }

        return ((count == 0) ? false : true);
    }

Answer 1

出现此错误的另一个非常微不足道的原因是未安装所需的 DB2 驱动程序。

内部异常说明

Unable to load DLL 'cwbdc.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E) Type: System.DllNotFoundException