我不能没有失败地使用角色。 “发生与网络相关或特定于实例的错误”

Question

Hi I'm trying to use and understand Roles for the first time. How can I resolve this? Do I need to add something to the WebConfig ?

private static void CreateRoleIfNotExists(string role)
{
    if (!Roles.RoleExists(role)) // this line throws the error.
    {
        Roles.CreateRole(role);
    }  
}

Update, complete stacktrace inserted below:

[SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)] System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +4856727 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +194 System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject) +4867325 System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +90 System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +374 System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +225 System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +189 System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +4868451 System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +31 System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +431 System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +499 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +65 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +117 System.Data.SqlClient.SqlConnection.Open() +122 System.Web.DataAccess.SqlConnectionHolder.Open(HttpContext context, Boolean revertImpersonate) +87 System.Web.DataAccess.SqlConnectionHelper.GetConnection(String connectionString, Boolean revertImpersonation) +221 System.Web.Security.SqlRoleProvider.RoleExists(String roleName) +478 System.Web.Security.Roles.RoleExists(String roleName) +73 dk.certifikat.Global.CreateRoleIfNotExists(String role)

Answer 1

If you use the standard .net membership providers and roleproviders you need to setup the aspnetdb

this can be done by a command from the commandprompt

aspnet_regsql

this can be found in you .net framework directory. If you did this. You need to provide the application with an connectionstring to the database where the aspnetdb is running.

more about this can be found here .

Answer 2

I also encountered this error. I was following the example at http://www.asp.net/web-forms/tutorials/aspnet-45/getting-started-with-aspnet-45-web-forms/introduction-and-overview in which they also use Roles.RoleExists at some moment. When I ran the application locally with Visual Studio Express, everything worked fine. But when I tried to access the application via the web, I got the same connection error.

Turned out I had to change the web.config file. I changed the DefaultProfileProvider, DefaultMembershipProvider and DefaultRoleProvider. I changed the connectionStringName attribute to the one I had added to the connectionStrings, namely:

<add name="WingtipToys" providerName="System.Data.SqlClient" connectionString="Server=.\SQLEXPRESS;Database=wingtiptoys;Integrated Security=False;User Id=wingtiptoys;Password=wingtiptoys;AttachDbFileName=|DataDirectory|wingtiptoys.mdf;Persist Security Info=False" />

For example, the DefaultMembershipProvider now looks like:

<add name="DefaultMembershipProvider" type="System.Web.Providers.DefaultMembershipProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="WingtipToys" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="/" />

with connectionStringName="WingtipToys" instead of connectionStringName="DefaultConnection"

And then everything worked fine. This may not be the best solution, but I hope this answer can help somebody.