System.Data.SqlClient.SqlException: 在与 SQL Server 建立连接时出现与网络相关的或特定于实例的错误。未找到或无法访问服务器。请验证实例名称是否正确并且 SQL Server 已配置为允许远程连接。 (provider: TCP 提供程序, error: 0 - 由于连接方在一段时间后没有正确答复或连接的主机没有反应,连接尝试失败。) 在 System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) 在 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) 在 System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject) 在 System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) 在 System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) 在 System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) 在 System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) 在 System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) 在 System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) 在 System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) 在 System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) 在 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) 在 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) 在 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) 在 System.Data.SqlClient.SqlConnection.Open() 在 mySql.DsSql(String Sqlstr) 位置 d:\wwwroot\zsbaisha\wwwroot\App_Code\mySql.cs:行号 65