.NET Framework 4.5.2+
.NET Framework 4.5.2+
.NET Standard 2.0+

MSSqlConnectionProvider.GetConnectionStringWithAttach(String, String, Boolean) Method

Returns a connection string to connect to a MS SQL Server database by attaching a specified .mdf database file to a specific server using Windows Integrated Security.

Namespace: DevExpress.Xpo.DB

Assembly: DevExpress.Xpo.v21.1.dll


public static string GetConnectionStringWithAttach(
    string server,
    string attachDbFilename,
    bool userInstance


Name Type Description
server String

A string that specifies the SQL server name.

attachDbFilename String

A string specifying a .mdf database file to attach to the server. This value is used to initialize the “AttachDbFilename” field of the connection string.

userInstance Boolean

true to enable User Instances (required when attaching the attachDbFilename); otherwise, false (when the database specified by the attachDbFilename already exists on the server). For more information about SQL Server Express and User Instances, read the SQL Server 2005 Express Edition User Instances MSDN article.


Type Description

A connection string.



This method is in effect only for SQL Server 2005 Express Edition databases.

The method enables Integrated Security in the resulting connection string. To connect using specific login credentials (user name and password), call the other GetConnectionStringWithAttach overloaded method.

See Also