命名空间“Microsoft.SqlServer”中不存在类型或命名空间名称“Smo”（您是否缺少程序集引用？）

Question

I want to teke backup of database in windows forms application. I have added References to all 4 ddls

Microsoft.SqlServer.ConnectionInfo.dll
Microsoft.SqlServer.Management.Sdk.Sfc.dll
Microsoft.SqlServer.Smo.dll
Microsoft.SqlServer.SmoExtended.dll

My Code is

using System;
using System.Collections.Generic;
using System.Linq;
using System.Data;
using System.Data.SqlClient;
using System.Text;
using System.Threading.Tasks;
using Microsoft.SqlServer.Server;
using Microsoft.SqlServer.Management.Sdk.Sfc;
using Microsoft.SqlServer.Smo;
using Microsoft.SqlServer.Smo.SmoExtended;


namespace Lodging
{
    class BackupAndRestoreData
    {            
        public static void BackupDatabase(string backUpFile)
        {
            ServerConnection con = new ServerConnection(@"ANI-PC\SQLEXPRESS");
            Server server = new Server(con);
            Backup source = new Backup();
            source.Action = BackupActionType.Database;
            source.Database = "db_Lodge";
            BackupDeviceItem destination = new BackupDeviceItem(backUpFile,
                                                            DeviceType.File);
            source.Devices.Add(destination);
            source.SqlBackup(server);
            con.Disconnect();
        }
        public static void RestoreDatabase(string backUpFile)
        {
            ServerConnection con = new ServerConnection(@"ANI-PC\SQLEXPRESS");
            Server server = new Server(con);
            Restore destination = new Restore();
            destination.Action = RestoreActionType.Database;
            destination.Database = "MyDataBaseName";
            BackupDeviceItem source = new BackupDeviceItem(backUpFile,
                                                           DeviceType.File);
            destination.Devices.Add(source);
            destination.ReplaceDatabase = true;
            destination.SqlRestore(server);
        }
    }
}

This is not giving me error for

using Microsoft.SqlServer.Server;
using Microsoft.SqlServer.Management.Sdk.Sfc;

but gives error :

The type or namespace name 'Smo' does not exist in the namespace 'Microsoft.SqlServer' (are you missing an assembly reference?)

for

using Microsoft.SqlServer.Smo;
using Microsoft.SqlServer.Smo.SmoExtended;

What should I do to remove this error?

Answer 1

using Microsoft.SqlServer.Management.Smo;
using Microsoft.SqlServer.Management.Common;

Try this two namespaces.

The Microsoft.SqlServer.Management.Smo namespace contains the instance object classes that represent SQL Server Database Engine objects and some utility classes that represent specific tasks, such as scripting. When a connection to the instance of the SQL Server Database Engine has been established by using a Server object variable, objects on the instance can be accessed by using the SMO instance objects. For example, you can use the Database object to access databases on the connected instance of SQL Server Database Engine. All the instance classes are related to the Server class in the object hierarchy. Utility classes exist outside of the Server class object hierarchy and represent specific tasks, such as backup or scripting.

Here is link to the article in MSDN

Common is also widely used I recommend you to read about it.

Answer 2

Not sure if this help you, but for the compile error:

The type or namespace name 'XYZ' does not exist in the namespace 'ABC.DEF' (are you missing an assembly reference?)

I found following reasons causing that complation error:

1) If the assembly is targeting later .NET framework(eg 4.5) and you refer the assembly from an application targeting early .NET framework (eg4.0) then you may face this problem.

2) Some times, the "Client Profile" .NET framework projects can't refer to full .NET version assemblies, because Client Profile .NET framework is a strip-down version of .NET framework.

Answer 3

Install SMO

The SQL Server Management Objects (SMO) Framework is a set of objects designed for programmatic management of Microsoft SQL Server and Microsoft Azure SQL Database.

When explicitly targeting a pre-2017 SQL Server version, install the SQL Server Feature Pack (more info in this answer ).

For SQL Server 2017 and above, install SMO as a NuGet package, as per this answer .