1.添加引用
using Microsoft.SqlServer.Management.Smo;
using Microsoft.SqlServer.Management.Common;2.Backup bkpDatabase = new Backup();
// Set the backup type to a database backup
bkpDatabase.Action = BackupActionType.Database;
// Set the database that we want to perform a backup on
bkpDatabase.Database = DbName;// cmbDatabase.SelectedItem.ToString();
// Set the backup device to a file
//new BackupDeviceItem(saveBackupDialog.FileName, DeviceType.File);
BackupDeviceItem bkpDevice = new BackupDeviceItem(NewName, DeviceType.File);
// Add the backup device to the backup
bkpDatabase.Devices.Add(bkpDevice);
// Perform the backup
bkpDatabase.SqlBackup(SD.SrvSql);
File.Copy(Source, PathDestination + "\\" + fileName);
File.Delete(Source);
详细参见MSDN
https://msdn.microsoft.com/en-us/library/ms162133(v=sql.120).aspx
http://sridharbabuk.blogspot.com/2009/07/sql-server-database-backups-using-smo.html