I know how to use C# and SMO to create a file backup on a SQL Server:
public void BackupDatabase(Microsoft.SqlServer.Management.Smo.Server server,
string databaseName, string backupFilename,
string backupName, string backupDescription) {
Backup backup = new Backup();
backup.Devices.AddDevice(backupFilename, DeviceType.File);
backup.Database = databaseName;
backup.Action = BackupActionType.Database;
backup.BackupSetDescription = backupDescription;
backup.BackupSetName = backupName;
backup.Incremental = false;
backup.LogTruncation = BackupTruncateLogType.Truncate;
backup.Initialize = true; // supposed to overwrite
backup.SqlBackup(server);
}
What I don't know (and can't find) is how to add the file BackupDevice to the SQL server.