c# 事务


     ckd ckd2 = new ckd();
                    ckdsp ckdsp2 = new ckdsp();
                    byte[] bytedatacdk2 = new byte[Marshal.SizeOf(typeof(ckd))];
                    byte[] bytedatacdksp2 = new byte[Marshal.SizeOf(typeof(ckdsp))];
                    FileStream fs2 = new FileStream(FileName, FileMode.Open, FileAccess.Read);
                    string sql1,sql2,sql3;
                   
                    while (fs2.Read(bytedatacdk2, 0, bytedatacdk2.Length) == bytedatacdk2.Length)
                    {                        ckd2 = (ckd)BytesToStuct(bytedatacdk2, typeof(ckd));                        try
                        {
                            sql1;  //insert
                        }
                        catch
                        {
                            continue;
                        }
                        for (int j = 0; j < ckd2.wLength; j++)
                        {                            if (fs2.Read(bytedatacdksp2, 0, bytedatacdksp2.Length) == bytedatacdksp2.Length)
                            {
                                ckdsp2 = (ckdsp)BytesToStuct(bytedatacdksp2, typeof(ckdsp));
                                try
                                {
                                    sql2; //insert
                                }
                                catch
                                {
                                    continue;
                                }
                                try
                                {
                                    sql3; //update
                                }
                                catch
                                {
                                    continue;
                                }
                            }
                        }
                    }
执行完sql1,sql2,sql3才算完成一个事务，怎么给这段代码添加一个事务？