//首先还是要using system.io;    
        public void Write(ArrayList log)
            {
                      //将文件保存在桌面，文件名称为当前时间.txt
                FileStream fs = new
                                  FileStream("C:\Users\ailin\Desktop\" +
                                  DateTime.Now.ToLongTimeString().Replace(":", "") + ".txt", FileMode.OpenOrCreate, FileAccess.ReadWrite);
                    StreamWriter sw = new StreamWriter(fs, Encoding.Default);
                    foreach( string i in log)
                    {

                            sw.Write(i.ToString());

                    }
                     DateTime dt1 = DateTime.Now;
                     sw.WriteLine();
                     sw.WriteLine("操作人：cxx");
                     sw.WriteLine("日期："+Convert.ToString(dt1));
                     sw.Flush();
                     sw.Close();
            }

            //string sSaveExcelName =
        //"C:\" + DateTime.Now.ToShortDateString().Replace("-", "") + DateTime.Now.ToLongTimeString().Replace(":", "") + ".xls";
         public static ArrayList aChg_Slab_Len = new ArrayList();
            private void button2_Click(object sender, EventArgs e)
            {

                    ArrayList cx = new ArrayList();

                    for (int i = 0; i < ss1.ActiveSheet.RowCount; i++)
                    {
                        for (int j = 0; j < ss1.ActiveSheet.ColumnCount; j++)
                        {
                           cx.Add(ss1.ActiveSheet.Cells[i, j].Text);
                           cx.Add("  ");
                        }
                        cx.Add("rn");

                    }
                    //执行导出日志的操作
                    Write(cx);
                    return;

            }