private void btnDR_Click(object sender, EventArgs e)
        {
            string sql = "insert into Seat (CC_LoginId, CC_LoginPassword, CC_UserName) values (@loginId,@loginPassword,@UserName)";
            SqlParameter[] sp =
            {
                new SqlParameter("@loginId",SqlDbType.NVarChar),
                new SqlParameter("@loginPassword",SqlDbType.VarChar),
                new SqlParameter("@UserName",SqlDbType.NVarChar)
            };
            using (FileStream fs = new FileStream(@"D:\Code\20120822\ExeclDemo\bin\Debug\seat.xls", FileMode.Open, FileAccess.Read))
            {
                IWorkbook wk = new HSSFWorkbook(fs);
                ISheet sheet  = wk.GetSheet("seat");
                for (int i = 0; i <= sheet.LastRowNum; i++)
                {
                    IRow row = sheet.GetRow(i);
                    for (int c = 1; c < row.LastCellNum; c++)
                    {
                        ICell cell =row.GetCell(c);
                        sp[c-1].Value=cell.ToString();
                    }
                    SqlHelper.SqlHelper.ExecuteNonQuery(sql,CommandType.Text,sp);
                }
            }
            MessageBox.Show("OK");
        }

使用的是SQLHelper  ...
public  static int ExecuteNonQuery(string sql, CommandType type,params SqlParameter[] parameters)
        {
            
            using (SqlConnection conn = new SqlConnection(con))
            {
                if(conn.State == System.Data.ConnectionState.Closed)
                {
                    conn.Open();
                }
                using (SqlCommand cmd = conn.CreateCommand())
                {
                     = sql;
                     = type;
                    if (parameters != null && parameters.Length > 0)
                    {
                        cmd.Parameters.AddRange(parameters);
                    }
                    cmd.Parameters.Clear();
                    return cmd.ExecuteNonQuery();报错是...另一个SqlParameterCollection中已包含SqlParameter。
                }
            }
        }

改成：
object o = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return o;