17章 QQ用户信息管理系统1-2

using System; using System.Collections.Generic; using System.Data.SqlClient; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleApplication1 { class UserManager { private DBHandle _dbHandle = new DBHandle(); const String ERRMSG = "数据操作失败！"; const String EXCEPT = "出现异常。请与系统管理员联系！"; public void Lofin() { int count = 0; do{ string strUserName = string.Empty;//初始化管理员登录名 string strPwd = string.Empty;//初始化管理员密码 count++; Console.WriteLine("请输入用户名："); strUserName = Console.ReadLine(); Console.WriteLine("请输入密码："); strPwd = Console.ReadLine(); if (strUserName.Equals(string.Empty) || strPwd.Equals(string.Empty)) { Console.WriteLine("输入错误，请重新输入！\n"); continue;//重新输入用户名和密码 } else { // 需返回的结果信息 string strMsg = string.Empty; //数据库验证 bool bRet = _dbHandle.CheckAdminInfo(strUserName, strPwd, ref strMsg); if (bRet) { Console.WriteLine("登录成功！"); // 显示菜单 ShowMenu(); break;//退出程序 } else { Console.WriteLine("登录失败：" + strMsg + "\n"); continue;//重新输入用户名和密码 } } }while(count<3); if(count==3){ Console.WriteLine("\n连续三次登陆失败,退出本系统!\n"); } } private void ShowMenu() { do{ Console.WriteLine(""); Console.WriteLine("=======欢迎登录QQ用户信息管理系统======"); Console.WriteLine("----------------请选择菜单项----------"); Console.WriteLine("1、显示用户清单"); Console.WriteLine("2、更新在线天数"); Console.WriteLine("3、添加用户新记录"); Console.WriteLine("4、更新用户等级"); Console.WriteLine("5、删除用户记录"); Console.WriteLine("0、退出"); Console.WriteLine("======================================="); int option =int.Parse(Console.ReadLine()); switch (option) { case 1://显示用户信息 ShowUserInfo(); continue; case 2://更新在线天数 UpdateOnLineDay(); continue; case 3://添加用户 continue; case 4://更新用户等级 continue; case 5://删除用户 continue; case 0: if (option==0) { break;//退出 } else { continue; } default: continue; } break; }while (true); } private void ShowUserInfo() { SqlDataReader reader = _dbHandle.GetUserList(); if (reader==null) { Console.WriteLine(EXCEPT); return; } DisplayUserInfo(reader); } private void DisplayUserInfo(SqlDataReader reader) { Console.WriteLine("--------------------------------------------------------------------------------"); Console.WriteLine("编号\t昵称\t\t等级\t\t邮箱\t\t在线天数"); Console.WriteLine("--------------------------------------------------------------------------------"); while (reader.Read()) { Console.Write(reader["UserId"] + "\t"); Console.Write(reader["UserName"] + "\t"); Console.Write(ShowDesign((String)reader["LevelName"]) + "\t\t"); Console.Write(reader["Email"] + "\t"); Console.WriteLine(reader["OnLineDay"]); } Console.WriteLine("--------------------------------------------------------------------------------"); } private string ShowDesign(string strLevel) { string strDesign = string.Empty; switch (strLevel) { case "无等级": strDesign = "―"; break; case "星星": strDesign = "☆"; break; case "月亮": strDesign = "€"; break; case "太阳": strDesign = "◎"; break; default: break; } return strDesign; } /// <summary> /// 更新在线天数 /// </summary> private void UpdateOnLineDay() { try { Console.WriteLine("请输入用户编号："); int iUserId = Convert.ToInt32(Console.ReadLine()); Console.WriteLine("请输入新的在线天数"); double iNewOnlineDay = Convert.ToDouble(Console.ReadLine()); int iRet = _dbHandle.UpdateOnlineDay(iUserId,iNewOnlineDay); if (iRet == -1) Console.WriteLine(ERRMSG); else if (iRet == 0) { Console.WriteLine("用户记录不存在"); } else { Console.WriteLine("修改成功！"); } } catch (Exception) { Console.WriteLine(EXCEPT); } } } } using System; using System.Collections.Generic; using System.Data.SqlClient; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleApplication1 { class DBHandle { //连接字符串 private const string strConn = @"Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; /// <summary> /// 登陆 /// </summary> /// <param name="UserName"></param> /// <param name="UserPwd"></param> /// <param name="strMsg"></param> /// <returns></returns> public bool CheckAdminInfo(string UserName,string UserPwd,ref string strMsg) { SqlConnection conn = new SqlConnection(strConn); try { //sql 语句 string str = @"SELECT COUNT(*) FROM [QQDB].[dbo].[admin] where LoginId='"+UserName+"'and LoginPwd='"+UserPwd+"'"; //打开数据库 conn.Open(); //创建command命令 SqlCommand comm = new SqlCommand(str, conn); int i = (int)comm.ExecuteScalar(); if (i != 1) { strMsg = "输入无效!"; return false; } else { return true; } } catch (Exception ex) { Console.WriteLine(ex.Message); strMsg = "发生异常!"; return false; } finally { conn.Close(); } } /// <summary> /// 取得学生列表 /// </summary> /// <returns></returns> public SqlDataReader GetUserList() { try { SqlConnection conn = new SqlConnection(strConn); conn.Open(); string sql = @"select a.UserId, a.UserName, b.LevelName, a.Email, a.OnLineDay from UserInfo a, Level b where a.LevelId=b.LevelId"; SqlCommand comm = new SqlCommand(sql, conn); return comm.ExecuteReader(); } catch (Exception e) { Console.WriteLine(e); return null; } } public int UpdateOnlineDay(int userId, double newOnlineDay) { SqlConnection conn = new SqlConnection(strConn); string sql = "update UserInfo set OnLineDay='" + newOnlineDay + "' where UserId=" + userId + ""; try { conn.Open(); SqlCommand comm = new SqlCommand(sql, conn); return comm.ExecuteNonQuery(); } catch (Exception e) { Console.WriteLine(e); return -1; } } } } using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { UserManager s = new UserManager(); s.Lofin(); Console.ReadLine(); } } }