使用三层的思想实现登陆
题目:做一个登陆窗口,实现登陆。登陆成功后实现修改密码的功能。在登陆过程中,判断用户名或密码是否正确,修改
密码时判断两次密码是否相等,原密码是否正确。(密码使用MD5加密算法)
要求:使用三层的思想去实现该功能。(UI,DAL,BLL)
截图如下:
1、DAL层程序如下:
// sqlHelper.cs
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data; using System.Data.SqlClient; using System.Configuration; namespace 简单的三层.DAL { public class SqlHelper { private static readonly string connstr = ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString; // 增删查改 public static int ExecNoquary(string sql, CommandType comtype, params SqlParameter[] pms) { using (SqlConnection con = new SqlConnection(connstr)) { using (SqlCommand com = new SqlCommand(sql, con)) { com.CommandType = comtype; if (pms != null) { com.Parameters.AddRange(pms); } con.Open(); return com.ExecuteNonQuery(); } } } // 返回一条数据 public static object ExecSalary(string sql, CommandType comtype, params SqlParameter[] pms) { using (SqlConnection con = new SqlConnection(connstr)) { using (SqlCommand com = new SqlCommand(sql, con)) { com.CommandType = comtype; if (pms != null) { com.Parameters.AddRange(pms); } con.Open(); return com.ExecuteScalar(); } } } // 返回SqlDataReader public static SqlDataReader ExectureReader(string sql, CommandType cmdType, params SqlParameter[] pms) { SqlConnection con = new SqlConnection(connstr); using (SqlCommand com = new SqlCommand(sql, con)) { com.CommandType = cmdType; if (pms != null) { com.Parameters.AddRange(pms); } try { con.Open(); return com.ExecuteReader(CommandBehavior.CloseConnection); } catch { con.Close(); con.Dispose(); throw; } } } } }
// T_SeatDal.cs using System; using System.Collections.Generic; using System.Data; using System.Data.SqlClient; using System.Linq; using System.Text; using 简单的三层.Model; namespace 简单的三层.DAL { class T_SeatDal { public int Login(string loginId, string password) { string sql = "select count(*) from T_Seats where CC_LoginId=@Id and CC_LoginPassword=@pwd"; SqlParameter[] pms = new SqlParameter[] { new SqlParameter("@Id",loginId), new SqlParameter("@pwd",password) }; return (int)SqlHelper.ExecSalary(sql,CommandType.Text,pms); } public T_Seat GetUserBasicInfoByLogininId(string uid) { T_Seat model = null; string sql = "select cc_autoid,cc_loginpassword,cc_username from T_Seats where CC_LoginId=@uid"; using (SqlDataReader reader = SqlHelper.ExectureReader(sql, System.Data.CommandType.Text, new SqlParameter("@uid",uid))) { if (reader.HasRows) { if (reader.Read()) { model = new T_Seat(); model.CC_AutoId = reader.GetInt32(0); model.CC_LoginPassword = reader.GetString(1); model.CC_UserName = reader.GetString(2); } } } return model; // 如果没有查询到数据则返回null } // 校验旧密码 public int CheckOldPassword(int autoid, string oldPwd) { string sql = "select count(*) from T_Seats where CC_AutoId=@autoId and CC_LoginPassword=@oldPwd"; SqlParameter[] pms = new System.Data.SqlClient.SqlParameter[] { new SqlParameter("@autoId",autoid), new SqlParameter("@oldPwd",oldPwd) }; return (int)SqlHelper.ExecSalary(sql,CommandType.Text,pms); } //修改密码 public int UpdatePassword(int autoId, string newPwd) { string sql = "Update T_Seats set CC_LoginPassword=@newpwd where CC_AutoId=@autoId"; SqlParameter[] pms = new System.Data.SqlClient.SqlParameter[] { new SqlParameter("@newpwd",newPwd), new SqlParameter("@autoId",autoId) }; return SqlHelper.ExecNoquary(sql, System.Data.CommandType.Text,pms); } } }
// TblPerHelper.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data; using System.Data.SqlClient; namespace 简单的三层.DAL { class TblPerHelper { public bool UpdatePerson(int autoId) { string strsql = "update Person set Age = Age+1 where ID=@id"; SqlParameter[] pms = new SqlParameter[] { new SqlParameter("@id",autoId) }; return SqlHelper.ExecNoquary(strsql,CommandType.Text,pms)>0; } } }
2、BLL层
// CommonHelper.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Security.Cryptography; namespace 简单的三层.BLL { class CommonHelper { public static string GetMD5FormString(string msg) { // 1.创建一个用来计算MD5值的类的对象 using (MD5 md5 = MD5.Create()) { // 把字符串转换为byte[] // 注意如果字符中包含汉字使用utf-8编码转换为byte[],当其他地方计算MD5值的时候,如果汉字使用了不同的编码,同样的汉字生成的byte[]也是不一样的,所以计算出来的MD5值也是不一样的 byte[] msgBuffer = Encoding.Default.GetBytes(msg); // 2.计算给定字符串的MD5值 // 返回值就是计算后的MD5值,如何把一个长度为16的byte[]数组转换为一个长度为32的字符串:就是把每个byte转成16进制同时保留2位即可 byte[] md5Buffer = md5.ComputeHash(msgBuffer); md5.Clear(); StringBuilder sbMd5 = new StringBuilder(); for (int i = 0; i < md5Buffer.Length; i++) { sbMd5.Append(md5Buffer[i].ToString("x2")); } return sbMd5.ToString(); } } } }
//T_SeatsBll.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using 简单的三层.DAL; using 简单的三层.Model; namespace 简单的三层.BLL { class T_SeatsBll { T_SeatDal dal = new T_SeatDal(); public bool Login(string loginId, string passWord) { return dal.Login(loginId,CommonHelper.GetMD5FormString(passWord))>0; } public loginState CheckUserLogin(string loginId,string password,out T_Seat model) { model = dal.GetUserBasicInfoByLogininId(loginId); if (model == null) { return loginState.UserNotExits; } else if (model.CC_LoginPassword == CommonHelper.GetMD5FormString(password)) { return loginState.Success; } else { return loginState.ErrorPassWord; } } public ChangePasswordResult ChangePassWord(int autoId,string oldPwd,string newPwd1,string newPwd2) { // 校验两次输入的新密码 if (CheckPassword(newPwd1, newPwd2)) { // 校验旧密码 if (CheckOldPassWord(autoId, oldPwd)) { // 如果旧密码正确,那么执行修改密码操作 if (dal.UpdatePassword(autoId,CommonHelper.GetMD5FormString(newPwd1)) > 0) { return ChangePasswordResult.Succeed; } else { return ChangePasswordResult.Faild; } } else { return ChangePasswordResult.ErrorOldPassword; } } else { return ChangePasswordResult.DiffNewPassword; } } // 校验两次新密码是否一致 public bool CheckPassword(string new1, string new2) { return new1 == new2; } private bool CheckOldPassWord(int autoid,string oldPwd) { return dal.CheckOldPassword(autoid,CommonHelper.GetMD5FormString(oldPwd))>0; } } //修改密码的枚举 public enum ChangePasswordResult { DiffNewPassword, ErrorOldPassword, Succeed, Faild } // 用户登陆结果 public enum loginState { Success, UserNotExits, ErrorPassWord } }
//TblPerBll.cs using System; using 简单的三层.DAL; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace 简单的三层.BLL { class TblPerBll { public bool IncreAge(int autoId) { TblPerHelper per = new TblPerHelper(); if (per.UpdatePerson(autoId)) { return true; } else { return false; } } } }
3.UI层
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; using 简单的三层.BLL; using 简单的三层.Model; namespace 简单的三层.UI { public partial class frmLogin2 : Form { public frmLogin2() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { // 采集数据 string uid = tB_Login.Text.Trim(); string password = tB_Pwd.Text; // 调用业务逻辑数据 T_SeatsBll bll = new T_SeatsBll(); T_Seat model = null; loginState state = bll.CheckUserLogin(uid,password,out model); switch (state) { case loginState.Success: MessageBox.Show("Ok"); // 记录当前用户的Id GlobalHelper.auto_id = model.CC_AutoId; label3.Text = model.CC_UserName; btn_ChangePassWord.Enabled = true; break; case loginState.UserNotExits: MessageBox.Show("User nit exits"); break; case loginState.ErrorPassWord: MessageBox.Show("Error password"); break; default: break; } } // 点击修改密码 private void btn_ChangePassWord_Click(object sender, EventArgs e) { frmChangePassword frm = new frmChangePassword(); frm.Show(); } } }
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; using 简单的三层.BLL; namespace 简单的三层.UI { public partial class frmChangePassword : Form { public frmChangePassword() { InitializeComponent(); } private void btn_ChangePassword_Click(object sender, EventArgs e) { // 采集数据 string old = textBox1.Text; string new1 = textBox2.Text; string new2 = textBox3.Text; // 调用业务逻辑层方法 T_SeatsBll bll = new T_SeatsBll(); ChangePasswordResult result = bll.ChangePassWord(GlobalHelper.auto_id,old,new1,new2); switch (result) { case ChangePasswordResult.DiffNewPassword: MessageBox.Show("两次输入的新密码不一致"); break; case ChangePasswordResult.ErrorOldPassword: MessageBox.Show("旧密码错误"); break; case ChangePasswordResult.Succeed: MessageBox.Show("修改密码成功"); break; case ChangePasswordResult.Faild: MessageBox.Show("修改密码错误"); break; default: break; } } } }
4、除了三层之外还有Model层,该层不在三层之内,一般它用于各层之间数据的传递
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace 简单的三层.Model { public class T_Seat { // 用来存储数据库表中的数据 public int CC_AutoId { get; set; } public string CC_LoginId { get; set; } public string CC_LoginPassword { get; set; } public string CC_UserName { get; set; } public int CC_ErrorTimes { get; set; } public DateTime? CC_LockDataTime { get; set; } public int? CC_Testint { get; set; } } }