实体类：
using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace 实体类_数据访问类.App_Code { public class Users { private int _code; /// <summary> /// code /// </summary> public int Code { get { return _code; } set { _code = value; } } private string _usename; /// <summary> /// 用户名 /// </summary> public string Usename { get { return _usename; } set { _usename = value; } } private string _password; /// <summary> /// 用户密码 /// </summary> public string Password { get { return _password; } set { _password = value; } } private string _nick; /// <summary> /// 昵称 /// </summary> public string Nick { get { return _nick; } set { _nick = value; } } private bool _sex; /// <summary> /// 性别 /// </summary> public bool Sex { get { return _sex; } set { _sex = value; } } private string _nation; /// <summary> /// 民族 /// </summary> public string Nation { get { return _nation; } set { _nation = value; } } private string _class; /// <summary> /// 班级 /// </summary> public string _class1 { get { return _class; } set { _class = value; } } private DateTime _birthday; /// <summary> /// 生日 /// </summary> public DateTime Birthday { get { return _birthday; } set { _birthday = value; } } } }
数据访问类：
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.SqlClient; namespace 实体类_数据访问类.App_Code { public class UserDate { SqlConnection conn = null; SqlCommand com = null; public UserDate() { conn = new SqlConnection("server=.;database=Data1128;user=sa;pwd=123"); com = conn.CreateCommand(); } /// <summary> /// 将数据添加到Users表中，添加成功返回true,失败返回false /// </summary> /// <param name="u">要添加到表中的Users对象</param> /// <returns>添加成功返回true,失败返回false</returns> public bool insert(Users u) { bool ok = false; int count = 0; com.CommandText = "insert into Users values(@usename,@password,@nick,@sex,@nation,@class,@birthday)"; com.Parameters.Clear(); com.Parameters.AddWithValue("@usename",u.Usename); com.Parameters.AddWithValue("@password", u.Password); com.Parameters.AddWithValue("@nick", u.Nick); com.Parameters.AddWithValue("@sex", u.Sex); com.Parameters.AddWithValue("@nation", u.Nation); com.Parameters.AddWithValue("@class", u._class1); com.Parameters.AddWithValue("@birthday", u.Birthday); try { conn.Open(); count=com.ExecuteNonQuery(); } catch { ok = false; } finally { conn.Close(); } if(count>0) { ok = true; } return ok; } /// <summary> /// 通过泛型集合对数据进行查询 /// </summary> /// <returns>返回一个集合</returns> public List<Users> Select() { List<Users> list= new List<Users>(); com.CommandText = "select *from Users"; conn.Open(); SqlDataReader dr = com.ExecuteReader(); if(dr.HasRows) { while(dr.Read()) { Users u = new Users(); u.Code = Convert.ToInt32(dr["code"]); u.Usename = dr["usename"].ToString(); u.Password = dr["password"].ToString(); u.Nick = dr["nick"].ToString(); u.Sex = Convert.ToBoolean(dr["sex"]); u.Nation = dr["nation"].ToString(); u._class1 = dr["class"].ToString(); u.Birthday = Convert.ToDateTime(dr["birthday"]); list.Add(u); } } conn.Close(); return list; } /// <summary> /// 根据usename进行查询 /// </summary> /// <param name="usename">要查询的usename对象</param> /// <returns>返回bool类型的值，返回true表示有usename这条数据</returns> public bool select(string usename) { bool has = false; com.CommandText = "select *from Users where usename=@usename"; com.Parameters.Clear(); com.Parameters.AddWithValue("@usename",usename); conn.Open(); SqlDataReader dr = com.ExecuteReader(); if(dr.HasRows) { has = true; } conn.Close(); return has; } //public void delete(string username) //{ // com.CommandText = "delete from Users where usename=@usename"; // com.Parameters.Clear(); // com.Parameters.AddWithValue("@usename", username); // conn.Open(); // com.ExecuteNonQuery(); // conn.Close(); //} /// <summary> /// 删除数据 /// </summary> /// <param name="username">要查询的usename对象</param> /// <returns>返回bool类型的值，返回true表示删除成功</returns> public bool delete(string username) { bool have = false; int cc = 0; com.CommandText = "delete from Users where usename=@usename"; com.Parameters.Clear(); com.Parameters.AddWithValue("@usename", username); try { conn.Open(); cc = com.ExecuteNonQuery(); } catch { have = false; } finally { conn.Close(); } if (cc > 0) { have = true; } return have; } } }
业务逻辑类：
using System; using System.Collections.Generic; using System.Linq; using System.Text; using 实体类_数据访问类.App_Code; namespace 实体类_数据访问类 { class Program { static void Main(string[] args) { //完整查询操作，创建泛型数组引用UsersDate的Select方法 List<Users> ulist = new UserDate().Select(); //遍历数组 foreach(Users uuu in ulist) { Console.WriteLine(uuu.Code+" "+uuu.Usename+" "+uuu.Password+" "+uuu.Nick+" "+uuu.Sex+" "+uuu.Nation+" "+uuu._class1+" "+uuu.Birthday); } //完整删除操作 Console.WriteLine("请输入要删除的用户名："); string uname = Console.ReadLine(); //select方法的返回值为true，说明有此用户 if (new UserDate().select(uname)) { Console.WriteLine("已查到此用户信息，是否要删除？(Y/N)");//用户操作 string yn = Console.ReadLine(); if (yn.ToUpper() == "Y") { //delete方法的返回值为true，删除成功 if (new UserDate().delete(uname)) Console.WriteLine("删除成功！"); //delete方法的返回值为false，删除失败 else Console.WriteLine("删除失败！"); } else { Console.WriteLine("取消删除！！"); } } //select方法的返回值为false，无此用户 else { Console.WriteLine("未查到此用户信息！！"); } //Console.WriteLine("请输入要删除的用户名："); //string uname = Console.ReadLine(); //if (new UserDate().select(uname)) //{ // Console.WriteLine("已查到此用户信息，是否要删除？(Y/N)"); // string yn = Console.ReadLine(); // if (yn.ToUpper() == "Y") // { // new UserDate().delete(uname); // Console.WriteLine("删除成功！"); // } // else // { // Console.WriteLine("取消删除！！"); // } //} //else //{ // Console.WriteLine("未查到此用户信息！！"); //} //添加用户操作 Users user = new Users(); Console.WriteLine("请输入用户名："); user.Usename = Console.ReadLine(); Console.WriteLine("请输入密码："); user.Password = Console.ReadLine(); Console.WriteLine("请输入昵称："); user.Nick = Console.ReadLine(); Console.WriteLine("请输入性别："); user.Sex = Convert.ToBoolean(Console.ReadLine()); Console.WriteLine("请输入民族："); user.Nation = Console.ReadLine(); Console.WriteLine("请输入班级："); user._class1 = Console.ReadLine(); Console.WriteLine("请输入生日："); user.Birthday = Convert.ToDateTime(Console.ReadLine()); UserDate ud = new UserDate(); bool isok= ud.insert(user);//数据访问类中insert方法的返回值 if (isok) Console.WriteLine("添加成功！"); else Console.WriteLine("添加失败！！"); Console.ReadLine(); } } }