ACCP S1 C#第十七章

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data.SqlClient; namespace no17 { class Program { static void Main(string[] args) { dbhandle d = new dbhandle(); d.login(); } } }

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data.SqlClient; namespace no17 { class usermanager { public void showmenu() { bool b=true; do { dbhandle d = new dbhandle(); Console.WriteLine("=======欢迎登陆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.添加用户新纪录"); 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("========================================"); string i = Console.ReadLine(); switch (i) { case "1": d.getuserlist(); break; case "2": d.updateonlineday(); break; case "3": d.insertuserinfo(); break; case "4": d.updatelevel(); break; case "5": d.deleteuserinfo(); break; case "0": Console.WriteLine("是否退出(y/n)"); string answer = Console.ReadLine(); if (answer=="y") { b = false; } break; } } while (b); } } }

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data.SqlClient; namespace no17 { class dbhandle { usermanager u = new usermanager(); public void login() { string s; string ss; int j; for(int i=0;i<3;){ s = "Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; SqlConnection c = new SqlConnection(s); Console.WriteLine("请输入用户名:"); string name = Console.ReadLine(); Console.WriteLine("请输入密码:"); string pwd =Console.ReadLine(); c.Open(); ss = "select count(*) from admin where loginid='"+name+"' and loginpwd='"+pwd+"'"; SqlCommand d = new SqlCommand(ss, c); j = (int)d.ExecuteScalar(); if (j != 0) { Console.WriteLine("登陆成功"); c.Close(); u.showmenu(); break; } else { i++; if (i == 3) { Console.WriteLine("三次失败,退出"); break; } Console.WriteLine("登陆失败"); } c.Close(); } Console.ReadLine(); } public void getuserlist() { string s = "Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; SqlConnection c = new SqlConnection(s); c.Open(); StringBuilder sb = new StringBuilder(); sb.Append("select * from userinfo u inner join level l on l.levelid=u.levelid"); SqlCommand d = new SqlCommand(sb.ToString(), c); SqlDataReader r = d.ExecuteReader(); Console.WriteLine("ID 用户名 用户密码 等级 电子邮箱 在线天数"); while (r.Read()) { Console.WriteLine(r["userid"] + " " + r["username"] + " " + r["userpwd"] + " " + r["levelname"] + " " + r["email"] + " " + r["onlineday"]); } r.Close(); c.Close(); Console.ReadLine(); } public void updateonlineday(){ string s = "Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; SqlConnection c = new SqlConnection(s); c.Open(); Console.WriteLine("请输入用户ID:"); string name=Console.ReadLine(); Console.WriteLine("请输入新的天数:"); float day =float.Parse(Console.ReadLine()); StringBuilder sb = new StringBuilder(); sb.Append("update userinfo set onlineday='"+day+"' where userid='"+name+"'"); SqlCommand d = new SqlCommand(sb.ToString(), c); int i = d.ExecuteNonQuery(); if (i != 0) { Console.WriteLine("修改成功!"); } else { Console.WriteLine("修改失败!"); } c.Close(); Console.ReadLine(); } public void insertuserinfo() { string s = "Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; SqlConnection c = new SqlConnection(s); c.Open(); Console.WriteLine("请输入用户昵称:"); string name = Console.ReadLine(); Console.WriteLine("请输入密码:"); string pwd = Console.ReadLine(); Console.WriteLine("请输入邮箱地址:"); string em = Console.ReadLine(); StringBuilder sb = new StringBuilder(); sb.Append("insert into userinfo(username,userpwd,email) values('" + name + "','" + pwd + "','" + em + "')"); SqlCommand d = new SqlCommand(sb.ToString(), c); int i = d.ExecuteNonQuery(); if (i != 0) { string a = "select userid from userinfo where username='"+name+"'"; SqlCommand m = new SqlCommand(a,c); int j = (int)m.ExecuteScalar(); Console.WriteLine("插入成功!用户编号是:"+j); } else { Console.WriteLine("插入失败!"); } c.Close(); Console.ReadLine(); } public void updatelevel() { string s = "Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; SqlConnection c = new SqlConnection(s); c.Open(); StringBuilder sb = new StringBuilder(); sb.Append("update userinfo set levelid=1 where onlineday>0 and onlineday<5"); sb.Append("update userinfo set levelid=2 where onlineday>4 and onlineday<32"); sb.Append("update userinfo set levelid=3 where onlineday>31 and onlineday<320"); sb.Append("update userinfo set levelid=4 where onlineday>319"); SqlCommand d = new SqlCommand(sb.ToString(), c); int i = d.ExecuteNonQuery(); if (i != 0) { Console.WriteLine("本次共更新用户记录数:"+i); Console.WriteLine("更新成功!"); } else { Console.WriteLine("修改失败!"); } c.Close(); Console.ReadLine(); } public void deleteuserinfo() { string s = "Data Source=.;Initial Catalog=QQDB;Integrated Security=True"; SqlConnection c = new SqlConnection(s); c.Open(); Console.WriteLine("请输入用户ID:"); string name = Console.ReadLine(); StringBuilder sb = new StringBuilder(); sb.Append("select * from userinfo where userid='" + name + "'"); SqlCommand d = new SqlCommand(sb.ToString(), c); int i = d.ExecuteNonQuery(); if (i != 0) { SqlDataReader r = d.ExecuteReader(); r.Read(); Console.WriteLine("将要删除的用户信息是:"); Console.WriteLine(r["userid"] + " " + r["username"] + " " + r["levelid"] + " " + r["email"] + " " + r["onlineday"]); Console.WriteLine("要删除该用户记录吗?(y/n)"); string answer = Console.ReadLine(); if (answer == "y") { StringBuilder sb1 = new StringBuilder(); sb1.Append("delete from userinfo where userid='" + name + "'"); SqlCommand d1 = new SqlCommand(sb1.ToString(), c); Console.WriteLine("删除成功!"); } } else { Console.WriteLine("删除失败!"); } c.Close(); Console.ReadLine(); } } }