2016年11月28日--ADO.Net 查、插、删、改 小练习

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;

namespace ConsoleApplication1
{
    class Program
    {
        /// <summary>
        /// 执行TSQL语句
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public int zhixing(string str)
        {
            conn.Open();
            try
            {
                SqlCommand cmd = conn.CreateCommand();
                cmd.CommandText = str;
                int i = cmd.ExecuteNonQuery();
            conn.Close();
                return i;
            }
            catch (Exception ex) { Console.WriteLine(ex.Message);
            conn.Close(); return 0; }
        }
        static SqlConnection conn = new SqlConnection("server=.;database=Data0928;user=sa;pwd=123");





        /// <summary>
        /// 判断数据输入是否有误
        /// </summary>
        /// <param name="id">1：密码 2：昵称 3：性别 4：生日 5：民族 6：班级</param>
        /// <returns></returns>
        public string panduan(int id)
        {
            switch (id)
            {
                case 1:
                    //密码
                    for (; ; )
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入密码：");
                        string napw = Console.ReadLine();
                        if (napw != "")
                            return napw;
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("该字段不能为空");
                        }
                    }
                case 2:
                    //昵称
                    for (; ; )
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入昵称：");
                        string napw = Console.ReadLine();
                        if (napw != "")
                            return napw;
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("该字段不能为空");
                        }
                    }
                case 3:
                    //性别
                    for (; ; )
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入性别：");
                        string sex = Console.ReadLine();
                        if (sex != "")
                        {
                            if (sex == "True" || sex == "true" || sex == "男" || sex == "1" || sex == "雄")
                                return "True";
                            else if (sex == "False" || sex == "false" || sex == "女" || sex == "0" || sex == "雌")
                                return "False";
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("性别输入有误");
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("该字段不能为空");
                        }
                    }
                case 4:
                    //生日
                    for (; ; )
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入生日：");
                        try   //尝试去做，如果有错，从错误的句直接跳转到catch
                        {
                            DateTime zhi = DateTime.Parse(Console.ReadLine());
                            return zhi.ToShortDateString();
                        }
                        catch  //只有错误的情况下
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("输入日期格式错误");
                        }
                    }
                case 5:
                    //民族
                    for (; ; )
                    {
                        selectNation("Nation");
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入民族：N");
                        string nation = "";
                        int i = Convert.ToInt32(Console.ReadLine());
                        if (i < 0)
                            i = Math.Abs(i);
                        if (i < 999)
                        {
                            nation = "N" + i.ToString("000");

                            if (boselect("Nation", "NationCode", nation) || boselect("Nation", "NationName", nation))
                            {
                                return nation;
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("没有此民族编号或名称");
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("请输入数字1~999之间");
                        }
                    }
                case 6:
                    //班级
                    for (; ; )
                    {
                        selectNation("Class");
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入班级：C");
                        string nation = "";
                        int i = Convert.ToInt32(Console.ReadLine());
                        if (i < 0)
                            i = Math.Abs(i);
                        if (i < 999)
                        {
                            nation = "C" + i.ToString("000");

                            if (boselect("Class", "ClassCode", nation) || boselect("Class", "ClassName", nation))
                            {
                                return nation;
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("没有此班级编号或名称");
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("请输入数字1~999之间");
                        }
                    }
                default: break;
            }
            return "";
        }






        /// <summary>
        /// 判断要执行的操作
        /// </summary>
        /// <param name="id">操作编号</param>
        public void caozuo(int id)
        {
            switch (id)
            {
                case 1:
                    //查询select
                    while (true)
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入要查看的表名：");
                        string tabname = Console.ReadLine();
                        if (tabname != "")
                        {
                            Console.Write("请输入条件列名：");
                            string cluame = Console.ReadLine();
                            if (tabname != "")
                            {
                                Console.Write("请输入条件：");
                                string UserName = Console.ReadLine();
                                if (tabname != "")
                                {
                                    if (select(tabname, cluame, UserName))
                                    {
                                        break;
                                    }
                                }
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("该字段不能为空");
                        }
                    }
                    break;
                case 2:
                    //插入
                    while (true)
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入要插入的用户名：");
                        string UserName = Console.ReadLine();
                        if (!boselect("Users", "UserName", UserName))
                        {
                            string pwd = panduan(1);
                            string nick = panduan(2);
                            string sex = panduan(3);
                            string bir = panduan(4);
                            string nation = panduan(5);
                            string cla = panduan(6);
                            if (zhixing("insert into Users values(‘" + UserName + "‘,‘" + pwd + "‘,‘" + nick + "‘,‘" + sex + "‘,‘" + bir + "‘,‘" + nation + "‘,‘" + cla + "‘)") > 0)
                            {
                                Console.WriteLine("成了"); break;
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("没成");
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("此用户名以存在请更改。");
                        }
                    }
                    break;
                case 3:
                    //删除
                    while (true)
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入要删除的用户名：");
                        string UserName = Console.ReadLine();
                        if (boselect("Users", "UserName", UserName))
                        {
                            if (zhixing("DELETE FROM Users WHERE UserName=‘" + UserName + "‘") > 0)
                            {
                                Console.WriteLine("成了"); break;
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("没成");
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("此用户名不存在请更改。");
                        }
                    }
                    break;
                case 4:
                    //修改
                    while (true)
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入要修改的用户名：");
                        string UserName = Console.ReadLine();
                        if (boselect("Users", "UserName", UserName))
                        {
                            string pwd = panduan(1);
                            string nick = panduan(2);
                            string sex = panduan(3);
                            string bir = panduan(4);
                            string nation = panduan(5);
                            string cla = panduan(6);
                            if (zhixing("update Users set PassWord = ‘" + pwd + "‘,NickName = ‘" + nick + "‘,Sex=‘" + sex + "‘,Birthday=‘" + bir + "‘,Nation=‘" + nation + "‘,Class=‘" + cla + "‘ where UserName = ‘" + UserName + "‘") > 0)
                            {
                                Console.WriteLine("成了"); break;
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("没成");
                            }
                        }
                        else
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("此用户名不存在请更改。");
                        }
                    }
                    break;
                default:
                    break;
            }
        }


        /// <summary>
        /// 查询语句
        /// </summary>
        /// <param name="tabname">要查询的表名</param>
        /// <param name="cluame">要查询的条件列</param>
        /// <param name="UserName">条件</param>
        /// <returns></returns>
        public bool select(string tabname, string cluame, string UserName)
        {
            try
            {
                SqlCommand cmd = conn.CreateCommand();
                Console.ForegroundColor = ConsoleColor.Blue;
                if (tabname == "Users" || tabname == "users")
                {
                    conn.Open();
                    cmd.CommandText = "SELECT ids,UserName,[PassWord],NickName,Sex,Birthday,NationName as Nation,ClassName AS Class FROM Users,Class,Nation WHERE Nation=NationCode AND Class=ClassCode AND " + cluame + "=‘" + UserName + "‘";

                    SqlDataReader dr = cmd.ExecuteReader();
                    Console.WriteLine("┌──────────────────────────────────┐");
                    Console.WriteLine("│　ID\t用户名\t密码\t昵称\t性别\t生日\t\t民族\t班级　│");
                    if (dr.HasRows)
                    {
                        while (dr.Read())
                        {
                            Console.WriteLine("│　{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{6}\t{7}　│", dr["ids"], dr["username"], dr["PassWord"], dr["NickName"], dr["Sex"], Convert.ToDateTime(dr["Birthday"]).ToShortDateString(), dr["Nation"], dr["class"]);
                        }
                        Console.WriteLine("└──────────────────────────────────┘");
                        conn.Close();
                        return true;
                    }
                    else
                    {
                        Console.WriteLine("│──────────────────────────────────│");
                        Console.WriteLine("│─────────────未查到任何数据──────────────│");
                        Console.WriteLine("│──────────────────────────────────│");
                        Console.WriteLine("└──────────────────────────────────┘");
                        conn.Close();
                        return false;
                    }
                }
                else
                {
                    cmd.CommandText = "SELECT * FROM " + tabname + " where " + cluame + "=‘" + UserName + "‘";
                    SqlDataReader dr = cmd.ExecuteReader();
                    Console.WriteLine("┌───────────┐");
                    Console.WriteLine("│\t编号\t名称\t│");
                    conn.Open();
                    if (dr.HasRows)
                    {
                        while (dr.Read())
                        {
                            Console.WriteLine("│\t{0}\t{1}\t│", dr[0], dr[1]);
                        }
                        Console.WriteLine("└───────────┘");
                        conn.Close();
                        return true;
                    }
                    else
                    {
                        Console.WriteLine("│───────────│");
                        Console.WriteLine("│──未查到任何数据──│");
                        Console.WriteLine("│───────────│");
                        Console.WriteLine("└───────────┘");
                        conn.Close();
                        return false;
                    }
                }
            }
            catch
            {
                Console.ForegroundColor = ConsoleColor.Red;
                Console.WriteLine("表名、列名、数据输入有误");
                return false;
            }
        }



        /// <summary>
        /// 判断UserName是否存在
        /// </summary>
        /// <param name="tabname">表名</param>
        /// <param name="UserName">用户名</param>
        /// <returns></returns>
        public bool boselect(string tabname, string cluame, string UserName)
        {
            conn.Open();
            SqlCommand cmd = conn.CreateCommand();
            cmd.CommandText = "SELECT * FROM " + tabname + " where "+cluame+"=‘" + UserName + "‘";
            SqlDataReader dr = cmd.ExecuteReader();
            if (dr.HasRows)
            {
                conn.Close();
                return true;
            }
            else
            {
                conn.Close();
                return false;
            }
        }





        /// <summary>
        /// 打印所有用户数据
        /// </summary>
        public void selectall()
        {
            SqlCommand cmd = conn.CreateCommand();
            Console.ForegroundColor = ConsoleColor.Blue;
            Console.WriteLine("┌──────────────────────────────────┐");
            Console.WriteLine("│　ID\t用户名\t密码\t昵称\t性别\t生日\t\t民族\t班级　│");
            conn.Open();
            cmd.CommandText = "SELECT ids,UserName,[PassWord],NickName,Sex,Birthday,NationName as Nation,ClassName AS Class FROM Users,Class,Nation WHERE Nation=NationCode AND Class=ClassCode";
            SqlDataReader dr = cmd.ExecuteReader();
            if (dr.HasRows)
            {
                while (dr.Read())
                {
                    Console.WriteLine("│　{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{6}\t{7}　│", dr["ids"], dr["username"], dr["PassWord"], dr["NickName"], dr["Sex"], Convert.ToDateTime(dr["Birthday"]).ToShortDateString(), dr["Nation"], dr["class"]);
                }
            }
            else
            {
                Console.WriteLine("│──────────────────────────────────│");
                Console.WriteLine("│─────────────未查到任何数据──────────────│");
                Console.WriteLine("│──────────────────────────────────│");
            }
            conn.Close();
            Console.WriteLine("└──────────────────────────────────┘");
        }





        /// <summary>
        /// 打印所有民族与代码
        /// </summary>
        public void selectNation(string tabname)
        {
            SqlCommand cmd = conn.CreateCommand();
            Console.ForegroundColor = ConsoleColor.Blue;
            Console.WriteLine("┌───────────┐");
            Console.WriteLine("│\t编号\t名称\t│");
            conn.Open();
            cmd.CommandText = "SELECT * FROM " + tabname;
            SqlDataReader dr = cmd.ExecuteReader();
            if (dr.HasRows)
            {
                while (dr.Read())
                {
                    Console.WriteLine("│\t{0}\t{1}\t│", dr[0], dr[1]);
                }
            }
            else
            {
                Console.WriteLine("│───────────│");
                Console.WriteLine("│──未查到任何数据──│");
                Console.WriteLine("│───────────│");
            }
            conn.Close();
            Console.WriteLine("└───────────┘");


        }



        static void Main(string[] args)
        {
            Program pr = new Program();
            SqlCommand cmd = conn.CreateCommand();

            //打印所有人的数据
            pr.selectall();
            while (true)
            {
                Console.ForegroundColor = ConsoleColor.Yellow;
                Console.WriteLine("1.查询");
                Console.WriteLine("2.插入");
                Console.WriteLine("3.删除");
                Console.WriteLine("4.修改");
                Console.Write("请选择要执行的操作：");
                try
                {
                    int biao = Convert.ToInt32(Console.ReadLine());
                    if (biao > 0 && biao < 5)
                    {
                        pr.caozuo(biao);
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.Write("请输入任意键继续_");
                        Console.ReadKey();
                        Console.Clear();
                        pr.selectall();
                    }
                    else
                    {
                        Console.Clear();
                        pr.selectall();
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.WriteLine("请输入1~4进行选择");
                    }
                }
                catch
                {
                    Console.Clear();
                    pr.selectall();
                    Console.WriteLine("请输入数字1~4进行选择");
                }
            }
        }
    }
}