ado.net增删改查练习

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient; namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
//创建数据库连接对象,并编写连接字符串,注意连接字符串不要写错
SqlConnection conn = new SqlConnection("server=.;database=Data0928;user=sa;pwd=123");
//创建数据库操作对象,创建过程是与刚创建的连接对象匹配起来
SqlCommand cmd = conn.CreateCommand();
for (; ; )
{
Console.Write("请输入你想要的操作序号(1、删除 2、添加 3、更改 4、查看)");
try
{ int code = int.Parse(Console.ReadLine());
if (code == )
{
//删除
Console.Write("请输入想要删除的用户名:");
string user = Console.ReadLine();
//编写操作语句 TSQL语句
cmd.CommandText = "select ids,UserName,PassWord,NickName,Sex,Birthday,(select NationName from Nation where NationCode=Users.Nation) as 'Nation' ,ClassName as 'Class' from Users join Class on Class.ClassCode=Users.Class where UserName='" + user + "'";
//数据库连接打开,准备执行操作
conn.Open();
SqlDataReader dr = cmd.ExecuteReader();//使用SqlDataReader类接受查询的数据
if (dr.HasRows)//判断dr里是否有数据 返回布尔类型
{
while (dr.Read())//循环每一行 当超出时返回false
{
Console.WriteLine(dr["ids"] + "\t" + dr["UserName"] + "\t" + dr["PassWord"] + "\t" + dr["NickName"] + "\t" + (Convert.ToBoolean(dr["Sex"]) ? "男" : "女") + "\t" + Convert.ToDateTime(dr["Birthday"]).ToString("yyyy年MM月dd日") + "\t" + dr["Nation"] + "\t" + dr["Class"]);
}
//关闭数据库连接
conn.Close();
Console.Write("是否确定删除此条数据?(Y/N)");
string yn = Console.ReadLine();
if (yn == "y")
{
cmd.CommandText = "delete from Users where UserName='" + user + "'";
conn.Open();
int i = cmd.ExecuteNonQuery();//执行操作,并记录受影响的行数
if (i > )
Console.WriteLine("删除成功。");
else
{
Console.WriteLine("删除失败");
}
conn.Close();
}
else if (yn == "n")
{
Console.WriteLine("取消删除。");
}
else
{
Console.WriteLine("输入有误!");
}
}
else
{
Console.WriteLine("查无此条数据!");
}
conn.Close();
}
else if (code == )
{
//添加
Console.Write("请输入想要添加的用户名:");
string uname = Console.ReadLine();
cmd.CommandText = "select * from Users";
conn.Open();
SqlDataReader dr = cmd.ExecuteReader();
int biao = ;
//查询用户名是否重复
if (dr.HasRows)
{
while (dr.Read())
{
if (dr["UserName"].ToString() == uname)
{
biao++;
break;
}
}
}
conn.Close();
if (biao == )//用户名无重复
{
string pwd;
for (; ; )
{
Console.Write("请输入密码(6到18位):");
string pwd1 = Console.ReadLine();
if (pwd1.Length >= && pwd1.Length <= )
{
pwd = pwd1;
break;
}
else
{
Console.WriteLine("密码长度不正确,请重新输入!");
continue;
}
}
Console.Write("请输入昵称:");
string nick = Console.ReadLine();
string sex;
for (; ; )
{
Console.Write("请输入性别(请输入男女或者0、1):");
string sex1 = Console.ReadLine();
if(sex1==""||sex1=="")
{
sex = sex1;
break;
}
else if (sex1 == "男" || sex1 == "女")
{
if (sex1 == "男")
{
sex = "";
break;
}
else
{
sex = "";
break;
}
}
else
{
Console.WriteLine("性别输入有误,请重新输入!");
continue;
}
}
string bir;
for (; ; )
{
Console.Write("请输入生日:");
try
{
DateTime dt = DateTime.Parse(Console.ReadLine());
bir = dt.ToString();
break;
}
catch
{
Console.WriteLine("生日日期输入有误,请重新输入!");
continue;
}
}
string nation;
for (; ; )
{
Console.Write("请输入民族:");
string nation1 = Console.ReadLine();
if(nation1=="汉族"||nation1=="汉")
{
nation = "N001";
break;
}
else if (nation1 == "满族" || nation1 == "满")
{
nation = "N002";
break;
}
else if (nation1 == "藏族" || nation1 == "藏")
{
nation = "N003";
break;
}
else if (nation1 == "彝族" || nation1 == "彝")
{
nation = "N004";
break;
}
else
{
Console.WriteLine("输入民族有误,请重新输入!");
continue;
}
}
string cla;
for (; ; )
{
Console.Write("请输入班级:");
string cla1 = Console.ReadLine();
if(cla1=="一班"||cla1=="一")
{
cla = "C001";
break;
}
else if (cla1 == "二班" || cla1 == "二")
{
cla = "C002";
break;
}
else if (cla1 == "三班" || cla1 == "三")
{
cla = "C003";
break;
}
else if (cla1 == "四班" || cla1 == "四")
{
cla = "C004";
break;
}
else
{
Console.WriteLine("输入班级有误,请重新输入!");
continue;
}
}
cmd.CommandText = "insert into Users values('" + uname + "','" + pwd + "','" + nick + "','" + sex + "','" + bir + "','" + nation + "','" + cla + "')";
conn.Open();
int s = cmd.ExecuteNonQuery();
if (s > )
{
Console.WriteLine("添加成功!");
}
else
{
Console.WriteLine("添加失败!");
}
conn.Close();
}
else//用户名重复
{
Console.WriteLine("该用户名已存在!");
}
}
else if(code==)
{
//更改
Console.Write("请输入想要更改的用户名:");
string user = Console.ReadLine();
cmd.CommandText = "select ids,UserName,PassWord,NickName,Sex,Birthday,(select NationName from Nation where NationCode=Users.Nation) as 'Nation' ,ClassName as 'Class' from Users join Class on Class.ClassCode=Users.Class where UserName='" + user + "'";
conn.Open();
SqlDataReader dr = cmd.ExecuteReader();
if (dr.HasRows)
{
while (dr.Read())
{
Console.WriteLine(dr["ids"] + "\t" + dr["UserName"] + "\t" + dr["PassWord"] + "\t" + dr["NickName"] + "\t" + (Convert.ToBoolean(dr["Sex"]) ? "男" : "女") + "\t" + Convert.ToDateTime(dr["Birthday"]).ToString("yyyy年MM月dd日") + "\t" + dr["Nation"] + "\t" + dr["Class"]);
}
conn.Close();
Console.Write("是否更改此条数据?(Y/N)");
string yn = Console.ReadLine();
if (yn == "y")
{
string pwd;
for (; ; )
{
Console.Write("请输入密码(6到18位):");
string pwd1 = Console.ReadLine();
if (pwd1.Length >= && pwd1.Length <= )
{
pwd = pwd1;
break;
}
else
{
Console.WriteLine("密码长度不正确,请重新输入!");
continue;
}
}
Console.Write("请输入昵称:");
string nick = Console.ReadLine();
string sex;
for (; ; )
{
Console.Write("请输入性别(请输入男女或者0、1):");
string sex1 = Console.ReadLine();
if (sex1 == "" || sex1 == "")
{
sex = sex1;
break;
}
else if (sex1 == "男" || sex1 == "女")
{
if (sex1 == "男")
{
sex = "";
break;
}
else
{
sex = "";
break;
}
}
else
{
Console.WriteLine("性别输入有误,请重新输入!");
continue;
}
}
string bir;
for (; ; )
{
Console.Write("请输入生日:");
try
{
DateTime dt = DateTime.Parse(Console.ReadLine());
bir = dt.ToString();
break;
}
catch
{
Console.WriteLine("生日日期输入有误,请重新输入!");
continue;
}
}
string nation;
for (; ; )
{
Console.Write("请输入民族:");
string nation1 = Console.ReadLine();
if (nation1 == "汉族" || nation1 == "汉")
{
nation = "N001";
break;
}
else if (nation1 == "满族" || nation1 == "满")
{
nation = "N002";
break;
}
else if (nation1 == "藏族" || nation1 == "藏")
{
nation = "N003";
break;
}
else if (nation1 == "彝族" || nation1 == "彝")
{
nation = "N004";
break;
}
else
{
Console.WriteLine("输入民族有误,请重新输入!");
continue;
}
}
string cla;
for (; ; )
{
Console.Write("请输入班级:");
string cla1 = Console.ReadLine();
if (cla1 == "一班" || cla1 == "一")
{
cla = "C001";
break;
}
else if (cla1 == "二班" || cla1 == "二")
{
cla = "C002";
break;
}
else if (cla1 == "三班" || cla1 == "三")
{
cla = "C003";
break;
}
else if (cla1 == "四班" || cla1 == "四")
{
cla = "C004";
break;
}
else
{
Console.WriteLine("输入班级有误,请重新输入!");
continue;
}
}
cmd.CommandText = "update User set Password='"+pwd+"',NickName='"+nick+"',Sex="+sex+",Birthday='"+bir+"',Nation='"+nation+"',Class='"+cla+"' where UserName='" + user + "'";
conn.Open();
int i = cmd.ExecuteNonQuery();//执行操作,并记录受影响的行数
if (i > )
Console.WriteLine("更改成功。");
else
{
Console.WriteLine("更改失败");
}
conn.Close();
}
else if (yn == "n")
{
Console.WriteLine("取消更改。");
}
else
{
Console.WriteLine("输入有误!");
}
}
else
{
Console.WriteLine("查无此条数据!");
}
conn.Close();
}
else if(code==)
{
//查看
Console.Write("请输入想要查看的用户名(输入*代表查看全部):");
string user = Console.ReadLine();
if (user != "*")
{
cmd.CommandText = "select ids,UserName,PassWord,NickName,Sex,Birthday,(select NationName from Nation where NationCode=Users.Nation) as 'Nation' ,ClassName as 'Class' from Users join Class on Class.ClassCode=Users.Class where UserName='" + user + "'";
}
else
{
cmd.CommandText = "select ids,UserName,PassWord,NickName,Sex,Birthday,(select NationName from Nation where NationCode=Users.Nation) as 'Nation' ,ClassName as 'Class' from Users join Class on Class.ClassCode=Users.Class";
}
conn.Open();
SqlDataReader dr = cmd.ExecuteReader();
if (dr.HasRows)
{
while (dr.Read())
{
Console.WriteLine(dr["ids"] + "\t" + dr["UserName"] + "\t" + dr["PassWord"] + "\t" + dr["NickName"] + "\t" + (Convert.ToBoolean(dr["Sex"]) ? "男" : "女") + "\t" + Convert.ToDateTime(dr["Birthday"]).ToString("yyyy年MM月dd日") + "\t" + dr["Nation"] + "\t" + dr["Class"]);
}
conn.Close();
}
else
{
Console.WriteLine("查无此条数据!");
}
conn.Close();
}
else
{
Console.WriteLine("无此操作序号有误,请重新输入!");
continue;
}
}
catch
{
Console.WriteLine("输入有误,请重新输入!");
continue;
}
}
}
}
}

ado.net增删改查练习

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