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  • ADO.net增删改的使用

    添加数据

    --------------------------------------------------

    //让用户输入要添加的内容
    Console.WriteLine("请输入要添加的代号:");
    string code = Console.ReadLine();

    Console.WriteLine("请输入姓名:");
    string name = Console.ReadLine();

    Console.WriteLine("请输入性别:");
    bool sex = Console.ReadLine()=="男"?true:false;

    Console.WriteLine("请输入民族:");
    string nation = Console.ReadLine();

    Console.WriteLine("请输入生日:");
    string birthday = Console.ReadLine();

    string nationcode = "n001";

    //将民族名称转为名族代号
    SqlConnection conn = new SqlConnection("server=.;database=mydb;user=sa;pwd=123");
    SqlCommand cmd = conn.CreateCommand();
    cmd.CommandText = "select Code from Nation where Name = '"+nation+"'";
    conn.Open();
    SqlDataReader dr = cmd.ExecuteReader();
    if (dr.HasRows)
    {
    dr.Read();
    nationcode = dr[0].ToString();
    }
    conn.Close();

    //往Info表添加数据
    cmd.CommandText = "insert into Info values('"+code+"','"+name+"','"+sex+"','"+nationcode+"','"+birthday+"')";
    conn.Open();
    cmd.ExecuteNonQuery();
    conn.Close();
    Console.WriteLine("添加成功!");

    Console.ReadLine();

    ------------------------------------------------------

    删除数据

    ----------------------------------------------------------------

    //用户输入要删除的数据主键值
    Console.WriteLine("请输入要删除的代号:");
    string code = Console.ReadLine();

    //判断该数据存不存在
    SqlConnection conn = new SqlConnection("server=.;database=mydb;user=sa;pwd=123");
    SqlCommand cmd = conn.CreateCommand();
    cmd.CommandText = "select * from Info where Code='"+code+"'";
    conn.Open();
    SqlDataReader dr = cmd.ExecuteReader();

    if (dr.HasRows)
    {
    //说明该数据存在
    Console.WriteLine("查到该数据,是否要执行删除操作,如果要删除请输入:1");
    int sc = Convert.ToInt32(Console.ReadLine());

    if (sc == 1)
    {
    //删除
    dr.Close(); //关闭读取器

    cmd.CommandText = "delete from Info where Code='"+code+"'";
    cmd.ExecuteNonQuery();
    Console.WriteLine("删除成功!");

    }
    else
    {
    //不删除
    dr.Read();

    string sex = Convert.ToBoolean(dr[2])?"男":"女";
    string nation = MinZu(dr[3].ToString());

    string str = "代号:"+dr[0]+" 姓名:"+dr[1]+" 性别:"+sex+" 民族:"+nation+" 生日:"+dr[4];

    Console.WriteLine(str);


    }
    }
    else
    {
    //数据不存在
    Console.WriteLine("输入的代号错误!");
    }

    conn.Close();
    Console.ReadLine();
    }


    static string MinZu(string code)
    {
    string name="";
    SqlConnection conn = new SqlConnection("server=.;database=mydb;user=sa;pwd=123");
    SqlCommand cmd = conn.CreateCommand();
    cmd.CommandText = "select Name from Nation where Code = '" + code + "'";
    conn.Open();
    SqlDataReader dr = cmd.ExecuteReader();
    if (dr.HasRows)
    {
    dr.Read();
    name = dr[0].ToString();
    }
    conn.Close();

    return name;

    ----------------------------------------------------------------

    修改数据

    将cmd.commandtext语句改为需要update语句即可

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  • 原文地址:https://www.cnblogs.com/dreamer666/p/5794311.html
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