• Ado.Net 数据库增删改查


    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Data.SqlClient;   //引用命名空间
    
    namespace 增删改查
    {
        class Program
        {
            static void Main(string[] args)
            {
           //增:insert into
    //1.连接数据库 SqlConnection con = new SqlConnection("server=.; database=ADO; user=sa; pwd=ray;"); //2.编写SQL语句 string sql = "insert into Student values('钱八',1,'1990-01-05','90','22050219900105061X','18853315510')"; //3.创建一个执行SQL语句的对象 using (SqlCommand cmd = new SqlCommand(sql, con)) { con.Open(); //4.打开连接 int z = cmd.ExecuteNonQuery(); //5.执行语句 Console.WriteLine("成功插入了{0}行数据 " + sql, z); con.Close(); //6.关闭连接 Console.ReadKey(); } } } }

                //删:delete
                SqlConnection con = new SqlConnection("server=.; database=ADO; user=sa; pwd=ray;");
                string sql = "delete from Student where Sname='钱八'";
                using (SqlCommand cmd = new SqlCommand(sql, con))
                {
                    con.Open();
                    int s = cmd1.ExecuteNonQuery();
                    Console.WriteLine("成功删除了{0}行数据
    " + sql, s);
                    con.Close();
                    Console.ReadKey();
                }

                //(3)改:update...set
                SqlConnection con = new SqlConnection("server=.; database=ADO; user=sa; pwd=ray;");
                string sql = "update Student set Sname='张小三',Sbirthday='2000-01-01',Sscore=100 where Scode=10001";
                using (SqlCommand cmd=new SqlCommand(sql,con))
                {
                    con.Open();
                    int g = cmd.ExecuteNonQuery();
                    Console.WriteLine("成功更改了{0}行数据
    "+sql,g);
                    con.Close();
                    Console.ReadKey();
                }

                //(4)查:select
    SqlConnection con = new SqlConnection("server=.; database=ADO; user=sa; pwd=ray;"); string sql = "select count(*) from Student"; using (SqlCommand cmd=new SqlCommand(sql,con)) { con.Open(); object c=cmd.ExecuteScalar(); Console.WriteLine("Student表中共有{0}条数据",c); con.Close(); Console.ReadKey(); }

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  • 原文地址:https://www.cnblogs.com/xiao55/p/5604817.html
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