Chapter 1. Ado.Net 数据库增删改查

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\n" + 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\n" + 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\n"+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();
            }

 

Chapter 1. Ado.Net 数据库增删改查

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