// 1.连接字符串 string constr = "Data Source=ZHENDONG-PC;Initial Catalog=MyDatabaseOne;Integrated Security=True"; // 2.创建连接对象 using (SqlConnection con = new SqlConnection(constr)) { // 4.编写sql语句 string sql = "insert into TblPerson values('FFF',24,175,1)"; // 5.创建一个执行sql语句的对象(命令对象)SqlCommand using (SqlCommand cmd = new SqlCommand(sql, con)) { // 3.打开连接(连接对象最晚打开,最早关闭。节省资源) con.Open(); // 6.开始执行sql语句 int r = cmd.ExecuteNonQuery(); Console.WriteLine("成功插入了{0}行数据。", r); } } Console.ReadKey();
删除一条数据
// 1.连接字符串 string constr = "Data Source=zhendong-pc;Initial Catalog=MyDatabaseOne;Integrated Security=True"; // 2.连接对象 using (SqlConnection con = new SqlConnection(constr)) { // 3.sql语句 string sql = "delete from TblPerson where id = '37'"; // 4.创建SqlCommand对象 using (SqlCommand cmd = new SqlCommand(sql, con)) { // 5.打开连接 con.Open(); // 6.执行 int r = cmd.ExecuteNonQuery(); Console.WriteLine("成功删除了{0}条数据", r); } } Console.ReadKey();
更新一条数据
string constr = "Data Source=.;Initial Catalog=MyDatabaseOne;Integrated Security=true"; using (SqlConnection con = new SqlConnection(constr)) { string sql = "update Tblperson set age = 25, address = 'address2' where id = '2'"; using (SqlCommand cmd = new SqlCommand(sql, con)) { con.Open(); int r = cmd.ExecuteNonQuery(); Console.WriteLine("成功更新{0}条数据", r); } } Console.ReadKey();
查询表中的记录条数
string constr = "Data Source=.;Initial Catalog=MyDatabaseOne;Integrated Security=true"; using (SqlConnection con = new SqlConnection(constr)) { string sql = "select count(*) from TblPerson"; using (SqlCommand cmd = new SqlCommand(sql, con)) { con.Open(); // 聚合函数不会返回null,所以不用判断是否为null object count = (int)cmd.ExecuteScalar(); Console.WriteLine("TblPerson表中共有{0}条数据", count); } } Console.ReadKey();