1、建立连接数据库
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Data;
6 using System.Data.SqlClient;
7
8
9 namespace 连接数据库
10 {
11 class Program
12 {
13 static void Main(string[] args)
14 { //要连接数据库就要一个连接字符串,连接数据库的实例名,数据库名,用户名和密码
15 //string sqlConn = @"server=.\sqlexpress;database=MyDataBase;uid=sa;pwd=123";
16 //string sqlConn = @"server=.;database=MyDataBase;Integrated security=true";//Windonws集成登录
17
18 //打开连接
19 string sqlConn = @"server=.\sqlexpress;database=MyDataBase;uid=sa;pwd=123";
20 SqlConnection conn = new SqlConnection(sqlConn);
21
22 conn.Open();
23 Console.WriteLine("OKS");
24 string sts = @"create table UseLogin (id int identity(1,1) primary key,name nvarchar(10),pwd nvarchar(16) check(len(pwd) between 6 and 16))";
25 SqlCommand cmd = new SqlCommand(sts, conn);
26 using (cmd)
27 {
28 //cmd.ExecuteNonQuery();
29 }
30 using (conn)
31 {
32 SqlCommand cmd1 = new SqlCommand("insert into UseLogin (name,pwd) values('找2','1231234');",conn);
33 using (cmd)
34 {
35 int res = cmd1.ExecuteNonQuery();
36 Console.WriteLine("{0}行受影响",res);
37 }
38 }
39 Console.ReadKey();
40 }
41 }
42 }
2、查询
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
namespace 查找
{
class Program
{
static void Main(string[] args)
{
string sqlConn = @"server=.;database=MyDataBase;Integrated security=true";
string sql = @"select count(*) from uselogin where name='张三'";
using (SqlConnection conn = new SqlConnection(sqlConn))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
if (conn.State == System.Data.ConnectionState.Closed)
{
conn.Open();
}
int res = Convert.ToInt32(cmd.ExecuteScalar());
Console.WriteLine("找到{0}个", res);
}
}
Console.ReadKey();
}
}