winform —— 连接数据库SQL Server 2008

using System.Data.SqlClient;命名空间
sqlconnection:数据连接类
sqlcommand:数据库操作类
sqldatareader:读取

 

 

  1 using System;

  2 using System.Collections.Generic;

  3 using System.ComponentModel;

  4 using System.Data;

  5 using System.Data.SqlClient;

  6 using System.Drawing;

  7 using System.Linq;

  8 using System.Text;

  9 using System.Windows.Forms;

 10 

 11 namespace WindowsFormsApplication7

 12 {

 13     public partial class Form1 : Form

 14     {

 15         public Form1()

 16         {

 17             InitializeComponent();

 18         }

 19 

 20         private void button1_Click(object sender, EventArgs e)

 21         {

 22             string username = textBox1.Text;

 23             string upass = textBox2.Text;

 24 

 25             //第一步：连接到数据库

 26             SqlConnection conn = new SqlConnection("server=.;database=data1220;user=sa;pwd=");

 27             conn.Open();

 28             //第二步：写执行语句

 29             SqlCommand cmd = conn.CreateCommand();//通过conn创建sqlcommand对象

 30             cmd.CommandText = "select *from users where uname='"+username+"' and upass='"+upass+"'";

 31             SqlDataReader dr = cmd.ExecuteReader();//执行查询，返回sqldatareader对象

 32             if (dr.Read())

 33             {

 34                 MessageBox.Show("登陆成功！");

 35             }

 36             else

 37             {

 38                 MessageBox.Show("登陆失败！");

 39             }

 40 

 41             conn.Close();

 42         }

 43 

 44         private void button2_Click(object sender, EventArgs e)

 45         {

 46             //添加数据到数据库

 47             string username = textBox1.Text;

 48             string upass = textBox2.Text;

 49 

 50             //第一步：连接到数据库

 51             SqlConnection conn = new SqlConnection("server=.;database=data1220;user=sa;pwd=");

 52             conn.Open();

 53             SqlCommand cmd = conn.CreateCommand();

 54             cmd.CommandText = "insert into users values('"+username+"','"+upass+"')";

 55             int count=　cmd.ExecuteNonQuery();//增删改

 56             if (count > 0)

 57             {

 58                 MessageBox.Show("添加成功！");

 59             }

 60             else

 61             {

 62                 MessageBox.Show("添加失败！");

 63             }

 64             conn.Close();

 65         }

 66 

 67         private void button3_Click(object sender, EventArgs e)

 68         {

 69             string code = textBox3.Text;

 70             string uname = textBox1.Text;

 71             string upass = textBox2.Text;

 72             //第一步：连接到数据库

 73             SqlConnection conn = new SqlConnection("server=.;database=data1220;user=sa;pwd=");

 74             conn.Open();

 75             SqlCommand cmd = conn.CreateCommand();

 76             cmd.CommandText = "update users set uname='"+uname+"',upass='"+upass+"' where code="+code;

 77             int count=cmd.ExecuteNonQuery();

 78             if (count > 0)

 79             {

 80                 MessageBox.Show("修改成功！");

 81             }

 82             else

 83             {

 84                 MessageBox.Show("修改失败！");

 85             }

 86             conn.Close();

 87         }

 88 

 89         private void button4_Click(object sender, EventArgs e)

 90         {

 91             string code = textBox3.Text;

 92             SqlConnection conn = new SqlConnection("server=.;database=data1220;user=sa;pwd=");

 93             conn.Open();

 94             SqlCommand cmd = conn.CreateCommand();

 95             cmd.CommandText = "delete from users where code="+code;

 96             cmd.ExecuteNonQuery();

 97             conn.Close();

 98         }

 99 

100         private void Form1_Load(object sender, EventArgs e)

101         {

102 

103         }

104     }

105 }

View Code