1.启动服务:sql server 配置
2.windows验证进入sql server-安全-sa-改密码;
3.新建数据库booksystem;
4.public partial class Form1 : Form
{
SqlConnection conn;
public Form1()
{
InitializeComponent();
}
private void btnLogin_Click(object sender, EventArgs e)
{
try
{
conn.Open();
MessageBox.Show(conn.State.ToString());
}
catch (Exception ex)
{
//友好提示
MessageBox.Show(ex.Message);
//throw ex;
}
finally {
conn.Close();
MessageBox.Show(conn.State.ToString());
}
}
private void Form1_Load(object sender, EventArgs e)
{
conn = new SqlConnection("server=.;database=booksystem;uid=sa;pwd=sa");
}
}
5.sql
//String sqlStr = "select * from admin where admName='lyc' and admPwd='123'";
//Trim()去掉两边的空格
String sqlStr = @"select * from admin
where admName='" + this.txtName.Text.Trim() + "' and admPwd='" + this.txtPwd.Text.Trim() + "'";
cmd = new SqlCommand(sqlStr, conn);
conn.Open();
//object obj=cmd.ExecuteScalar();
try
{
//
Int32 count = (Int32)cmd.ExecuteScalar();
//int count = (int)cmd.ExecuteScalar();
MessageBox.Show("正确");
}
catch (Exception ex)
{
MessageBox.Show("用户名密码不正确");
//throw ex;
}
finally {
conn.Close();
}