winform中简单登录界面设计

一、winform中简单登录界面设计，经常会用的到吆！

1.首先拖两个label控件，label1、label2、两个TextBox、两个Button按钮，分别命名为：tbUser.Text、tbPwd.Text，btnLog(登录)、btnCancel (取消)，操作代码如下： 

private void btnLog_Click(object sender, EventArgs e)
        {
            string user = tbUser.Text.ToString();
            string pwd = tbPwd.Text.ToString();
            if (user == "" || pwd == "")
            {
                MessageBox.Show("请输入用户名和密码！");
            }
            else
            {

                 //定义sql查询语句、数据源连接
                string sql = "select SYSUSER_UN,SYSUSER_PWD from SYSUSER where SYSUSER_UN='" + tbUser.Text + "'and  SYSUSER_PWD='" + tbPwd.Text + "'";
                SqlConnection conn = new SqlConnection("Data Source=119.188.4.70,10070;Initial Catalog=fsjx_db;Persist Security Info=True;User ID=sa;Password=SQL_fsjx_Svr@sa133");
                conn.Open();
                SqlCommand cmd = new SqlCommand(sql, conn);
                SqlDataReader dr = cmd.ExecuteReader();
                if (dr.Read())
                {
                    MessageBox.Show("登录成功！");
                }
                else
                {
                    MessageBox.Show("用户名或密码不正确，请重新输入！");

                }
                dr.Close();
                conn.Close();
           }

    }

 private void btnCancel_Click(object sender, EventArgs e)
        {
            this.DialogResult = DialogResult.Cancel;
        }