public void Btn_Login_actionPerformed(ActionEvent e) {

      String password_text=PassWord_Text.getText();
      String username_text=UserName_Text.getText();
       if(username_text.equals("")|| password_text.equals(""))
       {
            JOptionPane.showMessageDialog(null,"用戶名或密碼不能為空！");
        }else{

          try{
          //建立數(shù)據(jù)庫連接對象
          Jdbcconn conn = new Jdbcconn();
          //連接數(shù)據(jù)庫
          conn.OpenConn("student","sa","yaya");         
          String strSQL="select * from student where Uno='"+username_text+"'";
          //得到記錄；
          try {
              ResultSet rs = conn.getResults(strSQL);
              rs.first();
              String PassWord = rs.getString("Upwd"); //得到數(shù)據(jù)庫中對應(yīng)用戶名的密碼
              if (PassWord.equals(password_text)) {
                  JOptionPane.showMessageDialog(null, "成功登陸！");
              } else {
      
                  JOptionPane.showMessageDialog(null, "密碼錯誤，請重輸！");
                  PassWord_Text.setText("");
              }
      
          } catch (Exception ex) {
              JOptionPane.showMessageDialog(null, "用戶名或密碼錯誤！");
              UserName_Text.setText("");
              PassWord_Text.setText("");
              System.out.print(ex.getMessage());
              
      
          }
            
          
          }catch(Exception ex)
          {
          System.out.print(ex.getMessage());
          }



           System.out.println("username_text:"+username_text);
           System.out.println("password_text:"+password_text);

        }
    }
}