当我单击按钮时,它显示一个值。然后我再次单击,它仍然相同,如何单击按钮,然后接下来显示一个新值?
try {
String bdUrl = jdbc:sqlserver://127.0.0.1:1433;databaseName=login;user=sa;password=123;"
Connection conn = DriverManager.getConnection(bdUrl);
String sql = "select cauhoi , caul,cau2,cau3,caudung from tracnghiem";
Statement statement = conn.createStatement();
Resultset rs = statement.excuteQuery(sql);
while (rs.next())
{
String cauhoil = rs.getString(1);
String dapana = rs.getString(2);
String dapanb = rs.getString(3);
String dapanc = rs.getString(4);
String dapand = rs.getString(5);
lbl.setText(""+cauhoil);
jrd1.setText(dapana);
jrd2.setText(dapanb);
jrd3.setText(dapanc);
jrd4.setText(dapand);
}}
catch (Exception e)
{
System.out.println(e);
}
它显示相同的值,因为您的SQL语句每次执行时都是相同的。因为您将不断更新循环中的Swing组件,所以您将始终在ResultSet中看到最后一个值。
相反,您需要: