如何防止我的jComboBox重置？

I have a ResultSet. This ResultSet is filling a JComboBox with data like this:

我有一个ResultSet。这个ResultSet正在用这样的数据填充JComboBox：

DatabaseHandler dh = new DatabaseHandler();

public ResultSet Klanten;

public BestellingenNieuwPanel() {
    initComponents();
    //Removes all items from KlantBox.
    KlantBox.removeAllItems();
    //Removes all from ProductBox.
    ProductBox.removeAllItems();
        try {
        Klanten = dh.getDataFromDB("select * from klanten");
        while (Klanten.next()) {
            String strKlanten = Klanten.getString("Achternaam");
            KlantBox.addItem(Klanten.getString(3));
        }

    } catch (Exception e) {
        System.out.println(e.getMessage());
    }

This workes just fine. But, whenever I try to loop through ResultSet Klanten again like this:

这工作得很好。但是，每当我尝试再次循环ResultSet Klanten时，就像这样：

private void KlantBoxActionPerformed(java.awt.event.ActionEvent evt) {  

    if(Klanten != null){
        String strSelected = KlantBox.getSelectedItem().toString();            
        try {
            while(Klanten.next()){
                String KlantVoornaam = Klanten.getString(1);
                String KlantAchternaam = Klanten.getString(2);
                String KlantWoonplaats = Klanten.getString(4);
                if(strSelected == KlantAchternaam){
                    txtKlantNaam.setText(KlantAchternaam);
                    txtKlantWoonplaats.setText(KlantWoonplaats);
                }
            }
        } catch (SQLException ex) {
        }

    }
}

My JComboBox Klanten only has it's last value. I've fiddled around with the Klanten.next() function and found that that function is the source of the problem.

我的JComboBox Klanten只有它的最后一个值。我已经摆弄了Klanten.next（）函数，发现该函数是问题的根源。

Are there any other ways to loop through a ResultSet? Or is there a way to loop through a ResultSet WITHOUT resetting my JComboBox?

有没有其他方法来循环ResultSet？或者有没有办法循环ResultSet而不重置我的JComboBox？

2 个解决方案

#1

Don't compare strings like this if(strSelected == KlantAchternaam){ use equals() instead.

如果（strSelected == KlantAchternaam）{use equals（），请不要比较这样的字符串。

But in fact after refreshing the combobox just call setSelectedItem(strSelected )

但事实上刷新组合框后只需调用setSelectedItem（strSelected）

#2

I think the error is with your comparison of string using == rather than with your use of Klanteen.next()

我认为错误是你用字符串比较==而不是你使用Klanteen.next（）

Try using the following code

尝试使用以下代码

if(strSelected.equals(KlantAchternaam)){
                txtKlantNaam.setText(KlantAchternaam);
                txtKlantWoonplaats.setText(KlantWoonplaats);
            }

or this one, if you want to ignore case

或者这个，如果你想忽略大小写

if(strSelected.equalsIgnoreCase(KlantAchternaam)){
                txtKlantNaam.setText(KlantAchternaam);
                txtKlantWoonplaats.setText(KlantWoonplaats);
            }

#1