java - 如何从 JOptionPane 中的字符串数组中选择索引值

Question

我创建了一个 JOptionPane 作为选择方法。我想要字符串数组的选择 1,2 或 3 的 int 值，这样我就可以将它用作计数器。如何获取数组的索引并将其设置为等于我的 int 变量loanChoice？

public class SelectLoanChoices {
    int loanChoice = 0;
    String[] choices = {"7 years at 5.35%", "15 years at 5.5%",
            "30 years at 5.75%"};
        String input = (String) javax.swing.JOptionPane.showInputDialog(null, "Select a Loan"
                ,"Mortgage Options",JOptionPane.QUESTION_MESSAGE, null,
                choices,
                choices[0]
                **loanChoice =**);
}

Answer 1

如果您希望返回选项的索引，可以使用JOptionPane.showOptionDialog()。否则，您将必须迭代选项数组才能根据用户选择查找索引。

例如:

public class SelectLoanChoices {
 public static void main(final String[] args) {
  final String[] choices = { "7 years at 5.35%", "15 years at 5.5%", "30 years at 5.75%" };
  final Object choice = JOptionPane.showInputDialog(null, "Select a Loan", "Mortgage Options",
    JOptionPane.QUESTION_MESSAGE, null, choices, choices[0]);
  System.out.println(getChoiceIndex(choice, choices));

 }

 public static int getChoiceIndex(final Object choice, final Object[] choices) {
  if (choice != null) {
   for (int i = 0; i < choices.length; i++) {
    if (choice.equals(choices[i])) {
     return i;
    }
   }
  }
  return -1;
 }
}