Question

我遇到的问题是这段代码：

       String birthString = JOptionPane.showInputDialog(
           null, "Enter birth year: ", "How long have you been alive?",
           JOptionPane.QUESTION_MESSAGE);      
   Pattern p = Pattern.compile("[A-Z,a-a,&%$#@!()*^]");
   Matcher m = p.matcher(birthString);
   if (m.find()){
       JOptionPane.showMessageDialog(null, 
             "That doesn't look like numbers to me... Try again.",
             "How long have you been alive?", JOptionPane.WARNING_MESSAGE);
   }      
   int birth = Integer.parseInt(birthString);
   String currentString = JOptionPane.showInputDialog(
           null, "Enter cureent year: ", "How long have you been alive?",
           JOptionPane.QUESTION_MESSAGE);
   int current = Integer.parseInt(currentString);
   Pattern c = Pattern.compile("[A-Z,a-a,&%$#@!()*^]");
   Matcher n = c.matcher(currentString);     
   if (n.find()){
       JOptionPane.showMessageDialog(null, 
             "That doesn't look like numbers to me... Try again.",
             "How long have you been alive?", JOptionPane.WARNING_MESSAGE);
   }

如果有人输入除了数字以外的任何内容，它会给出对话框消息“这看起来不像我的数字......再试一次”，我想这样做。唯一的问题是它不会那样做，程序只是错误。任何帮助将不胜感激，我知道这是一个小的我做错了，只是找不到它。

Answer 1

你想要匹配一年，为什么不使用更简单的正则表达式。 \\d+将匹配一个或多个整数字符。 Matcher#matches会在完整的String：

上进行匹配

if (!birthString.matches("\\d+")) {
   JOptionPane.showMessageDialog(null,
    "That doesn't look like numbers to me... Try again.",
     "How long have you been alive?", JOptionPane.WARNING_MESSAGE);
}

请参阅：Pattern

遇到JoptionPane验证问题

1 个答案: