Question

该程序所做的是接收用户输入的单词并以猪拉丁形式返回。翻译循环继续，直到用户输入＆＃34;退出＆＃34;。我的问题是，当程序执行并翻译单词时，在输入单词quit之后，它会翻译＆＃34;退出＆＃34;这是我不想要的。我知道它翻译的原因＆＃34;退出＆＃34;在完成之前，它是一个while while循环，但我仍然坚持如何创建一个while循环功能。我将如何更改程序以便退出＆＃34;退出＆＃34;是什么终止循环并且没有被翻译？例：字：退出 UIT-qay

    import java.util.Scanner;

public static void main(String[] args) {
    String word;

    Scanner input = new Scanner(System.in);
    do {
        System.out.print("Word: ");
        word = input.next();

        System.out.println(pigLatinWord(word));
        System.out.println();
    } while (!word.equalsIgnoreCase("quit"));
    System.out.println("Translation complete");
}

// --------------------------------------------------------
// Convert one word to pig Latin.
public static String pigLatinWord(String s) {
    String pigWord;
    if (isVowel(s.charAt(0))) {
        pigWord = s + "-way";
    } else if (s.startsWith("th") || s.startsWith("Th")) { // or
                                                            // (s.toUpperCase().startsWith("TH"))
        pigWord = s.substring(2) + "-" + s.substring(0, 2) + "ay";
    } else {
        pigWord = s.substring(1) + "-" + s.charAt(0) + "ay";
    }
    return pigWord;
}

// ---------------------------------------------
// Determines whether c is a vowel character

public static boolean isVowel(char c) {
    String vowels = "aeiouAEIOU";
    return (vowels.indexOf(c) >= 0); // when index of c in vowels is not -1,
                            // c is a vowel
}

}

Answer 1

在您有机会检查单词是否等于＆＃34;退出＆＃34;之前，您正在执行pigLatinWord(word)。您可以这样更改循环：

do {
    System.out.print("Word: ");
    word = input.next();
    if( "quit".equalsIgnoreCase(word) )
        break;
    System.out.println(pigLatinWord(word));
    System.out.println();
} while (true);

Answer 2

做{} while（）;通常不好用，尝试使用while（）{}代替。像这样：

Scanner input = new Scanner(System.in);
boolean shouldQuit = false;
while (!shouldQuit) {
    System.out.print("Word: ");
    word = input.next();

    if (word.equalsIgnoreCase("quit")) {
        shouldQuit = true;
    } else {
        System.out.println(pigLatinWord(word));
        System.out.println();
    }
}
System.out.println("Translation complete");

或者，如果您想坚持使用do {}，请参阅另一个答案。

Answer 3

这是一种可能的方式。但是，它不涉及不使用do-while。

//This is an infinite loop, except that we have our exit condition inside the 
//body that'll forcibly break out of the loop.
while (true) {
    System.out.print("Word: ");
    word = input.next();
    if (word.equalsIgnoreCase("quit")) {
        break; //Whelp!  The user wants to quit.  Break the loop NOW
    }

    System.out.println(pigLatinWord(word));
    System.out.println();
}
System.out.println("Translation complete");

Answer 4

这个有用，我试过了：）

  String word;
  Scanner input = new Scanner(System.in);
  System.out.print("Word: ");
  while(!(word = input.next()).equalsIgnoreCase("quit")) {
     System.out.print("Word: ");
     System.out.println(pigLatinWord(word));
     System.out.println("fsfafa");
   } 
   System.out.println("Translation complete");

Java循环问题

4 个答案: