Java：如何从System.in.read中排除回车/换行

Question

我对此很陌生，正在研究一个教程，但想通过while循环来欣赏它，以便程序重复执行直到用户输入“ K”为止。 不幸的是，当输入了错误的字符时，这似乎读取了回车和换行符。 这意味着“ WRONG ”被输出三次而不是一次。 有什么方法可以排除这些字符，以便仅读取字符？ 提前致谢

class Guess{

    public static void main(String args[])
    throws java.io.IOException {
        char ch, answer ='K';


        System.out.println("I'm thinking of a letter between A and Z.");
        System.out.print("Can you guess it:");
        ch = (char) System.in.read(); //read a char from the keyboard

        while (ch != answer) {
        System.out.println("**WRONG**");
        System.out.println ("I'm thinking of a letter between A and Z.");
        System.out.print("Can you guess it:");
        ch = (char) System.in.read(); //read a char from the keyboard
        if (ch == answer) System.out.println("**Right**");

        }

    }
}

Answer 1

我建议使用Scanner并在用户点击return时读取该行，因为read会将return视为另一个字符，例如：

char answer ='K';
Scanner scanner = new Scanner(System.in);
System.out.println("I'm thinking of a letter between A and Z.");
System.out.print("Can you guess it:");
String ch = scanner.nextLine(); //read a char from the keyboard

while (ch.length() > 0 && ch.charAt(0) != answer) {
    System.out.println("**WRONG**");
    System.out.println ("I'm thinking of a letter between A and Z.");
    System.out.print("Can you guess it:");
    ch = scanner.nextLine();//read a char from the keyboard
}
System.out.println("**Right**");
scanner.close();

Answer 2

这只是陈述令。 尝试这个

public class Guess {

    public static void main(String args[])
            throws java.io.IOException {
        char ch, answer = 'K';

        System.out.println("I'm thinking of a letter between A and Z.");
        System.out.print("Can you guess it:");
        ch = (char) System.in.read(); //read a char from the keyboard

        while (ch != answer) {


            ch = (char) System.in.read(); //read a char from the keyboard
            if (ch == answer) {
                System.out.println("**Right**");
                break;
            }else{
                System.out.println("**WRONG**");
            }
            System.out.println("I'm thinking of a letter between A and Z.");
            System.out.print("Can you guess it:");

        }

    }

}