Question

我对Java很陌生。抱歉，这是一个la脚的问题。我有这段代码。这显然不是全部。

    char option = scan.next().charAt(0); 

    for (option !='a'||option !='b'||option !='c'||option !='d'||option !='e'||option !='f'||option !='q') {
        System.out.println("Please pick an option from the menu above");
    }

    int lengthOne = stringOne.length(); //Getting the lengths for each string           
    int lengthTwo = stringTwo.length();

    if (option == 'a'|| option == 'A') { //If the user inputs a
        if (lengthOne == lengthTwo) { //If both lengths are equal
            System.out.println("The strings are the same length");
        }

正在寻找有关我应将此代码用于哪个循环的建议。选项为A-F，然后按Q退出。

Answer 1

在循环内添加扫描。

char option = scan.next().charAt(0); 

while (option !='a'||option !='b'||option !='c'||option !='d'||option !='e'||option !='f'||option !='q') {
    System.out.println("Please pick an option from the menu above");
    option = scan.next().charAt(0);
}

Answer 2

尝试一下

    Scanner scan = new Scanner(System.in);
    char option = scan.next().charAt(0); 

    while (option != 'a' && option !='b' && option != 'c'&& option !='d'&& option !='e'&& option !='f'&& option !='q') {
        System.out.println("Please pick an option from the menu above");
        option = scan.next().charAt(0);
    }

您将需要使用AND而不是OR，否则它将无法正常工作

Answer 3

while循环对于您要完成的工作似乎有些混乱。我会在“ do while”循环内使用Switch语句。

如果用户输入的内容与“大小写”不匹配，则会使用默认设置。

当用户输入“ q”退出时，boolean validSelection变成true，您将退出“ do while”循环。

    public static void main( String[] args )
{
    Scanner scan = new Scanner( System.in );

    boolean validSelection = false;

    do
    {
        System.out.println( "Please pick an option from the menu above" );
        char option = scan.next().charAt( 0 );
        switch( option )
        {
            case 'a':
                break;
            case 'b':
                break;
            case 'c':
                break;
            case 'd':
                break;
            case 'e':
                break;
            case 'f':
                break;
            case 'q':
                validSelection = true;
                break;
            default:
                System.out.println( "Choice invalid." );
                break;
        }
    }
    while( validSelection == false );
}
}

如何为此特定任务选择并编写循环？

3 个答案: