Question

我是Java新手，我想创建一个布尔值，该布尔值检查char是否是列表的一部分，这样做的最佳方法是什么？我尝试使用枚举，但这似乎不起作用。有帮助吗？

Answer 1

您可以创建一个字符列表。并检查此列表是否包含指定的字符。请查看以下代码：

public static void main(String[] args) {
    List<Character> list = Arrays.asList('H', 'E', 'L', 'L');
    System.out.println(isCharExistInList('c', list));//false
    System.out.println(isCharExistInList('H', list));//true
  }

  private static boolean isCharExistInList(char c, List<Character> list){
    return list.contains(c);
  }

Answer 2

为此，您实际上可以遍历数组并检查要检查的字符是否存在于数组中，您可以执行以下操作：

public static void main(String[] args) {
        
        //use the wrapper class (Character) and not "char"
        ArrayList<Character> theList = new ArrayList<Character>(); //declare your ArrayList
        
        //insert items to the array list
        theList.add('a');
        theList.add('b');
        theList.add('c');
        theList.add('d');

        System.out.println(doesListContain('c', theList)); //call method
    }

    public static boolean doesListContain(char c, ArrayList<Character> list) {
        boolean isFound = false; //boolean var to keep track of the availability of character in list
        try {
            for (char character : list) {
                //iterate over array list using enhanced for loop
                if(c == character){
                    //if the character is found
                    isFound = true; //set boolean to true
                    break; //stop the loop
                }
            }
        } catch (Exception ex) {
            System.out.println(ex.getMessage());
        }
        return isFound; //return the boolean variable to the caller
    }

检查字符列表中是否包含字符

2 个答案: