这就是我所需要的,也是我所得到的。将数字3到10添加到哈希表中提示用户输入字符串,并显示相应的数字。使用循环和单个println语句,显示表中的所有值(字符串和整数)。我的主要问题是我不确定如何处理while循环。我只使用过一次while循环。
import java.util.*;
class HTDemo {
public static void main(String args[]) {
Hashtable<String, Integer> numbers = new
Hashtable<String, Integer>();
numbers.put("one", new Integer(1));
numbers.put("two", new Integer(2));
numbers.put("three", new Integer(3));
numbers.put("four", new Integer(4));
numbers.put("five", new Integer(5));
numbers.put("six", new Integer(6));
numbers.put("seven", new Integer(7));
numbers.put("eight", new Integer(8));
numbers.put("nine", new Integer(9));
numbers.put("ten", new Integer(10));
String number;
Scanner input = new Scanner(System.in);
System.out.println("Enter a number in word form: (Example: Five, Six, Seven): ");
number = input.next();
while () {
System.out.println("You entered: " + number + "nwhich is the interger: " + numbers);
}
}
}
这就是我得到的,这不符合说明:
以单词形式输入数字:(例如:五、六、七):
五个
您输入了:五个
哪个是整数:{3=3,6=6,10=10,7=7,9=9,1=1,5=5,4=4,2=2,8=8}
Scanner input = new Scanner(System.in);
System.out.println("Enter a number in word form: (Example: Five, Six, Seven): ");
// wait for input
String number = input.next();
// display value, using Map#get method
System.out.println(String.format("You've entered %s which is integer %s", number, numbers.get(number)));
// iterate over map entries using for (not while) loop
for (Map.Entry<String, Integer> e : numbers.entrySet()) {
System.out.println(String.format("Number:%s, integer:%s", e.getKey(), e.getValue()));
}
顺便说一句,你不应该忘记字符串是区分大小写的,即numbers.get("Seven")
将返回null
,因为你在那里放了"seven"
,而不是"Seven"
。