這裏我試圖通過輸入月份數來獲得輸出月份,但爲什麼我有錯誤 - 「月份字符串」可能沒有被初始化? - 爲什麼我沒有從「monthString」獲取輸出字符串?爲什麼變量必須被初始化?
爲什麼monthString必須被初始化?
import java.util.Scanner;
public class SwitchClass {
public static void main(String[]args)
{
Scanner input = new Scanner(System.in);
System.out.printf(" when did u born ? ");
int monthNumber = input.nextInt();
String monthString ;
switch (monthNumber)
{
case 1:
monthString = "January ";
break;
case 2:
monthString = "February ";
break;
case 3:
monthString = "March ";
break;
case 4:
monthString = "April ";
break;
case 5:
monthString = "May";
break;
case 6:
monthString = "June";
break;
case 7:
monthString = "July";
break;
case 8:
monthString = "August";
break;
case 9:
monthString = "September";
break;
case 10:
monthString = "October";
break;
case 11:
monthString = "November";
break;
case 12:
monthString = "December";
break;
}
System.out.println(monthString); }
}
或者創建一個默認開關的情況下,它給它一個值。 –
有道理,明白了。謝謝 – tun