0
我想驗證1或2的輸入。但是,使用此代碼,如果您輸入字母,它會使程序崩潰。isDigit validation
這怎麼解決?
System.out.print("Choice: ");
userSelection = keyboard.nextInt();
while (flag == 0)
{
if (userSelection == 1 || userSelection == 2)
{
flag = 1;
}
if(Character.isDigit(userSelection))
{
flag = 1;
}
else
{
flag = 0;
}
if (flag == 0)
{
//this is a system clear screen to clear the console
System.out.print("\033[H\033[2J");
System.out.flush();
//display a warning messege that the input was invalid
System.out.println("Invalid Input! Try again, and please type in selection 1 or selection 2 then hit enter");
System.out.print("Choice: ");
userSelection = keyboard.nextInt();
}
}
使用嘗試,趕上這樣,它不會破壞程序。你應該看看它在java中非常有用的文檔,你可以嘗試/捕獲一切:D –