java - 尝试验证字符串输入时陷入 while 循环

Question

因此，我尝试以 DD/MM/YYYY 格式输入出生日期，输入的长度不能超过 10 个字符，并且我必须确保其格式正确，以避免用户输入类似 A51/1/1982 之类的内容，我认为至少据我所知，我已经正确编写了它:)，但在检查输入时，我现在永远陷入了 while 循环

       System.out.println("Please enter your date of birth in the format DD/MM/YYYY");
   dateOfBirth = scanner.nextLine(); //Read date of birth
   dob0 = dateOfBirth.substring(0);// to check char 0 is between 0-3
   dob1 = dateOfBirth.substring(1);// to check char 1 is between 0-9
   dob2 = dateOfBirth.substring(2);// to check char 2 is between /
   dob3 = dateOfBirth.substring(3);// to check char 3 is between 0-1
   dob4 = dateOfBirth.substring(4);// to check char 4 is between 0-9
   dob5 = dateOfBirth.substring(5);// to check char 5 is between /
   dob6 = dateOfBirth.substring(6);// to check char 6 is between 1-2
   dob7 = dateOfBirth.substring(7);// to check char 7 is between 0-9
   dob8 = dateOfBirth.substring(8);// to check char 8 is between 0-9
   dob9 = dateOfBirth.substring(9);// to check char 9 is between 0-9
   dob = dateOfBirth.length(); //convert string to int to check length
   while (dob !=10 || !dob0.matches("[0-3]+") || !dob1.matches("[0-9]+") ||      !dob2.matches("[/]+")
    || !dob3.matches("[0-1]+") || !dob4.matches("[0-9]+") || !dob5.matches("[/]+")
    || !dob6.matches("[1-2]+") || !dob7.matches("[0-9]+") || !dob8.matches("[0-9]+") 
    || !dob9.matches("[0-9]+"))//check all values
   {
   System.out.println("Please make sure you enter your date of birth in the format DD/MM/YYYY");
   dateOfBirth = scanner.nextLine();
   }

我猜我可能已经在这个问题上走了很长一段路了，但如果有任何帮助，我们将不胜感激:)

谢谢

Answer 1

您不会重新评估新的用户输入。仅输入第一行。输入新输入后，整个 dob0= .. dob = stuff 也应该进入 while 循环。