首先,我是新来的人。我需要问一个问题。
Scanner klavye = new Scanner(System.in);
System.out.println("DDD-DD-DDDD enter bank number digit: ");
String hesapNo = klavye.nextLine();
if(hesapNo.length() != 11) {
System.out.println("You need to enter number with 11 digit");
}
else {
if(hesapNo.charAt(3) == '-' && hesapNo.charAt(6) == '-') {
System.out.println(hesapNo + " is valid");
}
else {
System.out.println(hesapNo + " is not valid");
}
}
我只想输入数字,但是如果我这样写:
ABC-DC-SMND
“计数有效”
我怎么解决这个问题?
感谢您的关注。
最佳答案
您可以使用正则表达式和循环来提示用户,直到输入有效为止。
Scanner klavye = new Scanner(System.in);
System.out.println("DDD-DD-DDDD enter bank number digit: ");
String hesapNo;
final String regexPattern = "\\d{3}-\\d{2}-\\d{4}";
do {
hesapNo = klavye.nextLine();
System.out.println("You need to enter a number with 11 digit with pattern: DDD-DD-DDDD");
}
while(!hesapNo.matches(regexPattern));
System.out.println(hesapNo + " is valid");