Single dash phone number - regex validation

Question

我需要一个简单的正则表达式来验证形式为xy的电话号码，其中x和y可以表示任意数字，而破折号是可选的，但是如果确实显示，则大多数出现在字符串中（破折号必须在数字处它的左和右）

Answer 1

/^\\d+(?:-\\d+)?$/应该可以解决问题。

Answer 2

/^\\d+(-\\d+)?$/) seems to work. It matches one or more leading digits, with an optional "hyphen followed by one or more digits".

#!/usr/bin/perl
#
@A = ( "1-2",
       "-12",
       "12-",
       "123-1234",
       "1-",
       "-1",
       "123",
       "1",
       "foo-bar",
       "12foo34",
       "foo12-34",
       "12f-o34",
       );

foreach (@A) {
  if (/^\d+(-\d+)?$/) {
    print "\"$_\" is a phone number\n";
  } else{
    print "\"$_\" is NOT a phone number\n";
  }
}

gives:

$ ./phone.pl 
"1-2" is a phone number
"-12" is NOT a phone number
"12-" is NOT a phone number
"123-1234" is a phone number
"1-" is NOT a phone number
"-1" is NOT a phone number
"123" is a phone number
"1" is a phone number
"foo-bar" is NOT a phone number
"12foo34" is NOT a phone number
"foo12-34" is NOT a phone number
"12f-o34" is NOT a phone number