Checking “”


“” is not valid


Checking “123”


“123” is not valid


Checking “123456”


“123456” is not valid


Checking “12345-1234”


“12345-1234” is valid


Checking “12a34”


“12a34” is not valid


Checking “12345”


“12345” is valid


Checking “joe”


“joe” is not valid


Checking “34fj1”


“34fj1” is not valid