웹개발자의 기지개

123456789101112131415161718192021input type="text" id="hp" name="hp" class="form-control" value="">span style="color:red;">ex) 010-2222-3333/span>  script>function addHyphenToPhoneNumber(phoneNumberInput) {    const phoneNumber = phoneNumberInput.value;    const length = phoneNumber.length;     if(length >= 9) {        let numbers = phoneNumber.replace(/[^0-9]/g, "")                    .replace(..