Allowing the customization of telephone numbers

Telephone numbers in different countries have different numbers of digits and different groupings of digits.

Guideline C13

<div class="ibm-alternate-code-sample"> <span>Allow the user to customize formatting of telephone numbers.</span> </div>

Don't assume that international users will know the international country code for their country. Note that in some countries, telephone numbers can contain nonnumeric characters such as "1-800-IBM-4YOU". In other countries, the plus sign (+) is an integral part of the telephone number such as "+81-3-1234-5678".