<asp:TextBox ID="RequestorPhone" runat="server" MaxLength="20" />
<asp:RequiredFieldValidator runat="server" ControlToValidate="RequestorPhone" Display="Dynamic" ErrorMessage="Phone # is required" />
<asp:RegularExpressionValidator ID="revPhone" runat="server" ControlToValidate="RequestorPhone" Display="Dynamic" ErrorMessage="Phone # is invalid" ValidationExpression="^(?:(?:+?1s*(?:[.-]s*)?)?(?:(s*([2-9]1[02-9]|[2-9][02-8]1|[2-9][02-8][02-9])s*)|([2-9]1[02-9]|[2-9][02-8]1|[2-9][02-8][02-9]))s*(?:[.-]s*)?)?([2-9]1[02-9]|[2-9][02-9]1|[2-9][02-9]{2})s*(?:[.-]s*)?([0-9]{4})(?:s*(?:#|x.?|ext.?|extension)s*(d+))?$" />
Credit: fatcat1111 @ stackoverflow.com
Originally Posted on January 9, 2015
Last Updated on October 26, 2015
Last Updated on October 26, 2015
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