Common Phone validator RegEx , E-mail validator Regular Expression

I use custom validators to validate my forms email and phone numbers.
In most of the public website that I developed I use this two common javascript functions to work with ASP.NET validators.

<asp:textbox id="txtPhoneNumber" maxlength="13" runat="server"></asp:textbox>

<asp:customvalidator id="valPhone" runat="server" cssclass="ErrorLabel" errormessage="* required" clientvalidationfunction="validatePhone" controltovalidate="txtPhoneNumber" validateemptytext="true"></asp:customvalidator>

function validatePhone(sender, args)
{
if(args.Value.length > 0)
{
   var ex = /\(?([0-9]{3})\)?[-. ]?([0-9]{3})[-. ]?([0-9]{4})$/;
   var re = new RegExp(ex);

   if(re.exec(args.Value))
   {
       args.IsValid = true;
   }
   else
   {
       sender.errormessage= "* invalid";
       sender.innerHTML= sender.errormessage;
       args.IsValid = false;
   }   
}
else
{
   sender.errormessage= "* required";
   sender.innerHTML= sender.errormessage;
   args.IsValid = false;
}
}

function validateEmail(sender, args)
{
if(args.Value.length > 0)
{
   var ex = /^([a-zA-Z0-9_.+-])+@([a-zA-Z0-9_.-])+\.([a-zA-Z])+([a-zA-Z])+/;
   var re = new RegExp(ex );

   if(re.exec(args.Value))
   {
       args.IsValid = true;
   }
   else
   {
       sender.errormessage= "* invalid";
       sender.innerHTML= sender.errormessage;
       args.IsValid = false;
   }   
}
else
{
   sender.errormessage= "* required";
   sender.innerHTML= sender.errormessage;
   args.IsValid = false;
}
}