PHP regular expression to verify mobile phone number

Example, php regular expression to verify mobile phone and phone number.

function check_telnum1($telnum)
{
 $b1 = (preg_match("/^(0[0-9]{2,3}[-]?[2-9] [0-9]{6,7}[-]?[0-9]?)$/i",$telnum))?TRUE:FALSE;// Phone
 $b2 = (preg_match("/^(1 [358]{1}[0-9]{9})$/i",$telnum))?TRUE:FALSE;//Mobile phone
 return $b1 || $b2;
}