隐藏手机号中间四位，包含其它字符

//隐藏手机中间几位
public function hidtel($phone){
 $IsWhat = preg_match('/(0[0-9]{2,3}[-]?[2-9][0-9]{6,7}[-]?[0-9]?)/i',$phone);
 if($IsWhat == 1){
 return preg_replace('/(0[0-9]{2,3}[-]?[2-9])[0-9]{3,4}([0-9]{3}[-]?[0-9]?)/i','$1****$2',$phone);
 }else{
 return  preg_replace('/(1[0-9]{1}[0-9])[0-9]{4}([0-9]{4})/i','$1****$2',$phone);
 }
}