/**
  * Add Tax Rule
  */
 function addTaxRule()
 {
     if ($this->post['allstates'] == "true") {
         $this->post['state'] = null;
     } else {
         if (!isset($this->post['state'])) {
             // A specific state was not provided
             throw new FieldMissingException("state");
         }
     }
     // Create a new Tax Rule DBO
     $taxrule_dbo = new TaxRuleDBO();
     $taxrule_dbo->setCountry($this->post['country']);
     $taxrule_dbo->setState($this->post['state']);
     $taxrule_dbo->setRate($this->post['rate']);
     $taxrule_dbo->setAllStates($this->post['allstates'] == "true" ? "Yes" : "Specific");
     $taxrule_dbo->setDescription($this->post['description']);
     // Insert Tax Rule into database
     add_TaxRuleDBO($taxrule_dbo);
     // Success
     $this->setMessage(array("type" => "[TAX_RULE_CREATED]"));
     $this->post['success'] = "true";
 }