html - PHP Contact form, True/False in Email if CheckBox is Checked -

i have file called send_form_email.php , i'm trying send e-mail me trues/falses or way of signifying checkboxes checked. think there's wrong way i've tried expand found on internet - right sends form okay, not information items checked.

these ones checkboxes on web form:

$farmscale = $_post['farmscale']; // not required $nutrients = $_post['nutrients']; // not required $smallscale = $_post['smallscale']; // not required $plantdesign = $_post['plantdesign']; // not required $industrialscale = $_post['industrialscale']; // not required $engineering = $_post['engineering']; // not required $stgs = $_post['stgs']; // not required $compsupply = $_post['compsupply']; // not required 

but main file, , i'm not sure how true/fales value spit out in email sends. please gentle... still kinda new stuff.

    <?php     if(isset($_post['email'])) {          // edit 2 lines below required         $email_to = "michaelomchenry@gmail.com";         $email_subject = "inquiry enginuityenergy.com";           function died($error) {             // error code can go here             echo "we sorry, there error(s) found form submitted. ";             echo "these errors appear below.<br /><br />";             echo $error."<br /><br />";             echo "please go , fix these errors.<br /><br />";             die();         }          // validation expected data exists         if(!isset($_post['first_name']) ||             !isset($_post['last_name']) ||             !isset($_post['email']) ||             !isset($_post['telephone']) ||             !isset($_post['country']) ||             !isset($_post['comments'])) {             died('we sorry, there appears problem form submitted.');                }          $first_name = $_post['first_name']; // required         $last_name = $_post['last_name']; // required         $email_from = $_post['email']; // required         $telephone = $_post['telephone']; // not required         $country = $_post['country']; // not required         $comments = $_post['comments']; // required         $farmscale = $_post['farmscale']; // not required         $nutrients = $_post['nutrients']; // not required         $smallscale = $_post['smallscale']; // not required         $plantdesign = $_post['plantdesign']; // not required         $industrialscale = $_post['industrialscale']; // not required         $engineering = $_post['engineering']; // not required         $stgs = $_post['stgs']; // not required         $compsupply = $_post['compsupply']; // not required          $error_message = "";         $email_exp = '/^[a-za-z0-9._%-]+@[a-za-z0-9.-]+\.[a-za-z]{2,4}$/';       if(!preg_match($email_exp,$email_from)) {         $error_message .= 'the email address entered not appear valid.<br />';       }         $string_exp = "/^[a-za-z .'-]+$/";       if(!preg_match($string_exp,$first_name)) {         $error_message .= 'the first name entered not appear valid.<br />';       }       if(!preg_match($string_exp,$last_name)) {         $error_message .= 'the last name entered not appear valid.<br />';       }       if(strlen($comments) < 2) {         $error_message .= 'the comments entered not appear valid.<br />';       }       if(strlen($error_message) > 0) {         died($error_message);       }         $email_message = "form details below.\n\n";          function clean_string($string) {           $bad = array("content-type","bcc:","to:","cc:","href");           return str_replace($bad,"",$string);         }          $email_message .= "first name: ".clean_string($first_name)."\n";         $email_message .= "last name: ".clean_string($last_name)."\n";         $email_message .= "email: ".clean_string($email_from)."\n";         $email_message .= "telephone: ".clean_string($telephone)."\n";         $email_message .= "comments: ".clean_string($comments)."\n";         $email_message .= "country: ".clean_string($country)."\n";         $email_message .= "farm scale: ".$farmscale."\n";         $email_message .= "nutrients: ".$nutrients."\n";         $email_message .= "small scale: ".$smallscale."\n";         $email_message .= "plant design: ".$plantdesign."\n";         $email_message .= "industrial scale: ".$industrialscale."\n";         $email_message .= "engineering: ".$engineering."\n";         $email_message .= "stgs: ".$stgs."\n";         $email_message .= "component supply: ".$compsupply."\n";       // create email headers     $headers = 'from: '.$email_from."\r\n".     'reply-to: '.$email_from."\r\n" .     'x-mailer: php/' . phpversion();     @mail($email_to, $email_subject, $email_message, $headers);       ?>      <!-- include own success html here -->      <center>         <h1>thank contacting us.</h1>         <br><br>          <p>we in touch soon.</p>         <p>in meantime, head <a href="http://www.enginuityenergy.com">main site</a> learn more enginuity energy's innovative biomass gasification.<p>     </center>       <?php     }     ?> 

i've got on issue inserting new input hidden this:

<input type="hidden" name="farmscale" value="n" /> <input type="checkbox" name="farmscale" value="y" /> 

you can every checkbox or radio button.