Newbie need help with form

I am trying to use functions to calculate the cost
i am not sure how to get my variable from my checkbox
and i need to calculate if the user is doing the one day conference he pays for one day meal plan if he does the two day conf he gets the two day meal plan and so on…
I was going to do it like if yes is checked

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html lang="EN" dir="ltr" xmlns="http://www.w3.org/1999/xhtml">

<style>

body
{
color:black;
font-size:20px;

}
h1
{
color:orange;
text-align:center;
font-size:30px;

}
p
{

font-family:"Times New Roman";
font-size:20px;

}
</style>

<title>MAJOR PROJECT 1 PHP </title>

</head>
<body>

<h1>Nerd Roundup </h1>


<form method = "POST"
      action = "http://localhost/Assignments php class/calculationprogress.php">
  <fieldset>
    <label>
      Please type your  first name:
    </label>
    <input type = "text"
           name = "fName"
           value = "" /> <br />
            <label>
      Please type your  Last name:
    </label>
    <input type = "text"
           name = "lName"
           value = "" /> <br />


    Please type your  city:
    <input type = "text"
           name = "city"
           value = "" /> <br />
             Please type your  State:
    <input type = "text"
           name = "state"
           value = "" /> <br />
    Please type your  Zipcode:
    <input type = "text"
           name = "zipCode"
           value = "" /> <br />

<label for="other">Anything else you want to add?</label>
 <textarea id="other" name="other"></textarea><br />
	




<fieldset>
  <legend>HOW MANY DAYS</legend>
  <input type = "checkbox"
         name = "chkOne"
         value = "100.OO" /><label>ONE DAY $100.00</label>
  <input type = "checkbox"
         name = "chkTwo"
         value = "175.00" /><label>TWO DAYS $175.00</label>
  <input type = "checkbox"
         name = "chkThree"
         value = "325.00" /><label>THREE DAYS $325.00</label>

<br />

	<fieldset>
  <legend>DO YOU WANT THE MEAL PLAN?</legend>
  <input type = "checkbox"
         name = "mealPlan"
         value = "yes" /><label>YES</label>

  <input type = "checkbox"
         name = "mealPlan"
         value = "no" /><label>NO</label>
<br />
<br />

<h1>NERD TRACK</h1>
  <select name = "track">
    <option value = "PROGRAMMING TRACK">PROGRAMMING TRACK</option>
    <option value = "NETWORKING TRACK">NETWORKING TRACK</option>
    <option value = "SECURITY TRACK">SECURITY TRACK</option>
    <option value = "WEB TRACK">WEB TRACK</option>
  </select>

  <button type = "submit">
    place order
  </button>
</fieldset>
</form>
</body>
</html>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html lang="EN" dir="ltr" xmlns="http://www.w3.org/1999/xhtml">
<head>
<style>
body
{

background-color:#FF00FF;
}
h1
{
color:orange;
text-align:center;
}
p
{
font-family:"Times New Roman";
font-size:20px;
}
h1 {text-align:center;
}
</style>
<title>Assignment3</title>
</head>
<body>

<h1>Personal Information </h1>

<?php
// define the variables
$confId = rand(1,1000);
$fName = $_POST["fName"];
$lName = $_POST ["lName"];
$city = $_POST ["city"];
$state = $_POST ["state"];
$zipCode = $_POST["zipCode"];
$other = $_POST ["other"];
$chkOne = $_POST["chkOne"];
$chkTwo = $_POST["chkTwo"];
$chkThree = $_POST["chkThree"];
$mealPlan = $_POST[""];
$confTotal = 0;
$no_errors = TRUE;
$total = 0;

checkInput();
calcPrice();
printConf();


//checkInput
function checkInput() {

if (filter_has_var(INPUT_POST, "chkOne")){
  print "<p>ONE DAY CONFERENCE</p> \
";
  $total += filter_input(INPUT_POST, "chkOne");

}

if (filter_has_var(INPUT_POST, "chkTwo")){
  print "<p>TWO DAY CONFERENCE</p> \
";
  $total += filter_input(INPUT_POST, "chkTwo");

}

if (filter_has_var(INPUT_POST, "chkThree")){
  print "<p>THREE DAY CONFERENCE</p> \
";
  $total += filter_input(INPUT_POST, "chkThree");

}
//end $total


if (filter_has_var(INPUT_POST, "mealPlan")){

}

if (filter_has_var(INPUT_POST, "noFood")){

}
// do they want the meal plan

$track = filter_input(INPUT_POST, "track");
// what conference track are they on


if(empty($fName))
{
 $no_errors = FALSE;

echo '***FIRST NAME FIELD REQUIRED***** <br />' ;

	
	}
	//get users first name



if(empty($lName))
{
$no_errors = FALSE;

 echo '****LAST NAME FIELD REQUIRED***** <br /> ';

	
	}
	// get users last name
	
if(empty($city))
{
$no_errors = FALSE;

 echo '****CITY FIELD REQUIRED***** <br /> ';

	}
	//get user city
	
if(empty($state))
{
$no_errors = FALSE;

 echo '***STATE NAME FIELD REQUIRED***** <br /> ';
	}
//get user state


if(empty($zipCode))
{
$no_errors = FALSE;

 echo '****ZIPCODE FIELD REQUIRED***** <br /> ';

	}
//get user zip code



if(empty($other))
{
$no_errors = FALSE;



 echo '****TEXT FIELD REQUIRED***** <br /> ';

}
//get user additional comments

	
if ($no_errors == FALSE) {

echo "<br> <a href='major1progress.html'>Go back to form</a>";
}
	}//end function checkInput
	
//beging function calculateCost
function calcPrice(){

global $total;
	$confTotal =filter_input(INPUT_POST,"confTotal");
	$total = filter_input (INPUT_POST, "total");
	$mealPlan = filter_input (INPUT_POST, "mealPlan");
	
	IF (! filter_has_var (INPUT_POST, "mealPlan" )){
	$total =="100" ; $confTotal = $total+= 50;
	}
	else if ($total=="175"){ $confTotal = $total +=75;
	}
	else if ($total =="225"){$confTotal = $total +=100;
$no_errors == TRUE;
	}}
//end function cacluclateCost






//begin function printConf
function printConf(){
global $no_errors;
$no_errors = FALSE;

if ($no_errors == TRUE) {
print  " <p> $fName $lName, <br />you have registered for Nerd Roundup 2013<br />
your planned track is $track<br />
<br /> You choose -confDay<br /> with -mPlan<br />
The total cost is: \\$$total <br />
	I hear the climate around $zipCode is great this time of year.
	<br />  Please make sure to bring cash, or your credit card to pay for the conference on the first day<br />
 	Your additional comments are as follows:
  	$other <br /> </p>
 	 <p>Your Nerd Roundup confirmation number is  $confId .</p> <br /> \
";

 }
 	}
 //end function printConf







?>

</body>
</html> 

If it’s one or two or three days then you should be using radio buttons, not check boxes. For yes or no you only need one check box, not two: checked = yes, not checked = no.

The data is made available to php in the variable $_POST which is an array. Print it out at the top of your process page to see what you are dealing with

echo "<pre>";
print_r $_POST;
echo "</pre>";

the way i explain checkboxes and radio or drown downs is …

If you’re looking to do Option a AND Option b AND Option c then use Checkboxes if you’re doing Option a OR Option b OR Option c use Radio Buttons…

as for Drop Downs if its ALOT of options then use Dropdown Single or Multi Selection

For Multiselection you put name=‘options’ this will post into an array of options

restarted my project, trying to get the calculations down first.
Its not doing it right, I need a little help please

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html lang="EN" dir="ltr" xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>calculate cose of convention</title>
<link rel = "stylesheet"
      type = "text/css"
      href = "checkDemo.css" />
</head>
<body>
<h1>how many days</h1>

<h2>calculate cost of convention</h2>

<form action = "http://localhost/Assignments php class/calculate.php"
      method = "post">

<fieldset>
  <legend>How Many Days</legend>
  <input type = "checkbox"
         name = "oneDay"
         value = "100" /><label>oneDay</label>
  <input type = "checkbox"
         name = "twoDays"
         value = "175" /><label>twoDays</label>
  <input type = "checkbox"
         name = "threeDays"
         value = "225" /><label>threeDays</label>
    
	<fieldset>
 Please Check If you would Like The Meal Plan Added to your total. 
    <input type="checkbox" name="mealPlan" value="Yes" />
<br />
<br />


  <button type = "submit">
    place order
  </button>
</fieldset>
</form>

</body>
</html>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html lang="EN" dir="ltr" xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>calculate please</title>
</head>

<body>
<?php

$confId = rand(1,1000);
$total =0;
$no_errors = TRUE;

//meal plan 

if(!isset($_POST['mealPlan']) && 
   $_POST['mealPlan'] == 'Yes') 
{	$mealPlan== 'Yes';
     $no_errors = FALSE;
echo '****MEAL CHOICE REQUIRED***** <br /> ';}
    
if (filter_has_var(INPUT_POST, "oneDay")){
  print "<p>You wanted oneDay</p> \
";
  $total += filter_input(INPUT_POST, "oneDay");
}

if (filter_has_var(INPUT_POST, "twoDays")){
  print "<p>You wanted  twoDays</p> \
";
  $total += filter_input(INPUT_POST, "twoDays");
}

if (filter_has_var(INPUT_POST, "threeDays")){
  print "<p>You wanted threeDays</p> \
";
  $total += filter_input(INPUT_POST, "threeDays");
}

else


 	if ($total == 100 && $mealPlan =='Yes');
 {$total += 50;
 } 




 
 	if ($total == 175  && $mealPlan =='Yes');
 {
 	($total += 75);
 	}

 

 if ($total == 225 && $mealPlan =='Yes');
 {
 ($total += 100);
 }}
  


 



print "<p>The total cost is: \\$$total</p> \

		our Nerd Roundup confirmation number is  $confId .</p> <br /> \
";
?>
</body>
</html>
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