header, session, php validation - php

Question

I'm having a big problem with my validation form. Basically I created a form that will, once submitted, redirect to another page. To do this I used header("location: aaaaa.php") and apparently it works. The problem is that by doing this the validation doesn't work anymore, in fact if I don't enter any data and press submit I'll be redirected to the second page without getting the errors. If I delete the header the validation works again.
Moreover I have a big problem with the session method. I tried different way of using it to transfer the data to the second page when pressed the button submit, but it doesn't work and no one until now was able to help me. In the code that I'm gonna put below I deleted the session method and I was hoping that you would help me with that.
London Flight Agency
if ($_SERVER["REQUEST_METHOD"] == "POST") {
if (empty($_POST["name"])) {
$nameErr = "Name is required";
} else {
$name =($_POST["name"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$name)) {
$nameErr = "Only letters and white space allowed";
}
}
if (empty($_POST["surname"])) {
$surnameErr = "Surname is required";
} else {
$surname =($_POST["surname"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$surname)) {
$surnameErr = "Only letters and white space allowed";
}
}
if (empty($_POST["email"])) {
$emailErr = "Email is required";
} else {
$email =($_POST["email"]);
// check if e-mail address is well-formed
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
$emailErr = "Invalid email format";
}
}
if (empty($_POST["telephone"])) {
$telephoneErr = "Number is required";
} else {
$telephone =($_POST["telephone"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[0-9\_]{7,20}/",$telephone)) {
$telephoneErr = "Enter correct telephone number";
}
}
if (empty($_POST["date"])) {
$dateErr = "Date is required";
} else {
$date =($_POST["date"]);
// check if name only contains letters and whitespace
if (!preg_match("~^\\d{1,2}[/.-]\\d{2}[/.-]\\d{4}$~",$date)) {
$dateErr = "Enter correct date of birth";
}
}
if (empty($_POST["luggage"])) {
$luggageErr = "Choose one of the options";
} else {
$luggage =($_POST["luggage"]);
}
$weight = $_POST['weight'];
$height = $_POST['height'];
if(isset($_POST['submit']))
{
$total = ($weight+$height)/10;
}
header("Location: thankyou.php");
}
?>
<h2 id="title">London Flight Agency</h2><!-- This tag is used to define HTML heading (h1 to h6), this particular one defines the most important heading -->
<form id="form" method="post" name="myForm" action = "<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>" onsubmit="return validateForm(this);"><!-- The <form> tag is used to create an HTML form for user input -->
<h4 class="subtitle"><strong>Personal Details</strong></h4>
<fieldset>
Enter here all your details (all of them are compulsory.)
<br />
<br />
<select name="Title" id="title" value="<?php echo $title;?>" onblur="validateSelect(name)">
<option value="empty">Title</option>
<option value="Mr">Mr</option>
<option value="Mrs">Mrs</option>
<option value="Miss">Miss</option>
<option value="Dr">Dr</option>
</select><br /><br />
<span class="validateError" id="titleError" style="display: none;">You must select a title!</span>
<span id="error8"><?php echo $titleErr;?></span>
<table
<tr>
<td><label for="firstname">First Name:</label></td>
<td><input type="text" name="name" value="<?php echo $name;?>" id="name" onblur="validateName(name)"></td>
<span id="nameError" style="display: none;"></span>
<span id="error1"><?php echo $nameErr;?></span>
</tr>
<tr>
<td><label for="surname">Surname:</label></td>
<td><input type="text" name="surname" value="<?php echo $surname;?>" id="name" onblur="validateSurname(surname)"></td>
<span id="surnameError" style="display: none;"></span>
<span id="error2"><?php echo $surnameErr;?></span>
</tr>
<tr>
<td><label for="email">Email address:</label></td>
<td><input type="text" name="email" value="<?php echo $email;?>" id="email" onblur="validateEmail(email)"></td>
<span id="emailError" style="display: none;"></span>
<span id="error3"><?php echo $emailErr;?></span>
</tr>
<tr>
<td><label for="telephone">Telephone No:</label></td>
<td><input type="text" name="telephone" value="<?php echo $telephone;?>" id="telephone" onblur="validateTelephone(telephone)"></td>
<span id="telephoneError" style="display: none;"></span>
<span id="error4"><?php echo $telephoneErr;?></span>
</tr>
<tr>
<td><label for="date">Date of birth:</label></td>
<td><input type="text" name="date" value="<?php echo $date;?>" id="date" onblur="validateDate(date)"></td>
<span id="dateError" style="display: none;"></span>
<span id="error5"><?php echo $dateErr;?></span>
</tr>
</table>
</fieldset>
<h4 class="subtitle"><strong>Flight Details</strong></h4>
<fieldset>
<p>Hand luggage:</p><br />
<input type="radio" name="luggage" <?php if (isset($luggage) && $luggage=="Yes") echo "checked";?>value="Yes" id = "myRadio" required onblur="myFunction()">Yes
<input type="radio" name="luggage" <?php if (isset($luggage) && $luggage=="No") echo "checked";?>value="No" id = "myRadio" required onblur="myFunction()">No
<span id="luggageError" style="display: none;"></span>
<span id="error6"><?php echo $luggageErr;?></span>
<br /><br />
<label for="extrabag">Include free extra bag</label>
<input type="checkbox" name="extra" id="check" value="bag">
<br />
<br />
<select name="option" id="card" onblur="validatePayment(card)">
<option value="empty">Payment Card</option>
<option value="Visa">Visa Debit Card</option>
<option value="MasterCard">MasterCard</option>
<option value="PayPal">PayPal</option>
<option value="Maestro">Mestro</option>
<option value="Visa Electron">Visa Electron</option>
</select><br />
<span class="validateError" id="cardError" style="display: none;">You must select your payment card!</span>
</fieldset>
<h4 class="subtitle"><strong>Luggage Details</strong></h4>
<fieldset>
<p>Enter weight and height of your luggage.</p>
Your Weight(kg): <input type="text" name="weight" size="7"><br />
Your Height(cm): <input type="text" name="height" size="7"><br />
<span id="error7"><?php echo $measureErr;?></span>
<input type="button" value="Tot. price" onClick="totalPrice()"><br /><br />
Total Price: <input type="text" name="total" value="<?php echo $total?>" size="10"><br /><br />
<input type="reset" value="Reset">
<input type="submit" value="Submit" name="submit">
</fieldset>
</form>
</body>
It doesn't show the first part of the code for I don't know which reason. I'll post it below:
London Flight Agency

Answer 1

The problem Is that you are checking if the method is post then redirect to the new page.
You must check if the your entries are valid then redirect.
For Example You can make an array of data and use array_push to push new data whenever there is something invalid and then check like this :
if( count( $array ) == 0 )
header('Location:YOUR_NEW_PAGE.php');
This is one of the simplest solutions you can implement.
Good luck