使用'if'的PHP表单验证

Question

I'm currently building a very small 'contact' form for use on a personal site.

The form works, and each validation 'if' statement works individually, however, if for example I input a valid email address and phone number but leave the message blank, the email still sends and I get the success message.

My guess would be to include the small 'if' statements into the one checking whether my required fields are not empty, though i'm not sure how to do this correctly as it is nesting multiple 'if's into one.

Cheers

<?php 
            // Validation goes here
            $errors = '';
            $success = 'Success! Your message has been sent. You should receive a reply within 48 hours.';

            $email = $_POST['email']; 
            $name = $_POST['thename']; 
            $comments = $_POST['comments'];
            $number = $_POST['number']; 

            if(empty($name) || empty($email) || empty($comments)) {
                $errors .= "Error: please input a name, email address and your message.";
            } else {
                $errors = '';
            }

            if (!preg_match("/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i", $email)) {
                $errors .= "Error: Invalid email address";
            } else {
                $errors = '';
            }

            if (!preg_match("/^\(?0( *\d\)?){9,10}$/", $number)) {
                $errors .= "Error: Invalid phone number";
            } else {
                $errors = '';
            }

        ?>

        <!-- Display red error box or green success box depending on which is true -->
        <?php if(!empty($errors)): ?>
            <div class="validationbox | errorsbox">
                <?php echo $errors; ?>
            </div>
        <?php elseif(empty($errors)): ?>
            <div class="validationbox | successbox">
                <?php echo $success; ?>
            </div>
            <?php 
                $message = ''; // Blank message to start with so we can append to it.

                // Construct the message
                $message .= "
                    Name: {$_POST['thename']};
                    Email: {$_POST['email']};
                    Number: {$_POST['number']};
                    Enquiry-type: {$_POST['enquiry-options']};
                    Message: {$_POST['comments']};
";
                // test@testdomain.com
                $to = 'test-email-deleted-for-stackoverflow'; 
                $subject = 'Message from Portfolio';
                $from = $_POST['thename'];
                // YourSite@domain.com
                $fromEmail = 'test-email-deleted-for-stackoverflow';
                $header = 'From: ' . $from . '<' . $fromEmail . '>';
                mail($to,$subject,$message,$header);
            ?>
        <?php endif; ?>
    <?php endif; ?>

Answer 1

Based on the information Supplied, i think you should use a complex if-elseif-else statement like so:

`if (condition) {
    code to be executed if this condition is true;
} elseif (condition) {
    code to be executed if this condition is true;
} else {
    code to be executed if all conditions are false;
} `

in your particular case:

// Validation goes here
                $errors = '';
                $success = 'Success! Your message has been sent. You should receive a reply within 48 hours.';

                $email = $_POST['email']; 
                $name = $_POST['thename']; 
                $comments = $_POST['comments'];
                $number = $_POST['number']; 

                if(empty($name) || empty($email) || empty($comments)) {
                    $errors .= "Error: please input a name, email address and your message.";
                } elseif(!preg_match("/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i", $email)) {
                    $errors = 'Error:invalid email';
                }elseif(!preg_match("/^\(?0( *\d\)?){9,10}$/", $number){
                    $errors .= "Error: Invalid phone number";

                } else {
                    //Do this on successful validation comes here
                }

Answer 2

Your problem is that you are resetting $errors back to '' each time one of your validation conditions passes:

        if(empty($name) || empty($email) || empty($comments)) {
            $errors .= "Error: please input a name, email address and your message.";
        } else {
            $errors = '';
        }

        if (!preg_match("/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i", $email)) {
            $errors .= "Error: Invalid email address";
        } else {
            $errors = '';
        }

        if (!preg_match("/^\(?0( *\d\)?){9,10}$/", $number)) {
            $errors .= "Error: Invalid phone number";
        } else {
            $errors = '';
        }

You shouldn't do that, just leave error messages to whatever it previously was. This way, when you get to the end, $errors will contain a string of all the error messages combined. Since there could be multiple messages, you may want to put a break a the end of each one:

        if(empty($name) || empty($email) || empty($comments)) {
            $errors .= "Error: please input a name, email address and your message.<br>";
        } 

        if (!preg_match("/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i", $email)) {
            $errors .= "Error: Invalid email address<br>";
        } 

        if (!preg_match("/^\(?0( *\d\)?){9,10}$/", $number)) {
            $errors .= "Error: Invalid phone number<br>";
        }

In the case of email, you may want to only display the 'invalid email address' only when something was actually filled in, so you could also check to ensure there is something in there, before you determine if the format is valid or not:

    if (!empty($email) && !preg_match("/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i", $email)) {

Answer 3

try below code it helps you.

<?php 
            // Validation goes here
            $errors = '';
            $success = 'Success! Your message has been sent. You should receive a reply within 48 hours.';

            $email = $_POST['email']; 
            $name = $_POST['thename']; 
            $comments = $_POST['comments'];
            $number = $_POST['number']; 

            if(empty($name) || empty($email) || empty($comments)) {
                $errors .= "Error: please input a name, email address and your message.";
            } else {
                   if (!preg_match("/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i", $email)) {
                $errors .= "Error: Invalid email address";
            } else {
                $errors = '';
            }

            if (!preg_match("/^\(?0( *\d\)?){9,10}$/", $number)) {
                $errors .= "Error: Invalid phone number";
            } else {
                $errors = '';
            }
            }



        ?>