PHP表单验证使用'if'

Question

我目前正在构建一个用于个人网站的非常小的“联系”表单。

表单有效，并且每个验证“if”语句单独有效，但是，例如，如果我输入了有效的电子邮件地址和电话号码但将消息留空，电子邮件仍会发送并且我会收到成功消息。

我的猜测是将小的“if”语句包含在一个检查我的必填字段是否不为空的语句中，尽管我不确定如何正确执行此操作，因为它将多个“if”嵌套到一个中。

干杯

<?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

您的问题是，每次验证条件之一通过时，您都会将 $errors 重置回 ''：

        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 = '';
        }

您不应该这样做，只需将错误消息留给以前的任何内容即可。这样，当你走到最后时，$errors 将包含一个包含所有错误消息组合的字符串。由于可能有多条消息，您可能希望在每条消息的末尾添加一个中断：

        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>";
        }

对于电子邮件，您可能希望仅在实际填写内容时才显示“无效的电子邮件地址”，因此您还可以在确定格式是否有效之前检查以确保其中有内容与否：

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

Answer 2

根据提供的信息，我认为您应该像这样使用复杂的 if-elseif-else 语句：

`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;
} `

在您的特定情况下：

// 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 3

试试下面的代码对你有帮助。

<?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 = '';
            }
            }



        ?>