我正在尝试创建一个带有附件选项的表单，当表单在wordpress网站上提交时，它将发送到电子邮件。

我的代码工作正常，它以HTMLL表格格式向我的电子邮件地址发送电子邮件。此外，我能够发送附件使用代码。当我考虑附件文件扩展名和文件大小时，问题就出现了。我不知道如何限制文件的大容量，并只为一些允许的扩展名设置附件。

我的代码是：

<?php
//Setup an empty array.
$errors = array(); 
    if($_POST["submit"]) {
    $to = "[email protected]";
    $subject = "New reservations request";
    $hotel = $_POST["hotel_url"];
    $sender = $_POST["sendername"];
    $senderEmail = $_POST["senderEmail"];

    //Check the name and make sure that it isn\'t a blank/empty string.
    if(empty($sender)){
        //Blank string, add error to $errors array.        
        $errors[\'sendername\'] = "Please enter your name!";
    }

    /*  attachment */   
    move_uploaded_file($_FILES["attachment"]["tmp_name"],WP_CONTENT_DIR .\'/uploads/\'.basename($_FILES[\'attachment\'][\'name\']));
    $attachments = array(WP_CONTENT_DIR ."/uploads/".$_FILES["attachment"]["name"]);    

    if(empty($errors)){

        $mailBody = "<table border=\'1\'>
                       <tr>
                        <th>No</td>
                        <th>Item</td>
                        <th>Description</td>
                       </tr>
                       <tr>
                        <td>01</td>
                        <td>Hotel</td>
                        <td>$hotel</td>
                       </tr>
                       <tr>
                        <td>02</td>
                        <td>Name</td>
                        <td>$sender</td>
                       </tr>
                       <tr>
                        <td>03</td>
                        <td>E-Mail</td>
                        <td>$senderEmail</td>
                       </tr>
                    </table>";  

            $headers = array(\'From: \'.$_POST[\'sendername\'].\' <\'.$_POST[\'senderEmail\'].\'>\');

            $mail_sent = wp_mail( $to, $subject, $mailBody, $headers, $attachments );   
        }
    }

    if ($mail_sent) {
?>
    <p>Request sent</p>

<?php 
} else {
?>

<form id="" name="" action="<?php echo get_permalink(); ?>" method="post" enctype="multipart/form-data">
<input type="hidden" name="hotel_url" value="<?php echo get_permalink();?>" />

    <div class="section-heading"><h6>Your Details</h6></div>    
    <div class="label-input-wrapper">
        <div class="form-label">Name</div>
        <div class="form-input">
            <input type="text" name="sendername"/>
            <?php if(isset($errors[\'sendername\'])) { echo \'<span style="color: red">\'.$errors[\'sendername\'].\'</span>\'; } ?>
        </div>
    </div>

    <div class="label-input-wrapper">
        <div class="form-label">E-Mail</div>
            <div class="form-input">
                <input type="email" name="senderEmail" pattern="[a-z0-9._%+-]+@[a-z0-9.-]+\\.[a-z]{2,4}$" required value="<?PHP if(!empty($errors)) { echo $senderEmail;} ?>"/>
            </div>
    </div>  

    <label for=\'uploaded_file\'>Select A File To Upload:</label>
    <input type="file" name="attachment">

    <input type="submit" value="Submit" name="submit">
</form>

<?php
}
?>

上面的代码将附件发送到我的邮件，并将文件保存到我的上传目录中。我知道我必须在这附近做点什么/* attachment */ 允许文件的特定扩展名和大小。但如何做到这一点呢？如果我不得不允许的话。png。jpg。pdf格式，最大文件容量为1mb，我该怎么做？我必须在何处和哪些代码中修改上述代码？

$allowedExts = array("pdf", "jpg", "png");

$temp = explode(".", $_FILES["attachment"]["name"]);
$extension = end($temp);

if ((($_FILES["file"]["type"] == "image/pdf")
|| ($_FILES["file"]["type"] == "image/jpg")
|| ($_FILES["file"]["type"] == "image/png"))
&& ($_FILES["file"]["size"] < 1000000)
&& in_array($extension, $allowedExts)) {
  //your file upload code and other stuffs
} else {
  echo "Invalid file";
}