php - 更新查询中的空表单字段的preg_match问题

Question

如果表单字段为空，则以下标记错误，如果在表单输入中输入了除字母以外的任何内容，则标记错误。

if (empty($_POST["feedtitle"])) {
    $has_errors = true;
    $feedtitleErr = "Enter feed title";
} elseif (preg_match('/[^a-zA-Z]/i',$_POST["feedtitle"])) {
    $has_errors = false;
    $feedtitleErr = "Enter text only";
} else {
    $feedtitle = validate_input($_POST["feedtitle"]);
}

创建表单时，这可以正常工作。然而，当编辑表格数据时，输入是空的，空字段错误“输入提要标题”不会​​触发，如果我输入除字母以外的任何内容，例如数字没有传递值，即变量$ feedtitle为空。如果我输入文字，它会保存。

我认为查询不是问题。

$Query = "UPDATE ccregisterfeed SET author='$author', category='$category',
copyright='$copyright', feeddescription='$feeddescription', feedtitle='$feedtitle',
websitelink='$websitelink', imagelink='$imagelink', imagetitle='$imagetitle',
subtitle='$subtitle' WHERE id='$feedid' AND username ='$user'";

全文

<?php
include "connect.php";
require "authenticate.php";
error_reporting(E_ERROR);
$message = $_GET['message'];
$user = $_SESSION['UserName'];

//declare form field and form field error variables
$authorErr = $categoryErr = $copyrightErr = $feeddescriptionErr = $feedlinkErr = $feedtitleErr = $websitelinkErr = $imagelinkErr = $imagetitleErr = $subtitleErr = "";
$author = $category = $copyright = $feeddescription = $feedlink = $feedtitle = $websitelink = $imagelink = $imagetitle = $subtitle = "";

//form field validation
function validate_input($data)
{
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}

if (isset($_POST['Submit']))
{
$has_errors = false;
if (empty($_POST["author"])) {
$has_errors = true;
$authorErr = "Enter your name";
}else{
$author = validate_input($_POST["author"]);
}

if (empty($_POST["category"])) {
$has_errors = true;
$categoryErr = "Enter a category";
}else {
$category = validate_input($_POST["category"]);
}

if (empty($_POST["copyright"])) {
$has_errors = true;
$copyrightErr = "Enter copyright details";
} else {
$copyright = validate_input($_POST["copyright"]);
}

if (empty($_POST["feeddescription"])) {
$has_errors = true;
$feeddescriptionErr = "Enter feed description";
} else {
$feeddescription = validate_input($_POST["feeddescription"]);
}

if (empty($_POST["feedtitle"])) {
$has_errors = true;
$feedtitleErr = "Enter feed title";
} elseif (preg_match('/[^a-zA-Z]/i',$_POST["feedtitle"])) {
$has_errors = true;
$feedtitleErr = "Enter text only";
} else {
$feedtitle = validate_input($_POST["feedtitle"]);
}

if (empty($_POST["websitelink"])) {
$has_errors = true;
$websitelinkErr = "Enter link to website";
} else {
$websitelink = validate_input($_POST["websitelink"]);
}

if (empty($_POST["imagelink"])) {
$has_errors = true;
$imagelinkErr = "Enter link to image";
} else {
$imagelink = validate_input($_POST["imagelink"]);
}

if (empty($_POST["imagetitle"])) {
$has_errors = true;
$imagetitleErr = "Enter image name";
} else {
$imagetitle = validate_input($_POST["imagetitle"]);
}

if (empty($_POST["subtitle"])) {
$has_errors = true;
$subtitleErr = "Enter feed subtitle";
} else {
$subtitle = validate_input($_POST["subtitle"]);
}

// var_dump ($date);
// var_dump ($feedlink);
// var_dump ($feeddescription);

//write edited data into tables matching logged in user with their data
$feedid = mysql_real_escape_string($_POST['feedid']);

$date = date("Y-m-d H:i:s");

$feeddescription = str_replace("_", "", $feeddescription);
$feeddescription = str_replace("-", "", $feeddescription);
$feeddescription = str_replace("!", "", $feeddescription);
$feeddescription = str_replace("#", "", $feeddescription);
$feeddescription = str_replace("'", "", $feeddescription);

$Query = "UPDATE ccregisterfeed SET author='$author', category='$category', copyright='$copyright', feeddescription='$feeddescription', feedtitle='$feedtitle', websitelink='$websitelink', imagelink='$imagelink', imagetitle='$imagetitle', subtitle='$subtitle' WHERE id='$feedid' AND username ='$user'";

if($sql = mysql_query($Query)) {
header("location: rss.php");
// header("location: feededit.php");
} else {
die("Query was: $Query. Error: ".mysql_error());
}
}

//show logged in user their updated data
$user = $_SESSION['UserName'];
$result = mysql_query("SELECT * FROM ccregisterfeed WHERE username = '$user'") or die(mysql_error());
while($row = mysql_fetch_array($result)){
$id=$row['id'];
$author = $row['author'];
$category = $row['category'];
$copyright = $row['copyright'];
$feeddescription = $row['feeddescription'];
$feedtitle = $row['feedtitle'];
$websitelink = $row['websitelink'];
$imagelink = $row['imagelink'];
$imagetitle = $row['imagetitle'];
$subtitle = $row['subtitle'];
}

//delete form and image data when users clicks delete button
if (isset($_POST['Delete'])){
$deleteuser = $_POST['Delete'];
mysql_query("DELETE FROM ccregisterfeed WHERE id = '$deleteuser'");
mysql_query("ALTER TABLE ccregisterfeed AUTO_INCREMENT = 1");
$message = 'Feed Deleted';
header("Location: feededit.php?&message=".urlencode($message));
}
?>

<!doctype html>
<html>
<head>
<meta charset="utf-8">

<form action="feededit.php" method="post" enctype="multipart/form-data" name="edit" id="editfeed">

<fieldset>
<div class="legendcreate">Feed Edit</div>

<div class="feedcontainer">
<div class="feedcontainerinner">

<div><label class="labelshow">Author</label><input id="author" class="insetfeed" name="author" type="text" placeholder="Author" value="<?PHP print $author ; ?>"/><p class="errorinput"><?php echo $authorErr;?></p></div>

<?php if(isset($_GET['message']) && !empty($message)): ?>
<div class="messagebox">
<?php echo $message ?>
</div>
<?php endif; ?>

<div><label class="labelshow">Category</label><input id="category" class="insetfeed" name="category" type="text" placeholder="Category" value="<?PHP print $category; ?>"/><p class="errorinput"><?php echo $categoryErr;?></p></div>

<div><label class="labelshow">Copyright</label><input id="copyright" class="insetfeed" name="copyright" type="text" placeholder="Copyright" value="<?PHP print $copyright; ?>"/><p class="errorinput"><?php echo $copyrightErr;?></p></div>

<div><label class="labelshow">Feed Title</label><input id="feedtitle" class="insetfeed" name="feedtitle" type="text" placeholder="Feed Title" value="<?PHP print $feedtitle; ?>"/><p class="errorinput"><?php echo $feedtitleErr;?></p></div>

<div><label class="labelshow">Website Link</label><input id="websitelink" class="insetfeed" name="websitelink" type="text" placeholder="Website Link" value="<?PHP print $websitelink; ?>"/><p class="errorinput"><?php echo $websitelinkErr;?></p></div>

<div><label class="labelshow">Image Link</label><input id="imagelink" class="insetfeed" name="imagelink" type="text" placeholder="Image Link" value="<?PHP print $imagelink; ?>"/><p class="errorinput"><?php echo $imagelinkErr;?></p></div>

<div><label class="labelshow">Image Title</label><input id="imagetitle" class="insetfeed" name="imagetitle" type="text" placeholder="Image Title" value="<?PHP print $imagetitle; ?>"/><p class="errorinput"><?php echo $imagetitleErr;?></p></div>

<div><label class="labelshow">Subtitle</label><input id="subtitle" class="insetfeed" name="subtitle" type="text" placeholder="Subtitle" value="<?PHP print $subtitle; ?>"/><p class="errorinput"><?php echo $subtitleErr;?></p></div>

<div><textarea id="description" name="feeddescription" class="textareadescription" placeholder="Enter feed description"><?php
    $out = htmlspecialchars_decode($feeddescription); 
    $out = str_replace( '\n', '<br />', $out ); 
    echo $out; 
    ?></textarea>

<div class="submit"><input name="Submit" type="submit" class="submitbtn" value="Save"/></div>
<div class="delete"><input name="deletebtn" type="submit" class="resetbtn" value="Delete"/></div>

<input type="hidden" name="feedid" value="<?phpecho $id;?>"/>

</div>
</div>
</div>

</form>
</fieldset>