我不能为我的生活弄清楚为什么这段代码不会更新数据库表'产品'。我已经有一个人在家看着它，但她没有任何线索。任何帮助将不胜感激。
edit_products.php
<?php
$product = find_product_by_id($_GET["id"]);
if (!$product) {
// admin ID was missing or invalid or
// admin couldn't be found in database
safe_redirect("manage_products.php");
}
?>
<?php
if (isset($_POST['submit'])) {
// Process the form
$id = $product["id"];
$product_id = mysql_prep($_POST["product_id"]);
$product_name = mysql_prep($_POST["product_name"]);
$product_image = mysql_prep($_POST["product_image"]);
$highres_image = mysql_prep($_POST["highres_image"]);
$linedraw_image = mysql_prep($_POST["linedraw_image"]);
$product_video = mysql_prep($_POST["product_video"]);
$product_pdf = mysql_prep($_POST["product_pdf"]);
$product_keywords = mysql_prep($_POST["product_keywords"]);
$product_description = mysql_prep($_POST["product_description"]);
$product_enabled = mysql_prep($_POST["product_enabled"]);
$product_weight = mysql_prep($_POST["product_weight"]);
$product_length = mysql_prep($_POST["product_length"]);
$product_width = mysql_prep($_POST["product_width"]);
$product_height = mysql_prep($_POST["product_height"]);
$product_url = mysql_prep($_POST["product_url"]);
// validations
$required_fields = array("product_id", "product_name", "product_image", "product_description");
validate_presences($required_fields);
$fields_with_max_lengths = array("product_id" => 20);
validate_max_lengths($fields_with_max_lengths);
if (empty($errors)) {
// Perform Update
$query = "UPDATE products SET ";
$query .= "product_id = '{$product_id}', ";
$query .= "product_name = '{$product_name}', ";
$query .= "product_image = '{$product_image}', ";
$query .= "highres_image = '{$highres_image}', ";
$query .= "linedraw_image = '{$linedraw_image}', ";
$query .= "product_video = '{$product_video}', ";
$query .= "product_pdf = '{$product_pdf}', ";
$query .= "product_keywords = '{$product_keywords}', ";
$query .= "product_description = '{$product_description}', ";
$query .= "product_enabled = '{$product_enabled}', ";
$query .= "product_weight = '{$product_weight}', ";
$query .= "product_length = '{$product_length}', ";
$query .= "product_width = '{$product_width}', ";
$query .= "product_height = '{$product_height}', ";
$query .= "product_url = '{$product_url}', ";
$query .= "WHERE id = {$id} ";
$query .= "LIMIT 1";
$result = mysqli_query($connection, $query);
if ($result && mysqli_affected_rows($connection) == 1) {
// Success
$_SESSION["message"] = "Product updated.";
safe_redirect("manage_products.php");
} else {
// Failure
$_SESSION["message"] = "Product update failed.";
}
}
// This is probably a GET request
} // end: if (isset($_POST['submit']))
?>
<?php $layout_context = "admin"; ?>
<?php include("includes/layouts/header.php"); ?>
<?php echo message(); ?> <?php echo form_errors($errors); ?>
<h2>Edit Product: <?php echo htmlentities($product["product_id"]); ?></h2>
<form action="edit_product.php?id=<?php echo urlencode($product["id"]); ?>" method="post">
<p>Product ID:
<input name="product_id" type="text" value="<?php echo htmlentities($product["product_id"]); ?>" size="15" />
</p>
<p>Product Name:
<input name="product_name" type="text" value="<?php echo htmlentities($product["product_name"]); ?>" size="45" />
</p>
<p>Product Image:
<input name="product_image" type="text" value="<?php echo htmlentities($product["product_image"]); ?>" size="45" />
</p>
<p>High Res Image:
<input name="highres_image" type="text" value="<?php echo htmlentities($product["highres_image"]); ?>" size="45" />
</p>
<p>Line Drawing:
<input name="linedraw_image" type="text" value="<?php echo htmlentities($product["linedraw_image"]); ?>" size="45" />
</p>
<p>Product Video:
<input name="product_video" type="text" value="<?php echo htmlentities($product["product_video"]); ?>" size="45" />
</p>
<p>Product PDF:
<input name="product_pdf" type="text" value="<?php echo htmlentities($product["product_pdf"]); ?>" size="45" />
</p>
<p>Product Keywords:
<input name="product_keywords" type="text" value="<?php echo htmlentities($product["product_keywords"]); ?>" size="45" />
</p>
<p>Product Description:
<input name="product_description" type="text" value="<?php echo htmlentities($product["product_description"]); ?>" size="45" />
</p>
<p>Product Enabled:
<input name="product_enabled" type="text" value="<?php echo htmlentities($product["product_enabled"]); ?>" size="5" />
</p>
<p>Product Weight:<input name="product_weight" type="text" value="<?php echo htmlentities($product["product_weight"]); ?>" size="5" /> Length: <input name="product_length" type="text" value="<?php echo htmlentities($product["product_length"]); ?>" size="5" /> Width: <input name="product_width" type="text" value="<?php echo htmlentities($product["product_width"]); ?>" size="5" /> Height: <input name="product_height" type="text" value="<?php echo htmlentities($product["product_height"]); ?>" size="5" />
</p>
<p>Product URL:
<input name="product_url" type="text" value="<?php echo htmlentities($product["product_url"]); ?>" size="45" />
</p>
<input type="submit" name="submit" value="Edit Product" />
</form>
这是函数find_product_by_id
function find_product_by_id($product_id) {
global $connection;
$safe_product_id = mysqli_real_escape_string($connection, $product_id);
$query = "SELECT * ";
$query .= "FROM products ";
$query .= "WHERE id = {$safe_product_id} ";
$query .= "LIMIT 1";
$product_set = mysqli_query($connection, $query);
confirm_query($product_set);
if($product = mysqli_fetch_assoc($product_set)) {
return $product;
} else {
return null;
}
}
答案 0 :(得分：2)
问题是一个尾随的逗号，正如评论中所指出的那样。但真正的问题是缺乏错误检查。如果你有下面的代码示例，你会立即发现问题：
if ( ! $result = mysqli_query($connection, $query))
{
echo 'ERROR: '.mysqli_error($connection);
}
这会向您指出您的查询无效。