我想实现一个简单的图像上传器，它存储标题、登录的用户（$_SESSION['username']）和文件的保存路径。
会话正在工作，代码正确，数据库表存在，但它只写入"path"值，"username"answers"caption"在数据库中保持为空。
这是上传的代码：
if ((($_FILES["file"]["type"] == "image/gif")
|| ($_FILES["file"]["type"] == "image/jpeg")
|| ($_FILES["file"]["type"] == "image/jpg")
|| ($_FILES["file"]["type"] == "image/pjpeg")
|| ($_FILES["file"]["type"] == "image/x-png")
|| ($_FILES["file"]["type"] == "image/png"))
&& ($_FILES["file"]["size"] < 5000000)
&& in_array($extension, $allowedExts)) {
if ($_FILES["file"]["error"] > 0) {
echo "Return Code: " . $_FILES["file"]["error"] . "<br>";
} else {
if (file_exists("upload/" . $_FILES["file"]["name"])) {
echo $_FILES["file"]["name"] . " already exists. ";
} else {
move_uploaded_file($_FILES["file"]["tmp_name"],
"upload/" . $_FILES["file"]["name"]);
$caption = $_POST['caption'];
$uploaderUsername = $_SESSION['username'];
$path = "upload/" . $_FILES['file']['name'];
mysql_connect("localhost","root","") or die(mysql_error());
mysql_select_db("mydb") or die(mysql_error());
mysql_query("INSERT INTO images (caption,username,path) VALUES
('$caption','$uploaderUsername','$path')");
header('Location: members.php');
}
}
} else {
echo "Invalid file";
}
我想这部分有问题：
$caption = $_POST['caption'];
$uploaderUsername = $_SESSION['username'];
$path = "upload/" . $_FILES['file']['name'];
mysql_connect("localhost","root","") or die(mysql_error());
mysql_select_db("mydb") or die(mysql_error());
mysql_query("INSERT INTO images (caption,username,path) VALUES
('$caption','$uploaderUsername','$path')");
header('Location: members.php');
添加到上方的注释中
"我看不出你在试图访问会话变量之前调用session_start（）。（这恰好是你没有得到的两个变量之一：O）。在你的表单中，确保你为标题输入设置了name=‘caption’"
使用您提供的代码，实现您想要做的与类似的事情的标题
<form action="upload_file.php" method="post" enctype="multipart/form-data">
<label for="file">Filename:</label>
<input type="file" name="file" id="file"><br>
<label for="caption">Caption: </label>
<input type="text" id="caption" name="caption" placeholder="Add a caption here"><br>
<input type="submit" name="submit" value="Submit">
</form>