我是 php 新手，我正在尝试从这里修改代码：http://www.w3schools.com/php/php_file_upload.asp http://www.w3schools.com/php/php_file_upload.asp文件上传后保留在同一页面上。
页面显示以下错误（文件上传之前但文件上传之后不显示）：
Notice: Undefined index: fileToUpload in C:\xampp\htdocs\test-site\index.php on line 12
Sorry, file already exists.
Notice: Undefined index: fileToUpload in C:\xampp\htdocs\test-site\index.php on line 38
Sorry, only JPG, JPEG, PNG & GIF files are allowed.Sorry, your file was not uploaded.
无论如何，文件上传正常。
这是代码：
<!DOCTYPE html>
<html>
<body>
<form action="<?php $_SERVER['PHP_SELF'] ?>" method="post" enctype="multipart/form-data">
Select image to upload:
<input type="file" name="fileToUpload" id="fileToUpload" class="upload_file">
<input type="submit" value="Upload Image" name="submit">
</form>
<?php
$target_dir = "uploads/";
$target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]);
$uploadOk = 1;
$imageFileType = pathinfo($target_file,PATHINFO_EXTENSION);
// Check if image file is a actual image or fake image
if(isset($_POST["submit"]))
{
$check = getimagesize($_FILES["fileToUpload"]["tmp_name"]);
if($check !== false)
{
echo "File is an image - " . $check["mime"] . ".";
echo '<a href="'.$target_file.'">Download you file here</a>';
$uploadOk = 1;
}
else
{
echo "File is not an image.";
$uploadOk = 0;
}
}
// Check if file already exists
if (file_exists($target_file))
{
echo "Sorry, file already exists.";
$uploadOk = 0;
}
// Check file size
if ($_FILES["fileToUpload"]["size"] > 500000)
{
echo "Sorry, your file is too large.";
$uploadOk = 0;
}
// Allow certain file formats
if($imageFileType != "jpg" && $imageFileType != "png" && $imageFileType != "jpeg"&& $imageFileType != "gif" )
{
echo "Sorry, only JPG, JPEG, PNG & GIF files are allowed.";
$uploadOk = 0;
}
// Check if $uploadOk is set to 0 by an error
if ($uploadOk == 0)
{
echo "Sorry, your file was not uploaded.";
// if everything is ok, try to upload file
}
else
{
if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $target_file))
{
echo "The file ". basename( $_FILES["fileToUpload"]["name"]). " has been uploaded.";
}
else
{
echo "Sorry, there was an error uploading your file.";
}
}
?>
</body>
</html>
