Luigi master Luigi master - 1 month ago 11
PHP Question

How do I make the uploaded file have a random name?

I am wondering how to make the image I have uploaded have a random name.
Using this, I can get a random string:

<?php
function generateRandomString($length = 10) {
return substr(str_shuffle(str_repeat($x='0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', ceil($length/strlen($x)) )),1,$length);
}

echo generateRandomString(); // OR: generateRandomString(24)


And I use this to upload it:

$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) {
$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" && $imageFileType != "bmp" ) {
echo "Sorry, only JPG, JPEG, PNG, BMP & 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 '<br>The file <img src="http://upimg.comxa.com/uploads/'. basename( $_FILES["fileToUpload"]["name"]). '"> has been uploaded.';
echo '<br>Direct URL: http://upimg.comxa.com/uploads/'. basename( $_FILES["fileToUpload"]["name"]);
} else {
echo "Sorry, there was an error uploading your file.";
}
}
?>


The problem is I don't know how.
I copied the code from w3schools, so I don't know entirely how it works.
Thanks.

Answer

If you use your function to change the variable $target_file, as this is where the file is saved.

So instead of this on line 2:

$target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]);

Replace it with this:

$target_file = $target_dir . generateRandomString();