Php form input file value

How to write value to an input type = file of an form using php

But what i want is, to write a value to input type=»file» . I have tried the code below but it’s not working.

2 Answers 2

You cannot, for fairly obvious security reasons.

If a webpage could specify a default value for a file input, then it could (for example) specify c:\place\where\finance\software\stores\accounts\by\default (and then use JavaScript to submit the form without the user having to do anything).

PHP aside, HTML doesn’t let you assign values to input type=»file» elements as a security measure. If HTML had this power, you could setup several of these fields and point each one to a windows file on the user’s computer. The result would be a victim submitting a form with no idea they were also submitting sensitive information. No JavaScript is required. The victim might submit such a form to log in or post a comment on a blog somewhere. Why wouldn’t the victim notice they are also submitting a file? CSS can style such elements offscreen using negative coordinates so its a lot like an input type=»hidden» , just in this case it would submitting a file instead.

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PHP File Upload

However, with ease comes danger, so always be careful when allowing file uploads!

Configure The «php.ini» File

First, ensure that PHP is configured to allow file uploads.

In your «php.ini» file, search for the file_uploads directive, and set it to On:

Create The HTML Form

Next, create an HTML form that allow users to choose the image file they want to upload:

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Some rules to follow for the HTML form above:

  • Make sure that the form uses method=»post»
  • The form also needs the following attribute: enctype=»multipart/form-data». It specifies which content-type to use when submitting the form

Without the requirements above, the file upload will not work.

  • The type=»file» attribute of the tag shows the input field as a file-select control, with a «Browse» button next to the input control

The form above sends data to a file called «upload.php», which we will create next.

Create The Upload File PHP Script

The «upload.php» file contains the code for uploading a file:

$target_dir = «uploads/»;
$target_file = $target_dir . basename($_FILES[«fileToUpload»][«name»]);
$uploadOk = 1;
$imageFileType = strtolower(pathinfo($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»] . «.»;
$uploadOk = 1;
> else echo «File is not an image.»;
$uploadOk = 0;
>
>
?>

  • $target_dir = «uploads/» — specifies the directory where the file is going to be placed
  • $target_file specifies the path of the file to be uploaded
  • $uploadOk=1 is not used yet (will be used later)
  • $imageFileType holds the file extension of the file (in lower case)
  • Next, check if the image file is an actual image or a fake image

Note: You will need to create a new directory called «uploads» in the directory where «upload.php» file resides. The uploaded files will be saved there.

Check if File Already Exists

Now we can add some restrictions.

First, we will check if the file already exists in the «uploads» folder. If it does, an error message is displayed, and $uploadOk is set to 0:

// Check if file already exists
if (file_exists($target_file)) echo «Sorry, file already exists.»;
$uploadOk = 0;
>

Limit File Size

The file input field in our HTML form above is named «fileToUpload».

Now, we want to check the size of the file. If the file is larger than 500KB, an error message is displayed, and $uploadOk is set to 0:

// Check file size
if ($_FILES[«fileToUpload»][«size»] > 500000) echo «Sorry, your file is too large.»;
$uploadOk = 0;
>

Limit File Type

The code below only allows users to upload JPG, JPEG, PNG, and GIF files. All other file types gives an error message before setting $uploadOk to 0:

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Complete Upload File PHP Script

The complete «upload.php» file now looks like this:

$target_dir = «uploads/»;
$target_file = $target_dir . basename($_FILES[«fileToUpload»][«name»]);
$uploadOk = 1;
$imageFileType = strtolower(pathinfo($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»] . «.»;
$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;
>

// 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 «. htmlspecialchars( basename( $_FILES[«fileToUpload»][«name»])). » has been uploaded.»;
> else echo «Sorry, there was an error uploading your file.»;
>
>
?>

Complete PHP Filesystem Reference

For a complete reference of filesystem functions, go to our complete PHP Filesystem Reference.

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Php form input file value

I think the way an array of attachments works is kind of cumbersome. Usually the PHP guys are right on the money, but this is just counter-intuitive. It should have been more like:

Array
(
[0] => Array
(
[name] => facepalm.jpg
[type] => image/jpeg
[tmp_name] => /tmp/phpn3FmFr
[error] => 0
[size] => 15476
)

Anyways, here is a fuller example than the sparce one in the documentation above:

foreach ( $_FILES [ «attachment» ][ «error» ] as $key => $error )
$tmp_name = $_FILES [ «attachment» ][ «tmp_name» ][ $key ];
if (! $tmp_name ) continue;

$name = basename ( $_FILES [ «attachment» ][ «name» ][ $key ]);

if ( $error == UPLOAD_ERR_OK )
if ( move_uploaded_file ( $tmp_name , «/tmp/» . $name ) )
$uploaded_array [] .= «Uploaded file ‘» . $name . «‘.
\n» ;
else
$errormsg .= «Could not move uploaded file ‘» . $tmp_name . «‘ to ‘» . $name . «‘
\n» ;
>
else $errormsg .= «Upload error. [» . $error . «] on file ‘» . $name . «‘
\n» ;
>
?>

Do not use Coreywelch or Daevid’s way, because their methods can handle only within two-dimensional structure. $_FILES can consist of any hierarchy, such as 3d or 4d structure.

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The following example form breaks their codes:

As the solution, you should use PSR-7 based zendframework/zend-diactoros.

use Psr \ Http \ Message \ UploadedFileInterface ;
use Zend \ Diactoros \ ServerRequestFactory ;

$request = ServerRequestFactory :: fromGlobals ();

if ( $request -> getMethod () !== ‘POST’ ) http_response_code ( 405 );
exit( ‘Use POST method.’ );
>

$uploaded_files = $request -> getUploadedFiles ();

if (
!isset( $uploaded_files [ ‘files’ ][ ‘x’ ][ ‘y’ ][ ‘z’ ]) ||
! $uploaded_files [ ‘files’ ][ ‘x’ ][ ‘y’ ][ ‘z’ ] instanceof UploadedFileInterface
) http_response_code ( 400 );
exit( ‘Invalid request body.’ );
>

$file = $uploaded_files [ ‘files’ ][ ‘x’ ][ ‘y’ ][ ‘z’ ];

if ( $file -> getError () !== UPLOAD_ERR_OK ) http_response_code ( 400 );
exit( ‘File uploading failed.’ );
>

$file -> moveTo ( ‘/path/to/new/file’ );

The documentation doesn’t have any details about how the HTML array feature formats the $_FILES array.

Array
(
[document] => Array
(
[name] => sample-file.doc
[type] => application/msword
[tmp_name] => /tmp/path/phpVGCDAJ
[error] => 0
[size] => 0
)
)

Multi-files with HTML array feature —

Array
(
[documents] => Array
(
[name] => Array
(
[0] => sample-file.doc
[1] => sample-file.doc
)

[type] => Array
(
[0] => application/msword
[1] => application/msword
) [tmp_name] => Array
(
[0] => /tmp/path/phpVGCDAJ
[1] => /tmp/path/phpVGCDAJ
)

The problem occurs when you have a form that uses both single file and HTML array feature. The array isn’t normalized and tends to make coding for it really sloppy. I have included a nice method to normalize the $_FILES array.

function normalize_files_array ( $files = [])

foreach( $files as $index => $file )

if (! is_array ( $file [ ‘name’ ])) $normalized_array [ $index ][] = $file ;
continue;
>

foreach( $file [ ‘name’ ] as $idx => $name ) $normalized_array [ $index ][ $idx ] = [
‘name’ => $name ,
‘type’ => $file [ ‘type’ ][ $idx ],
‘tmp_name’ => $file [ ‘tmp_name’ ][ $idx ],
‘error’ => $file [ ‘error’ ][ $idx ],
‘size’ => $file [ ‘size’ ][ $idx ]
];
>

?>

The following is the output from the above method.

Array
(
[document] => Array
(
[0] => Array
(
[name] => sample-file.doc
[type] => application/msword
[tmp_name] => /tmp/path/phpVGCDAJ
[error] => 0
[size] => 0
)

[documents] => Array
(
[0] => Array
(
[name] => sample-file.doc
[type] => application/msword
[tmp_name] => /tmp/path/phpVGCDAJ
[error] => 0
[size] => 0
) [1] => Array
(
[name] => sample-file.doc
[type] => application/msword
[tmp_name] => /tmp/path/phpVGCDAJ
[error] => 0
[size] => 0
)

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