YA: File Upload Processing 20130626091720AAGnj4f

<?php

// Yahoo Answers' Question: http://answers.yahoo.com/question/index?qid=20130626091720AAGnj4f

/***   Upload Error Messages (Debug and User modes)   ***/
$DebugUploadErrors = array(
    1 => 'The uploaded file exceeds the Server\'s Maximum Allowable File Size',
    2 => 'The uploaded file exceeds the Form\'s Maximum Allowable File Size.', // Set by the form's MAX_FILE_SIZE property
    3 => 'The uploaded file was only partially uploaded, then interrupted or the connection was dropped.',
    4 => 'No file was uploaded.',
    6 => 'Missing a temporary folder. The server requires a temporary folder for file uploads.', // Internal Operations Error
    7 => 'Failed to write file to disk.', // Internal Server Error
    8 => 'A PHP extension stopped the file upload.' // PHP Extension Library stopped the upload.
);
$UserUploadErrors = array(
    1 => 'The selected file exceeds the allowable Server file size. Please select an alternate file.',
    2 => 'The selected file exceeds the allowable Upload file size. Please select an alternate file.',
    3 => 'Upload connection was interuppted or dropped. Please try again.',
    4 => 'Please select a file to upload.',
    6 => 'Internal Server Error (#606). Please inform site Admin.', // Internal Operations Error
    7 => 'Internal Server Error (#707). Please inform site Admin and please try again.', // Internal Server Error
    8 => 'Internal Server Error (#808). Please inform site Admin.' // PHP Extension Library stopped the upload.
);
// Change for whatever is appropriate. You can place this change in if statements checking for admin or debug mode.
$UploadErrors = $DebugUploadErrors; // or $UserUploadErrors



/***   Variables   ***/
$maxFilesize = 2000000;
$allowedExts = Array('gif', 'jpg', 'jpeg', 'mp4', 'png');
$errors = Array(); // Will hold the error messages
$uploadDir = 'useruploads/';


if( isset($_FILE['file']) ){
    $f = $_FILE['file'];
    $newFile = rtrim($uploadDir, '/') . '/' . $f['name'];
    $ext = pathinfo($f['name'], PATHINFO_EXTENSION);

    // Error Checking
    if( !in_array($ext, $allowedExts) ){ // Filetype
        $errors[] = 'Filetype is not supported. Please select a supported file type (' . implode(', ', $allowedExts) . ').';
    }
    if( (int)$f['size'] > $maxFilesize ){ // Filesize
        $errors[] = 'The selected file is too large for this process. Please select a file smaller than ' . $maxFilesize . ' bytes.';
    }
    if( $f['error'] !== UPLOAD_ERROR_OK){ // Upload Error Status (UPLOAD_ERR_OK -> PHP Constant for the value of a successfull upload)
        $errors[] = $UploadErrors[(int)$f['error']];
    }

    // If Errors display, otherwise move uploaded file.
    if( isset($errors[0]) ){ // Errors Exist
        echo 'The following errors were found while trying to process your upload: <br />';
        echo '<ul><li>' . implode('</li><li>', $errors) . '</li></ul><br />';
    }else if( move_uploaded_file($f['tmp_name'], $newFile)){
        echo 'The file "' . $f['name'] . '" was uploaded successfully.<br />';
    }else{
        echo 'Moving of uploaded file failed. Please check folder and script permissions.<br />';
    }
}else{
    // Normally even if the user doesn't select a file, then the browser still sends the empty variable,
    // and the server sets the upload error to '4' (no file was uploaded). Although some versions of iOS and
    // versions of Safari Browser do not send the empty file upload variable, so the server is unaware there
    // was suppose to be a file upload, so it doesn't populate the $_FILES superglobal, let alone with the
    // error. So this error message can be reached in a couple of different scenarios, but mainly by users
    // who simply browsed to the page, without submitting the form.
    echo 'UPLOAD ERROR: Please select a file to upload.';
}