PHP使用jquery和PHP在用户请求上重命名或替换上传的文件

Question

I am developing a PHP application in which I have to upload multiple files on the server, what I want is that when a user uploads multiple files the system should check if any of the files already exists, if yes then it should ask the user whether to rename the file or replace the older file,if user selects the rename option it should rename the file and if the user asks to replace the file it should do accordingly.

Untill Now I am using the following Code to upload the files:

<?php
if(isset($_FILES['files'])){
$errors= array();
     foreach($_FILES['files']['tmp_name'] as $key => $tmp_name ){
    $file_name = $_FILES['files']['name'][$key];
$file_size =$_FILES['files']['size'][$key];
$file_tmp =$_FILES['files']['tmp_name'][$key];
$file_type=$_FILES['files']['type'][$key];  
if($file_size > 2097152){
    $errors[]='File size must be less than 2 MB';
}       
 //   $query="INSERT into upload_data (`USER_ID`,`FILE_NAME`,`FILE_SIZE`,`FILE_TYPE`) VALUES('$user_id','$file_name','$file_size','$file_type'); ";
$desired_dir="../reztrictedfolder/dir1/";
if(empty($errors)==true){
    if(is_dir($desired_dir)==false){
        mkdir("$desired_dir", 0700);        // Create directory if it does not exist
    }
    if(file_exists("$desired_dir/".$file_name)==false){
        move_uploaded_file($file_tmp,"../reztrictedfolder/dir1/".$file_name);
    }else{                                  //rename the file if another one exist

         //rename($file_tmp,$new_dir) ; 
        list($txt,$ext) = explode(".", $file_name);

        $actual_image_name = time().substr(str_replace(" ", "_", $txt),     5).".".$ext;
     $new_dir="../reztrictedfolder/dir1/".$actual_image_name."_copy";
        move_uploaded_file($file_tmp,$new_dir);              
    }
  //  mysql_query($query);          
}else{
       // print_r($errors);
}

But it only checks if the file already exists and rename it, but I want to let the user know that file already exists and if he wants to rename the file or replace the existing file..?

Answer 1

If you use AJAX so you sent from PHP response to JavaScript, which contains a list of file. I've use a function json_encode as parameters list of file. In javascript use JSON.parse()

HTML Section

<form id="upload" action="upload.php" method="POST" enctype="multipart/form-data">

<fieldset>
<input type="hidden" id="MAX_FILE_SIZE" name="MAX_FILE_SIZE" value="300000" />
<div>
    <label for="fileselect">Files to upload:</label>
    <input type="file" id="fileselect" name="fileselect[]" multiple="multiple" />
    <div id="filedrag">or drop files here</div>
</div>

<div id="submitbutton">
    <button type="submit">Upload Files</button>
</div>

</fieldset>

</form>

JavaScript

function FileSelectHandler(e) {
    var files = e.target.files || e.dataTransfer.files;

    for (var i = 0, f; f = files[i]; i++) {
        UploadFile(f);
    }

}

function ResponseParse(data) {
     if (typeof data === "object") {
         for (var i = 0, lng = data.files.length; i < lng; i++) console.log(data.files[i]);
     }
}

function UploadFile(file) {
    var xhr = new XMLHttpRequest();
    // for example only jpeg file allowed
    if (xhr.upload && file.type == "image/jpeg" && file.size <= $id("MAX_FILE_SIZE").value) {
        xhr.open("POST", $id("upload").action, true);
        xhr.setRequestHeader("X_FILENAME", file.name);
        xhr.onreadystatechange = function() {//Call a function when the state changes.
            if(http.readyState == 4 && http.status == 200) {
                // Response from server
                var data = JSON.parse(http.responseText);
                ResponseParse(data);
            }
        }
        xhr.send(file);

    }

}

PHP

<?php
$fn = (isset($_SERVER['HTTP_X_FILENAME']) ? $_SERVER['HTTP_X_FILENAME'] : false);
if ($fn) {
    file_put_contents(
        'uploads/' . $fn,
        file_get_contents('php://input')
    );
    exit;

}
else {
    $files = $_FILES['fileselect'];
    $uploaded['files'] = array();

    foreach ($files['error'] as $id => $err) {
        if ($err == UPLOAD_ERR_OK) {
            $fn = $files['name'][$id];
            $uploaded['files'][] = $files['name'][$id];
            move_uploaded_file(
                $files['tmp_name'][$id],
                'uploads/' . $fn
            );
        }
    }
header('Content-type: application/json; charset=utf-8');
echo json_encode($uploaded);
}

This example working with XMLHttpRequest2. List of supported browser http://caniuse.com/#feat=xhr2. If you support old browser, you must old form-style upload or iframe upload idally by jquery, like this https://blueimp.github.io/jQuery-File-Upload/