176
votes

I want to implement a simple file upload in my intranet-page, with the smallest setup possible.

This is my HTML part:

<input id="sortpicture" type="file" name="sortpic" />
<button id="upload">Upload</button>

and this is my JS jquery script:

$("#upload").on("click", function() {
    var file_data = $("#sortpicture").prop("files")[0];   
    var form_data = new FormData();
    form_data.append("file", file_data);
    alert(form_data);
    $.ajax({
        url: "/uploads",
        dataType: 'script',
        cache: false,
        contentType: false,
        processData: false,
        data: form_data,                         
        type: 'post',
        success: function(){
            alert("works"); 
        }
    });
});

There is a folder named "uploads" in the root directory of the website, with change permissions for "users" and "IIS_users".

When I select a file with the file-form and press the upload button, the first alert returns "[object FormData]". the second alert doesn't get called and the"uploads" folder is empty too!?

Can someone help my finding out whats wrong?

Also the next step should be, to rename the file with a server side generated name. Maybe someone can give me a solution for this, too.

5
Everything works for me, maybe it's your PHP code?Korikulum
there is nothing else "connected" with this form. what do you mean with my php code?user2355509
What I mean is, your code works, maybe the problem is in your server side code.Korikulum
Are you getting an 500 error code upon executing the AJAX script? That would indicate that it is a server side error. Also: make sure that while debugging, you output the PHP file's response to the console. That way, if your PHP code throws an error, you know what's going on.Diederik

5 Answers

304
votes

You need a script that runs on the server to move the file to the uploads directory. The jQuery ajax method (running in the browser) sends the form data to the server, then a script on the server handles the upload. Here's an example using PHP.

Your HTML is fine, but update your JS jQuery script to look like this:

$('#upload').on('click', function() {
    var file_data = $('#sortpicture').prop('files')[0];   
    var form_data = new FormData();                  
    form_data.append('file', file_data);
    alert(form_data);                             
    $.ajax({
        url: 'upload.php', // <-- point to server-side PHP script 
        dataType: 'text',  // <-- what to expect back from the PHP script, if anything
        cache: false,
        contentType: false,
        processData: false,
        data: form_data,                         
        type: 'post',
        success: function(php_script_response){
            alert(php_script_response); // <-- display response from the PHP script, if any
        }
     });
});

And now for the server-side script, using PHP in this case.

upload.php: a PHP script that runs on the server and directs the file to the uploads directory:

<?php

    if ( 0 < $_FILES['file']['error'] ) {
        echo 'Error: ' . $_FILES['file']['error'] . '<br>';
    }
    else {
        move_uploaded_file($_FILES['file']['tmp_name'], 'uploads/' . $_FILES['file']['name']);
    }

?>

Also, a couple things about the destination directory:

  1. Make sure you have the correct server path, i.e., starting at the PHP script location what is the path to the uploads directory, and
  2. Make sure it's writeable.

And a little bit about the PHP function move_uploaded_file, used in the upload.php script:

move_uploaded_file(

    // this is where the file is temporarily stored on the server when uploaded
    // do not change this
    $_FILES['file']['tmp_name'],

    // this is where you want to put the file and what you want to name it
    // in this case we are putting in a directory called "uploads"
    // and giving it the original filename
    'uploads/' . $_FILES['file']['name']
);

$_FILES['file']['name'] is the name of the file as it is uploaded. You don't have to use that. You can give the file any name (server filesystem compatible) you want:

move_uploaded_file(
    $_FILES['file']['tmp_name'],
    'uploads/my_new_filename.whatever'
);

And finally, be aware of your PHP upload_max_filesize AND post_max_size configuration values, and be sure your test files do not exceed either. Here's some help how you check PHP configuration and how you set max filesize and post settings.

6
votes
**1. index.php**
<body>
    <span id="msg" style="color:red"></span><br/>
    <input type="file" id="photo"><br/>
  <script type="text/javascript" src="jquery-3.2.1.min.js"></script>
  <script type="text/javascript">
    $(document).ready(function(){
      $(document).on('change','#photo',function(){
        var property = document.getElementById('photo').files[0];
        var image_name = property.name;
        var image_extension = image_name.split('.').pop().toLowerCase();

        if(jQuery.inArray(image_extension,['gif','jpg','jpeg','']) == -1){
          alert("Invalid image file");
        }

        var form_data = new FormData();
        form_data.append("file",property);
        $.ajax({
          url:'upload.php',
          method:'POST',
          data:form_data,
          contentType:false,
          cache:false,
          processData:false,
          beforeSend:function(){
            $('#msg').html('Loading......');
          },
          success:function(data){
            console.log(data);
            $('#msg').html(data);
          }
        });
      });
    });
  </script>
</body>

**2.upload.php**
<?php
if($_FILES['file']['name'] != ''){
    $test = explode('.', $_FILES['file']['name']);
    $extension = end($test);    
    $name = rand(100,999).'.'.$extension;

    $location = 'uploads/'.$name;
    move_uploaded_file($_FILES['file']['tmp_name'], $location);

    echo '<img src="'.$location.'" height="100" width="100" />';
}
3
votes

Use pure js

async function saveFile() 
{
    let formData = new FormData();           
    formData.append("file", sortpicture.files[0]);
    await fetch('/uploads', {method: "POST", body: formData});    
    alert('works');
}
<input id="sortpicture" type="file" name="sortpic" />
<button id="upload" onclick="saveFile()">Upload</button>
<br>Before click upload look on chrome>console>network (in this snipped we will see 404)

The filename is automatically included to request and server can read it, the 'content-type' is automatically set to 'multipart/form-data'. Here is more developed example with error handling and additional json sending

async function saveFile(inp) 
{
    let user = { name:'john', age:34 };
    let formData = new FormData();
    let photo = inp.files[0];      
         
    formData.append("photo", photo);
    formData.append("user", JSON.stringify(user));  
    
    try {
       let r = await fetch('/upload/image', {method: "POST", body: formData}); 
       console.log('HTTP response code:',r.status); 
       alert('success');
    } catch(e) {
       console.log('Huston we have problem...:', e);
    }
    
}
<input type="file" onchange="saveFile(this)" >
<br><br>
Before selecting the file Open chrome console > network tab to see the request details.
<br><br>
<small>Because in this example we send request to https://stacksnippets.net/upload/image the response code will be 404 ofcourse...</small>
2
votes
var formData = new FormData($("#YOUR_FORM_ID")[0]);
$.ajax({
    url: "upload.php",
    type: "POST",
    data : formData,
    processData: false,
    contentType: false,
    beforeSend: function() {

    },
    success: function(data){




    },
    error: function(xhr, ajaxOptions, thrownError) {
       console.log(thrownError + "\r\n" + xhr.statusText + "\r\n" + xhr.responseText);
    }
});
0
votes

and this is the php file to receive the uplaoded files

<?
$data = array();
    //check with your logic
    if (isset($_FILES)) {
        $error = false;
        $files = array();

        $uploaddir = $target_dir;
        foreach ($_FILES as $file) {
            if (move_uploaded_file($file['tmp_name'], $uploaddir . basename( $file['name']))) {
                $files[] = $uploaddir . $file['name'];
            } else {
                $error = true;
            }
        }
        $data = ($error) ? array('error' => 'There was an error uploading your files') : array('files' => $files);
    } else {
        $data = array('success' => 'NO FILES ARE SENT','formData' => $_REQUEST);
    }

    echo json_encode($data);
?>