使用FTP和php上传文件

I can't Upload the file using php because i can't send the path i got from the html file to the function FTP_PUT because it only takes string "test.txt"

How Can i send the Path to this function

PHP FILE

$file = $_POST["file"];

// upload file
if (ftp_put($ftp_conn, $file, $file, FTP_BINARY))
  {
  echo "Successfully uploaded $file.";
  }
else
  {
  echo "Error uploading $file.";
  }

// close connection
ftp_close($ftp_conn);

HTML FILE

<div class="container">
 
          <div class="row">
            <div class="col-lg-12">
               <form class="well" action="Upload.php" method="post" >
                  <div class="form-group">
                    <label for="file">Select a file to upload</label>
                    <input type="file" name="file" id="file">

                   <!-- <p class="help-block">Only jpg,jpeg,png and gif file with maximum size of 1 MB is allowed.</p> -->
                  </div>
                  <input type="submit" class="btn btn-lg btn-primary" value="Upload">
                </form>
            </div>
          </div>
    </div>