jQuery ajax fileupload [关闭]

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            <div class="grid--cell mb0 mt8">Closed <span title="2013-03-04 12:44:04Z" class="relativetime">7 years ago</span>.</div>
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I need an asynchronous file uploader. No, i am not looking for a plugin. I am just looking for a simple jquery+AJAX uploader that will upload the file asynchronously. I have checked Google but haven't found anything useful.

Here is my html:

    <form method="post" enctype="multipart/form-data" "> 

File Name:<input type="text" name="name"/> <br/><br/>

Browse: <input type="file" name="file"/> <br/><br/> 

<input type="submit" id='button' Value="Upload the video file" name="submit"/>

 </form>

my php code:

<?php
if(isset($_POST["submit"]))
{
$filename=$_POST["name"];
$ext = pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION);
$size=$_FILES["file"]["size"];
$size=$size/1000000;
$size=round($size, 2);
$size.="MB";
$namewithext=$filename." (".$size.")".".".$ext;
  if ($_FILES["file"]["error"] > 0)
    {
    echo "Return Code: " . $_FILES["file"]["error"] . "<br>";
    }
  else
    {
    if (file_exists("file/" . $_FILES["file"]["name"]))
      {
      echo "<script> alert('".$_FILES["file"]["name"] . " already exists. "."');</script>";
      }
    else
      {

      move_uploaded_file($_FILES["file"]["tmp_name"],
      "file/" . $namewithext);
      echo "<script> alert('"."success"."');</script>";


      }
    }
}
  else
  {

  }
?>

I have no experience with jquery. Thanks so much!

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