Possible to generate a file in javascript and prompt the user to download?

Question

Is it possible to generate a file in javascript and then prompt the user to download ?

What we would really like to do is the following : we want to make a small html form where an user can edit values in a table, and we would like to be able to generate a csv file from the form and prompt the user to save it on his hard drive. Is it possible in pure javascript ? If not, are there any workarounds ?

Note : I know I could solve this by a round-trip to a server, sending the form and getting a csv file back, but the trick here is that there is no server, the html form will just be generated on a hard drive.

score 1 · Answer 1 · answered Feb 01 '13 at 19:35

If you don't mind using flash, I suggest you use Downloadify. You host downloadify.swf that you will serve with your javascript content generating code.

It is easy to integrate. Here is a cut&paste from the provided sample web site :

<script type="text/javascript">
  Downloadify.create('downloadify',{
    filename: function(){
      return document.getElementById('filename').value;
    },
    data: function(){ 
      return document.getElementById('data').value;
    },
    onComplete: function(){ 
      alert('Your File Has Been Saved!'); 
    },
    onCancel: function(){ 
      alert('You have cancelled the saving of this file.');
    },
    onError: function(){ 
      alert('You must put something in the File Contents or there will be nothing to save!'); 
    },
    transparent: false,
    swf: 'media/downloadify.swf',
    downloadImage: 'images/download.png',
    width: 100,
    height: 30,
    transparent: true,
    append: false
  });
</script>

score 1 · Accepted Answer · answered Oct 29 '09 at 10:21

1

Without a server to download from, you cant get them to download the data like normal.

You could output the csv data to a new browser window and the user could then save this.

answered Oct 29 '09 at 10:21

Mongus Pong

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score 0 · Answer 3 · answered Oct 29 '09 at 10:35

In pure javascript, no.

You'd need a server side script to generate the file and save it temporarily/ in memory, and then present a force-download dialogue to the user.

Suggest you take Fungus' route and use javascript to write it to a browser window, then instructing the user how to save it (Copy > Paste ... etc).

Cheers, Sean

Possible to generate a file in javascript and prompt the user to download?

3 Answers3