Browser compatibility Issue : Upload and Preview using Paperclip

Rails
1

Hi,

I am using uploading(img) process in my app using paperclip. My new
requirement is to preview before submitting.

My new requirement works only in FIREFOX not in IE,CHROME,SAFARI. My
code looks this.

<%= form.file_field :image, :onchange=> “setImage(this);” %>

function setImage(file) {
if(document.all)
document.getElementById(‘prevImage’).src = file.value;
else
document.getElementById(‘prevImage’).src =
file.files.item(0).getAsDataURL();

    if(document.getElementById('prevImage').src.length > 0)
        document.getElementById('prevImage').style.display =

‘block’;
}

Thanks in Advance
Mathew

2

You basically need to preview an before it has been
submitted? This sounds more like a JavaScript question than a Rails
question.

3

Tim S. wrote in post #1022142:

You basically need to preview an before it has been
submitted? This sounds more like a JavaScript question than a Rails
question.

This issue corresponds to javascript+css concept only.

4

Colin L. wrote in post #1022182:

On 15 September 2011 14:58, Mathew V. [email protected] wrote:

Tim S. wrote in post #1022142:

You basically need to preview an before it has been
submitted? This sounds more like a JavaScript question than a Rails
question.

This issue corresponds to javascript+css concept only.

In that case a Ruby on Rails mailing list may not be the best place to
get help.

But in your situation the first thing I would try is to run it in
firebug in firefox to check for errors. Also paste the complete page
html into the w3c html validator to check for valid html. Differences
between browsers is often caused by invalid html.

Colin

–
gplus.to/clanlaw

Thanks Colin for your idea…
I have checked my HTML that has some errors.
But now i changed. It is valid now but the issue remains the same.

5

On 16 September 2011 07:39, Mathew V. [email protected] wrote:

get help.

Thanks Colin for your idea…
I have checked my HTML that has some errors.
But now i changed. It is valid now but the issue remains the same.

And running it with firebug in firefox?

Colin

–
gplus.to/clanlaw

6

Colin L. wrote in post #1022271:

On 16 September 2011 07:39, Mathew V. [email protected] wrote:

get help.

And running it with firebug in firefox?

I didnt see any errors in firebug.
I have tried another script right now. it is working in
ubuntu(firefox,chrome)…
I have to check the windows os and will update it.

thanks once again.

7

On 15 September 2011 14:58, Mathew V. [email protected] wrote:

Tim S. wrote in post #1022142:

You basically need to preview an before it has been
submitted? This sounds more like a JavaScript question than a Rails
question.

This issue corresponds to javascript+css concept only.

In that case a Ruby on Rails mailing list may not be the best place to
get help.

But in your situation the first thing I would try is to run it in
firebug in firefox to check for errors. Also paste the complete page
html into the w3c html validator to check for valid html. Differences
between browsers is often caused by invalid html.

Colin

–
gplus.to/clanlaw

8

On Sep 15, 6:38am, Mathew V. [email protected] wrote:

function setImage(file) {
if(document.all)
document.getElementById(‘prevImage’).src = file.value;
else
document.getElementById(‘prevImage’).src =
file.files.item(0).getAsDataURL();

To be honest, I’m surprised this works at all - file fields are
notoriously resistant to being read via JS, for security reasons. If
this is a critical part of your application, you may need to go to an
alternative method (Flash, for instance) to have it work reliably
across browsers and security settings.

–Matt J.