ASP.Net (VB) How to redirect to a new page one a file exists

Hi,

I have a webpage that creates a file, and then when an external process notices that file, a second file is created automatically.

Now I want the webpage to be able to poll for that file, and when it exists, redirect to a new page.

How do I do this?

Richard
LVL 1
rpmAsked:
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Walter PadrónCommented:
Richard, is not clear for me,

do you want to check for the second file  every time you load the web page (the check is on the server)
or
upload the file and then wait and poll the server until the second file was created (the check is on the client)?

Best regards
0
rpmAuthor Commented:
I think the second case is what I need.

The webpage will create file1, then file2 will be automatically created on the server (not by the webpage!)

Once file2 exists on the server, I want to redirect to another page.

Richard
0
Walter PadrónCommented:
I need to setup a project to test the solution  but you should try something like this

$.ajax({
    url:'http://www.example.com/somefile.ext',
    type:'HEAD',
    error: function()
    {
        //file not exists. Set a delay and try again
    },
    success: function()
    {
        //Do whatever action you need
    }
});

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Walter PadrónCommented:
This is what you need using Ajax polling
http://www.binaryintellect.net/articles/fd949e1f-dab4-4a20-938b-1e84773136a2.aspx

Best regards
0
rpmAuthor Commented:
That looks hopeful, but I have a couple of questions:

1) Where does the $.ajax code section go? Is it within the <head>?

2) Knowing virtually nothing about ajax, how do I set the resulting action to be a page redirection, to a new page if the file is present?

Thanks,

Richard
0
Walter PadrónCommented:
1 - The javascript code can be anywhere, for faster page load put it before the end of the body section
  <script type="text/javascript">
     // code here
  </script>
</body>

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2- use this code in your javascript
 window.location="http://www.newpage.com";

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Best regards
0

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