Exception when download image using WebRequest.GetResponse - How?

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Hi all,
I am programing a module which download images from internet.
I am using code as below:

WebRequest wr = WebRequest.Create(url);
WebResponse ws = wr.GetResponse(); // => throw exception
Stream dataStream = ws.GetResponseStream();

But, there are some exception that I dont know how to resolve:

Url 1: http://dtgroup.com.vn/uploads/news/2011_08/ipd1311237144.gif
=> throw exception: The server committed a protocol violation. Section=ResponseHeader Detail=Header name is invalid

Url 2: http://cocdoc.fpt.edu.vn/sites/default/files/imagecache/318x191/anhtin/2_3.JPG
=> throw exception: The remote server returned an error: (403) Forbidden.

Infact, both url work on Firefox/Chrome, but my program cant download them.

Could you please show me some guides.
Thanks so much.
TuanNM

Posted 9-Apr-12 16:03pm

TuanNGUYEN

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Sergey Alexandrovich Kryukov 9-Apr-12 22:33pm

I see... reproduced the problem. Up-voted the question.
--SA

2 solutions

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Bernhard Hiller · Answer 1 · 2012-04-09T23:11:00

Solution 1

Some servers check for a valid "referer". Since you can access the images directly with Firefox, that is excluded.
Another idea is the "user agent". Try to set it in your application to Firefox (find out the correct wording!), perhaps that helps.

Posted 9-Apr-12 23:11pm

Bernhard Hiller

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TuanNGUYEN 11-Apr-12 0:04am

Thank so much,
The Url 2 work with "User Agent", but the Url 1 doesn't work.
I've tried some Referers, but the Url 1 doesn't work. Now I'm reading more about "Referer".
If you have experiences on setting Referer, could you please give me some guides.

Nilesh V Raut · Answer 2 · 2015-11-01T23:10:00

Solution 2

Try putting this code in your app or web.config file :

XML

<system.net>
    <settings>
        <httpWebRequest useUnsafeHeaderParsing="true" />
    </settings>
</system.net>

Posted 1-Nov-15 23:10pm

Nilesh V Raut