How to set WebClient Content-Type Header?

Question

To conect to a third party service I need to make a Https Post. One of the requisites set is to sent a custom content type.

I'm using WebClient, but I can't find how to set it. I've tried making a new class and overriding the CreateRequest Method, but that make request crash.

Is there any way to do that without having to rewrite CopyHeadersTo method?

EDIT CopyHeaderTo is a method I've seen using .NET Reflector. It's invoked from GetWebRequest and sets all Request Headers, including Content-Type, from private properties.

score 47 · Answer 1 · answered Oct 20 '09 at 16:55

47

You could try adding to the Headers collection.

myWebClient.Headers.Add("Content-Type","application/xxx");

answered Oct 20 '09 at 16:55

Darin Dimitrov

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That throws a WebException, saying that Content-Type cannot be changed for current petition. – MaLKaV_eS Oct 21 '09 at 07:02
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Who throws this exception? Is it the server script you are posting to? I have tested the example provided in MSDN and it successfully set the Content-Type header to a custom value. – Darin Dimitrov Oct 21 '09 at 09:04
2

I had to do this: _client.Headers["Content-Type"] = "application/Json" Still not working correctly, but at least it compiles! Working in silverlight 5. – RaoulRubin Nov 17 '11 at 16:25
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Just wondering.. should you have called myWebClient.Headers.Remove("Content-Type") or maybe on a broader level called myWebClient.Headers.Clear() first before setting/Adding Content-Type? – Dinesh Rajan Feb 14 '14 at 15:57

score 15 · Answer 2 · edited Dec 10 '19 at 06:24

15

webclient.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";

edited Dec 10 '19 at 06:24

Uwe Keim

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answered Jul 22 '15 at 09:15

V K

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score 4 · Accepted Answer · edited Mar 16 '18 at 17:47

4

Well, I just missed Request.ContentType property. If GetWebRequest method is overridden, setting ContentType to whatever value desired does it.

Still, connection to third party is not working. Go figure.

edited Mar 16 '18 at 17:47

JYelton

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answered Oct 21 '09 at 08:19

MaLKaV_eS

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score 3 · Answer 4 · answered Feb 06 '17 at 06:30

I encounter this too. And found that you must use Client Http, otherwise Browser Http will block change of Content-Type for security reason. This MSDN link explain that.

WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp);
WebRequest.RegisterPrefix("https://", WebRequestCreator.ClientHttp);
client.Headers["Content-Type"] = "application/json";

How to set WebClient Content-Type Header?

4 Answers4

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