How can I convince IE to simply display application/json rather than offer to download it?

Question

While debugging jQuery apps that use AJAX, I often have the need to see the json that is being returned by the service to the browser. So I'll drop the URL for the JSON data into the address bar.

This is nice with ASPNET because in the event of a coding error, I can see the ASPNET diagostic in the browser:

But when the server-side code works correctly and actually returns JSON, IE prompts me to download it, so I can't see the response.

Can I get IE to NOT do that, in other words, to just display it as if it were plain text?

I know I could do this if I set the Content-Type header to be text/plain.

But this is specifically an the context of an ASPNET MVC app, which sets the response automagically when I use JsonResult on one of my action methods. Also I kinda want to keep the appropriate content-type, and not change it just to support debugging efforts.

Santalaceous

Firefox 3/4 also does this, if you have a machine that hasn't been updated. – Schoening

I like the usage of "convince"!! – Ance

Answer 1

I found the answer.

You can configure IE8 to display application/json in the browser window by updating the registry. There's no need for an external tool. I haven't tested this broadly, but it works with IE8 on Vista.

To use this, remember, all the usual caveats about updating the registry apply. Stop IE. Then, cut and paste the following into a file, by the name of json-ie.reg.

Windows Registry Editor Version 5.00
;
; Tell IE to open JSON documents in the browser.  
; 25336920-03F9-11cf-8FD0-00AA00686F13 is the CLSID for the "Browse in place" .
;  

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/json]
"CLSID"="{25336920-03F9-11cf-8FD0-00AA00686F13}"
"Encoding"=hex:08,00,00,00

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\text/json]
"CLSID"="{25336920-03F9-11cf-8FD0-00AA00686F13}"
"Encoding"=hex:08,00,00,00

Then double-click the .reg file. Restart IE. The new behavior you get when tickling a URL that returns a doc with Content-Type: application/json or Content-Type: text/json is like this:

What it does, why it works:

The 25336920-03F9-11cf-8FD0-00AA00686F13 is the CLSID for the "Browse in place" action. Basically this registry entry is telling IE that for docs that have a mime type of application/json, just view it in place. This won't affect any application/json documents downloaded via <script> tags, or via XHR, and so on.

The CLSID and Encoding keys get the same values used for image/gif, image/jpeg, and text/html.

This hint came from this site, and from Microsoft's article Handling MIME Types in Internet Explorer .

---

In FF, you don't need an external add-on either. You can just use the view-source: pseudo-protocol. Enter a URL like this into the address bar:

view-source:http://myserver/MyUrl/That/emits/Application/json

This pseudo-protocol used to be supported in IE, also, until WinXP-sp2, when Microsoft disabled it for security reasons.

Santalaceous

I tried this one on XP but didn't work. @SkySanders solution work. Nevertheless, +1 :) – Febrifugal

If you want to skip creating the registry file, here's a one-liner you can paste into a powershell window: reg add "HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/json" /t REG_SZ /d "{25336920-03F9-11cf-8FD0-00AA00686F13}"; reg add "HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/json" /v Encoding /t REG_DWORD /d 0x08000000 – Galbraith

Brilliant, brilliant, brilliant! At last, my IE 8 can behave like a grown-up browser, like Chrome, and display the results of a JSON web call. Many thanks for this .reg script... worked a treat. Brilliant! – Towpath

Is this technique known to work (or NOT work) on IE 9? It's not working for me yet, am I wasting my time trying? – Sellma

Thanks @Cheeso. NOTE: some web APIs return JSON with the Content-type text/javascript to also view these in-place in IE (including IE9) use the .reg script above but add a third section for text/javascript. – Sellma

This cannot be the solution. This would mean I would have to ask the largest part of the world (e.g. IE users) to run some script to fix the registry???? – Flammable

@nathanvda, there is no need to ask the largest part of the world anything. Showing JSON in the browser is something a developer of an AJAX page would want to do. It's completely unnecessary to display JSON in the browser for regular users. – Santalaceous

My bad, I misread the question: i had a form which returned json which failed with the same error. – Flammable

I made the fatal mistake of allowing a friend to borrow my box and he ran this fix. Does anyone know what the original settings are so that I might reverse them? – Len

@Len just delete the application/json and text/json keys entirely, they do not exist by default. – Nidanidaros

Works fine with IE10/Windows 7 (+1) – Chaudfroid

Not sure why this response has received 80 points?! What about a public facing website visited by thousands or million users running IE? Would you tell each user to go and update their registry so IE displays JSON for them?! There must be a better solution! – Eldin

@Mosh, this was mentioned by nathanvda above, the solution isn't so that users of the website can view the JSON, it's simply for a debugging purpose. Read the entire question. – Quickel

If you don't have admin rights, then you can replace HKEY_CLASSES_ROOT\MIME with HKEY_CURRENT_USER\Software\Classes\MIME. – Decare

This is still working in IE11 on win 8.1. Didn't even need to restart the browser. In my case I needed the text/json key. – Grey

OH OK, I'll just ask the whole internet to do this... smh – Hammons

Answer 2

I had a similar problem. I was using the "$. GetJSON" jQuery and everything worked perfectly in Firefox and Chrome.

But it did not work in IE. So I tried to directly access the URL of json, but in IE it asked if I wanted to download the file.

After much searching I saw that there must be a header in the result with a content-type, in my case, the content-type was:

header("Content-type: text/html; charset=iso-8859-1");

But when the page that made the request receives this json, in IE, you have to be specified SAME CONTENT-TYPE, in my case was:

$.getJSON (
"<? site_url php echo (" ajax / tipoMenu ")?>"
{contentType: 'text / html; charset = utf-8'},
function (result) {

hugs

Boffin

This worked for me, no messing with registry required, just change the response header too "text/html". – Papyraceous

How does this work in IE7 when making an Ajax call and receives json as a result? I'm not using getJSON but rather a .ajax call. I've used that content type in response and header and it doesnt help at all. Neither did using json2.js. Does anyone have successful implementations of this that work in ie7? IE7 represents more than 30% of our users. Sad but true, and a reg key change isn't an option. Telling a million governmment users to just run a reg hack won't fly. – Kenney

I know this is an old question, but it is being repeated, so here's the answer: The original question pertains to DEVELOPERS who are debugging the retrieval of JSON. Modifying the reg is suggested as a step to help those developers. Modyfing the registry is not recommended or suggested for general users. Also: there is NEVER a need for regular users (= a million government users) to view JSON in the browser. – Santalaceous

Just use text/plain; charset=UTF-8. No need to text/html. – Omegaomelet

Answer 3

Above solution was missing thing, and below code should work in every situation:

Windows Registry Editor Version 5.00
;
; Tell IE to open JSON documents in the browser.  
; 25336920-03F9-11cf-8FD0-00AA00686F13 is the CLSID for the "Browse in place" .
;  

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/json]
"CLSID"="{25336920-03F9-11cf-8FD0-00AA00686F13}"
"Encoding"=hex:08,00,00,00

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/x-json]
"CLSID"="{25336920-03F9-11cf-8FD0-00AA00686F13}"
"Encoding"=hex:08,00,00,00

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\text/json]
"CLSID"="{25336920-03F9-11cf-8FD0-00AA00686F13}"
"Encoding"=hex:08,00,00,00

Just save it file json.reg, and run to modify your registry.

Wareing

My work computer is locked down. If you need to command line add these, see this answer. #13810356 Thanks OP. I see json in IE........yay! – Adjustment

Answer 4

Changing IE's JSON mime-type settings will effect the way IE treats all JSON responses.

Changing the mime-type header to text/html will effectively tell any browser that the JSON response you are returning is not JSON but plain text.

Neither options are preferable.

Instead you would want to use a plugin or tool like the above mentioned Fiddler or any other network traffic inspector proxy where you can choose each time how to process the JSON response.

Gaultiero

text/html does not tell the browser that the response is plain text, but HTML. If you do decide you want plain text, use text/plain. Otherwise you can end up with some interesting XSS vulnerabilities. – Toxinantitoxin

Answer 5

If you are okay with just having IE open the JSON into a notepad, you can change your system's default program for .json files to Notepad.

To do this, create or find a .json file, right mouse click, and select "Open With" or "Choose Default Program."

This might come in handy if you by chance want to use Internet Explorer but your IT company wont let you edit your registry. Otherwise, I recommend the above answers.

Farrell

Answer 6

I use Fiddler with JSONViewer plugin to inspect JSON. I don't think it is possible to make IE behave without fiddling with registry perhaps. Here's some information.

Apatetic

Answer 7

FireFox + FireBug is very good for this purpose. For IE there's a developer toolbar which I've never used and intend to use so I cannot provide much feedback.

Quicken

yep, I know about the FF plugin that allows the display of application/json as regular text. I specifically wanna know about IE, though. – Santalaceous

There's a developer toolbar for IE. By the way here's a nice comparison of different tools for developers : elegantcode.com/2009/05/18/… – Quicken

Answer 8

I just had the same issue with an XMLHttpRequest. The site functions flawlessly in Chrome and FF, and in dozens upon dozens of Internet Explorer browsers in production. This ONE machine (the one our company is setting up to be a demo machine, of course) decided that it was going to prompt to save the json response to an ajax request.

The accepted regedit solution below fixed it. Thanks.

Sizing

Answer 9

You could see the response in Fiddler: http://www.fiddler2.com/fiddler2/

That's nice tool for such things!

Vizcacha

I know about Fiddler, but it seems overkill for something this simple. – Santalaceous