MVC 4 question about JSON and XML output by Web APIs

Contents

 

Today, when I was playing a web API problem, I found that the output JSON was changed to XML.

 

The problem is as follows:

When IE is used, JSON is returned.

We can see that

The first time is XML, and the second time is JSON.

Later I found the rule:

The browser requests are different.

IE is JSON

Firefox is XML

 

Then, test it in fiddle.

 

 

The result is as follows:

If accept: Application/XML is added, XML format data is returned.

If you do not add or change it to accept: Application/JSON, JSON data is returned.

 

CodeRoughly as follows:

 

 
Public ClassImagewordapicontroller: apicontroller
 

 
{
 

 
PublicMiniwordimagesjson getimages (StringID)
 

 
{
 

 
..................
 

 
ReturnNewMiniwordimagesjson {id = 1 };
 

 
}
 

 
}
 

 

Later read http://stackoverflow.com/questions/9847564/how-do-i-get-mvc-4-webapi-to-return-json-instead-of-xml-using-chrome

Don't understand.

Solution

In fact, you can do this:

1. In the configuration file

 

Globalconfiguration. configuration. formatters. jsonformatter. mediatypemappings. Add (NewQuerystringmapping ("JSON","True","Application/JSON"));
 

 

 

Http://111.com/a/1? JSON = true

Http://111.com/a/1? Xml = true

 

To limit the returned status.

2. During the request

Add accept: Application/XML to request the return status. Figure above

Add content

If you force the output of JSON directly on the server side, you can do this directly.

 
Globalconfiguration. configuration. formatters. Clear (); globalconfiguration. configuration. formatters. Add (NewJsonmediatypeformatter ());
 

Clear the file before adding jsonmediatype

Although this scheme is cleared, adding it will cause some resource waste.

It is better to control at the source, always return the jsonmedia type

Public ClassJsoncontentnegotiator: icontentnegotiator {PublicContentnegotiationresult negotiate (type, httprequestmessage request, ienumerable> mediatypeformatter <Formatters ){VaRResult =NewContentnegotiationresult (NewJsonmediatypeformatter (),NewMediatypeheadervalue ("Application/JSON"));ReturnResult ;}}
 

Then register

Config. Services. Replace (Typeof(Icontentnegotiator ),NewJsoncontentnegotiator ());
 

 

 

 

References:

Http://stackoverflow.com/questions/12629144/how-to-force-asp-net-web-api-to-always-return-json/12629311#12629311