If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail:. Code for reading and generating JSON exists in many programming languages. You can receive pure text from a server and use it as a JavaScript object.
You can send a JavaScript object to a server in pure text format. You can work with data as JavaScript objects, with no complicated parsing and translations. Report Error. The ease of retrieving data will vary based on the site providing the data, but a simple example might look like this:.
This example would request the latest feed items in JSON format and output them to the browser. The request we need to send asks for the latest photos from the user in question, along with flags asking for a JSON-formatted response. The request we need to send will look like this:. Our function will be called loadFlickr. Each photo entry is stored in an array called items , which we access in our AJAX call using feed. This can be accessed within our loop using feed. To load my Flickr stream, we would need to call our function as follows:.
Look at the source code on the demo to see how it was done. Have you used JSON before? The JSON format is often used for serializing and transmitting structured data over a network connection. It is used primarily to transmit data between a server and web application, serving as an alternative to XML.
It is a much-more compact way of transmitting sets of data across network connections as compared to XML. You can accomplish the same effect with JSON and its mark-up is almost exclusively dedicated to the data itself and not the underlying structure. I like JSON mainly because it's so terse. For web content that can be gzipped, this isn't necessarily a big deal hence why x html is so popular.
But there are occasions where this can be beneficial. For example, for one project I was transmitting information that needed to be serialized and transmitted via XMPP. Since most servers will limit the amount of data you can transmit in a single message, I found it helpful to use JSON over the obvious alternative, XML.
As an added bonus, if you're familiar with Python or Javascript, you already pretty much know JSON and can interpret it without much training at all. Sometimes technicality is given where none is required, and while many of the top voted answers are accurately technical and specific, I personally don't think they are any more easy to understand, or succinct, as what can be found on Wikipedia, or in official documentation.
The way I like to think of JSON is exactly what it is - a language within a world of different languages. Using a real world example, let's pretend we have three people. One person speaks Igbo as their native tongue.
The second person would like to interact with the first person, however, the first person speaks Yoruba as their first language.
Thankfully, the third person in our example grew up speaking English, but also happens to speak both Igbo and Yoruba as second languages, and so can act as an intermediary between the first two individuals. In the programming world, the first "person" is Python, the second "person" is Ruby, and the third "person" is JSON, who just so happens to be able to "translate" Ruby into Python and vice versa! Now obviously this analogy isn't a perfect one, but, as someone who is bilingual, I believe it's an easy way to look at how JSON interacts with other programming languages.
We have to do a project on college and we faced a very big problem, it is called Same Origin Policy. Amog other things, it makes that your XMLHttpRequest method from Javascript can't make requests to domains other than the domain that your site is on. For example you can't make request to www. That is one problem where you could use JSON perhaps. The important thing we have to remember is that, if we have to build the "Employee" class or modal with elements without JSON method we have to parse everything when creating class.
But with JSON we can define the objects inline only when a new object for the class is defined. It's very simple. Think of it as an alternative to using XML for transferring data between software components. For example, I recently wrote a bunch of web services that returned JSON, and some Javascript developers then wrote code which called the services and consumed the information returned in that format. Its in key value pair as the JavaScript is. Nowadays many of the social media sites are using this.
Although I don't see this as robust as XML with respect of data types. JSON is bit lacking in this. JSON can also start as an array, which uses the square bracket [ symbol to signify the start of the array.
JSON can contain object or array. JSON structures data by key-value. This will affect the way we parse JSON in the next steps. In the Java context, one reason why JSON might want to be used, is that it provides a very good alternative to Java's Serialization framework, which has been shown historically to be subject to some fairly serious vulnerabilities. Java's Serialization was initially meant to translate data structures into a format that could be easily transmitted or stored.
JSON meets this requirement, without the serious exploits referred to above. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. What is JSON and what is it used for? Ask Question. Asked 12 years, 11 months ago. Active 4 months ago. Viewed k times. Improve this question. TylerH
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