format JSON – JSON is a format used for data exchange and is the acronym for JavaScript Object Notation.
It is based on the JavaScript language and is used a lot for asynchronous programming, therefore with ajax, as we will see in the next lessons.
JSON is a text format, so it is a string. It allows you to aggregate data and follows the syntax of JavaScript objects.
But it can be used independently of JavaScript, in fact many programming languages ​​use it and therefore also allow you to do the parse.
A JSON object is created using a pair of curly brackets that are used to contain the whole object. Then, inside these brackets, the various properties are inserted indicating key-value pairs and making sure to use double quotes for both the key and the value. Each property of the object is separated by a comma.
format JSON – example
Let’s take some examples of JSON objects.
This is an example of JSON format:
{
"type":"Fiat",
"model":"500",
"color":"white",
"powerSupply":"gas",
"year":"2010"
}
The json data is described as key-value pairs, in this example we have an auto object with some property, as for example: tyoe, model, color, ecc.
The JSON object can be even more complex, as for example this API:
format JSON e JavaScript
A JavaScript object is very similar to a JSON.
Let’s take an example of using JSON with JavaScript. So let’s take our usual auto object and write it as a JSON object, remembering that it’s a string.
Since it is a string we can use the simple superscript or the double superscript, without going to a new line. Or you can use the backtick (`) that is the back-to-back apex. To obtain the back-to-back apex, just hold down the ALT key and at the same time the numbers 0096 on the numeric keypad.
So let’s see a JSON object written using backticks:
var car = `{
"type":"Fiat",
"model":"500",
"color":"white",
"powerSupply":"gas",
"year":"2010"
}`;
and without:
var car = '{
"type":"Fiat",
"model":"500",
"color":"bianco",
"powerSupply":"gas",
"year":"2010"
}';
Or alternatively, you can join the strings with the + operator, as shown in the example below:
var car = '{'
+ '"type":"Fiat",'
+ '"model":"500",'
+ '"color":"white",'
+ '"powerSupply":"gas",'
+ '"year":"2010"'+
'}';
If we try to do the console.log we will notice that what we have written is not an object but a string.
console.log(car);
In the next lesson we will see how to parse the following code in order to convert it into a JavaScript object.
For more information on the format JSON, you can consult the reference site: http://json.org/example.html.