119 lines
2.2 KiB
Markdown
119 lines
2.2 KiB
Markdown
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---
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title: JSON Syntax
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---
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## JSON Syntax
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The JSON syntax is a subset of the JavaScript syntax.
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### JSON Syntax Rules
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- JSON Object is an unordered set of name/value pairs.
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- Object names are followed by a colon (:).
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- Curly braces {} are used to hold objects. Object begins with { (left curly brace) and ends with } (right curly brace).
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- JSON Object data is represented as a collection of name/value pair.
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- Each name/value pairs are separated by comma (,)
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- Square braces [] are used to hold Arrays.
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### JSON Data - A Name and a Value
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JSON data is written as name/value pairs.
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A name/value pair consists of a field name (in double quotes), followed by a colon, followed by a value:
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```
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"handle":"moghya"
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```
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- JSON names require double quotes.
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### JSON - Evaluates to JavaScript Objects
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The JSON format is almost identical to JavaScript objects.
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In JSON, keys must be strings, written with double quotes:
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- JSON
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```
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"handle":"moghya"
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```
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- JavaScript
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```
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handle:"moghya"
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```
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### JSON Values
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In JSON, values must be one of the following data types:
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- a string
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- a number
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- an object (JSON object)
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- an array
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- a boolean
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- null
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In JavaScript values can be all of the above, plus any other valid JavaScript expression, including:
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- a function
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- a date
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- undefined
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### JSON Uses JavaScript Syntax
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Because JSON syntax is derived from JavaScript object notation, very little extra software is needed to work with JSON within JavaScript.
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With JavaScript you can create an object and assign data to it, like this:
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```
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var person = {
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"name":"Shubham",
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"age":21,
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"handle":"moghya",
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"website":"http://moghya.me/"
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};
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```
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You can access a JavaScript object like this:
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```
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//returns moghya
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person.handle;
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```
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It can also be accessed like this:
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```
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//returns http://moghya.me/
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person["website"];
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```
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### Arrays in JSON
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```
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var team = {
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"name":"novatoscript",
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"members" :
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[
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{
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"name":"Shubham Sawant",
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"age":21,
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"handle":"moghya",
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"website":"http://moghya.me",
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},
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{
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"name":"Saurabh Banore",
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"age":21,
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"handle":"banoresaurabh",
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"website":"http://banoresaurabh.me/",
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}
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]
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}
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```
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### Example
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A very large example of JSON is [here!](http://moghya.me/js/profile.json).
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