What is JSON?

• JSON stands for JavaScript Object Notation. It's a lightweight data format used to store and exchange information between systems, especially in web applications.

• Think of JSON as a way to write and organize data in a clear, structured format.

Why JSON?

1. Human-readable: Easy to understand and write.
2. Language-independent: Used in many programming languages (not just JavaScript).
3. Popular in APIs: Data sent between a server and a client (e.g., a website and a database) is often in JSON format.

What Does JSON Look Like?

{
  "name": "Alice",
  "age": 25,
  "isStudent": false,
  "skills": ["JavaScript", "Python", "HTML"],
  "address": {
    "street": "123 Main St",
    "city": "Wonderland"
  }
}

How to Read This JSON Example?

1. Curly Braces {}: Represent an object or a collection of data.
2. Key-Value Pairs: Each piece of data has a "key" (name of the data) and a "value" (the actual data). "name": "Alice": Key is name, and the value is "Alice".
3. Data Types in JSON: Strings: Text enclosed in double quotes ("Alice"). Numbers: 25, 3.14. Booleans: true, false. Arrays: Lists of values (["JavaScript", "Python", "HTML"]). Objects: Nested data, like the "address" part.

JSON in Action

Imagine a website showing user profiles. The server sends user data to the browser in JSON format:

{
  "users": [
    {
      "id": 1,
      "name": "John",
      "email": "john@example.com"
    },
    {
      "id": 2,
      "name": "Jane",
      "email": "jane@example.com"
    }
  ]
}

Why Use JSON Instead of Something Else?

1. Simple Structure: Easy for humans to write and for machines to parse.
2. Compact: Takes up less space compared to other formats like XML.
3. Integration with JavaScript: JSON works seamlessly with JavaScript.

How to Work with JSON in Code?

Example in JavaScript:

// JSON data as a string
const jsonData = '{"name": "Alice", "age": 25}';

// Parse JSON into an object
const user = JSON.parse(jsonData);

console.log(user.name); // Output: Alice

// Convert object to JSON
const newJson = JSON.stringify(user);
console.log(newJson); // Output: {"name":"Alice","age":25}

Example: PHP Array to JSON:

<?php
$data = [
    "name" => "Alice",
    "age" => 25,
    "isStudent" => false,
    "skills" => ["PHP", "JavaScript", "HTML"],
    "address" => [
        "street" => "123 Main St",
        "city" => "Wonderland"
    ]
];

// Convert PHP array to JSON
$jsonData = json_encode($data, JSON_PRETTY_PRINT);

echo $jsonData;
?>

Example: JSON to PHP Object:

<?php
$jsonData = '{
    "name": "Alice",
    "age": 25,
    "isStudent": false,
    "skills": ["PHP", "JavaScript", "HTML"],
    "address": {
        "street": "123 Main St",
        "city": "Wonderland"
    }
}';

// Convert JSON to PHP object
$phpObject = json_decode($jsonData);

echo $phpObject->name; // Output: Alice
echo $phpObject->address->city; // Output: Wonderland
?>

Example: JSON to PHP Array:

<?php
// Decode JSON to PHP array
$phpArray = json_decode($jsonData, true);

echo $phpArray['name']; // Output: Alice
echo $phpArray['address']['city']; // Output: Wonderland
?>

Play Round Api for Understanding Json

DummyAis

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