How to convert json into array in php

In programming, converting between different data formats is a very common operation. Among them, converting data in JSON (JavaScript Object Notation) format into arrays is a common requirement. For example, in PHP, JSON format data needs to be converted into arrays for processing. This article will introduce how to convert JSON format data into an array through PHP.

1. What is JSON format

JSON is the abbreviation of JavaScript Object Notation and is a lightweight data exchange format. It represents data in the form of key-value pairs, including objects and arrays, and is easy to read, parse, and generate and parse. It is widely used in both front-end and back-end and can be used in many aspects such as data transmission, storage and display.

2. Conventional form of JSON format

The following is an example of conventional JSON format (the following code comes from Alibaba Cloud API Gateway):

{
    "RequestId": "C28F393F-2F69-483F-87B6-C08B9151C693",
    "Code": "Success",
    "Message": "成功",
    "Datas": [
        {
            "Name": "Jack",
            "Age": 28,
            "Address": {
                "Province": "Guangdong",
                "City": "Shenzhen",
                "Street": "Nanshan District"
            }
        },
        {
            "Name": "Lucy",
            "Age": 25,
            "Address": {
                "Province": "Hubei",
                "City": "Wuhan",
                "Street": "Hongshan District"
            }
        }
    ]
}

In the above example , the first line specifies the request ID, and the next three lines are the return status code, message and data content. The data content includes an array, which contains two objects, each object has 3 attributes (name, age and address, and the address contains 3 attributes: province, city and street). In actual applications, JSON format data may have more attributes and more complex structures, but the above form is a typical example.

3. How to convert data in JSON format into an array

In PHP, you can convert data in JSON format into an array through the built-in function json_decode(). The specific function definition is as follows:

mixed json_decode ( string $json [, bool $assoc = FALSE [, int $depth = 512 [, int $options = 0 ]]] )

Among them, $json is the JSON format string to be decoded; $assoc identifies whether to return an associative array instead of an object; $depth represents the maximum recursion depth; $options represents when decoding Some special options (such as allowing "/" escaping when decoding, etc.). The following is a simple example:

<?php
  $json = &#39;{"name":"Jack","age":25,"address":{"province":"Guangdong","city":"Shenzhen","street":"Nanshan District"}}&#39;;
  $array = json_decode($json, true);
  print_r($array);
?>

Running the above code will output the following results:

Array
(
    [name] => Jack
    [age] => 25
    [address] => Array
        (
            [province] => Guangdong
            [city] => Shenzhen
            [street] => Nanshan District
        )

)

In the above example, a JSON format string is first defined. Then use the json_decode() function to decode the string into an array and assign the result to the $array variable. Finally, use the print_r() function to output the contents of $array. You can see that the output result is a nested associative array, including name, age, address, etc.

It should be noted that the result returned by the json_decode() function depends on the value of the second parameter $assoc. When $assoc is false, the function returns the decoded JSON data as an object (stdClass); when $assoc is true, the function returns the decoded JSON data as an associative array.

4. Summary

Converting JSON format data into an array is a very common operation, which can be achieved in PHP using the built-in function json_decode(). When using this function, you need to pay attention to the value of the second parameter $assoc to determine whether the result returned after decoding is an object or an array. At the same time, it is also necessary to note that data in JSON format may be complex, and you need to read the document carefully to understand the attributes and its structure. Through the introduction of this article, I believe you have already understood how to convert JSON format data into an array in PHP.

The above is the detailed content of How to convert json into array in php. For more information, please follow other related articles on the PHP Chinese website!