what is json

#What is json?

JSON (JavaScript Object Notation) is a lightweight data exchange format that is easy to read and write, as well as easy for machines to parse and generate. .

The structure of JSON is based on the following two points

1. A collection of "name/value" pairs. In different languages, it is understood as an object (object), a record (record), a structure (struct) ), dictionary, hash table, keyed list, etc.

2. An ordered list of values ​​is understood as an array in most languages

JSON usage:

JSON represents JavaScript objects in a specific string form. If you assign a string with such a form to any JavaScript variable, then the variable will become an object reference, and this object is constructed from the string. It seems a bit confusing, so we will use an example to illustrate.

Assume here that we need to create a User object with the following attributes

User ID

User Name

User Email

You You can use the following JSON form to represent the User object:

{"UserID":11, "Name":"Truly", "Email":"zhuleipro◎hotmail.com"};

Then if you assign this string to a JavaScript variable, you can directly use any property of the object.

Full code:

<script>

     var User = {&quot;UserID&quot;:11, &quot;Name&quot;:&quot;Truly&quot;, &quot;Email&quot;:&quot;zhuleipro◎hotmail.com&quot;};
     alert(User.Name);
    </script>

The above is the detailed content of what is json. For more information, please follow other related articles on the PHP Chinese website!