JavaScript json to entity

In recent years, front-end development using JavaScript to operate JSON has become an inevitable part of development work. Because JSON is concise and easy to understand, it is becoming more and more common to pass data between clients and servers. But when processing JSON data, we sometimes need to convert it into entity objects so that the data in it can be used and manipulated more conveniently. This article explains how to convert JSON to entity objects using JavaScript.

What is JSON?

JSON (JavaScript Object Notation) is an open standard format for storing and exchanging data. It is based on JavaScript syntax, uses text format to represent data, has good readability, is concise and easy to understand. The JSON format consists of key-value pairs, representing a set of JavaScript objects.

For example, the following is a simple JSON data:

{
    "name": "Tom",
    "age": 18,
    "gender": "male"
}

Among them, the attribute name is enclosed in double quotes, and the attribute value can be a string, number, Boolean value, array, object, etc. .

Two methods to convert JSON to entity

In JavaScript, there are usually two methods to convert JSON to entity objects: manual conversion method and using third-party library method.

1. Manual conversion method

The manual conversion method requires writing JavaScript code to parse JSON data and convert it into entity objects. First, we need to define an entity object, then traverse the JSON data and assign the key-value pair of each attribute to the corresponding attribute of the entity object. The following is a simple example:

// 定义实体类
function Person(name, age, gender) {
    this.name = name;
    this.age = age;
    this.gender = gender;
}

// 解析JSON数据
var jsonStr = '{"name": "Tom", "age": 18, "gender": "male"}';
var jsonObj = JSON.parse(jsonStr);
var person = new Person(jsonObj.name, jsonObj.age, jsonObj.gender);

// 使用实体对象
console.log(person.name); // Tom
console.log(person.age); // 18
console.log(person.gender); // male

Although the manual conversion method is simple and easy to learn, it requires a lot of time and energy. For situations where the JSON data structure is more complex, the manual conversion method is more complex and requires a smaller amount of code. Very big.

2. Using third-party library methods

Using third-party libraries can simplify the process of converting JSON to entities. There are currently two common JSON libraries on the market: jQuery and Lodash. The following is a sample code that uses the Lodash library to convert JSON into an entity object:

// 引入Lodash库
var _ = require('lodash');

// 定义实体类
function Person(name, age, gender) {
    this.name = name;
    this.age = age;
    this.gender = gender;
}

// 解析JSON数据
var jsonStr = '{"name": "Tom", "age": 18, "gender": "male"}';
var person = _.assign(new Person(), JSON.parse(jsonStr));

// 使用实体对象
console.log(person.name); // Tom
console.log(person.age); // 18
console.log(person.gender); // male

In the above sample code, we use the assign method of the Lodash library to assign JSON data to the entity object. Lodash's assign method can assign the properties of one or more source objects to the target object and return the target object. If the same property name exists in the source and target objects, subsequent property values ​​will overwrite the previous values.

Summary

In this article, we covered how to convert JSON to entity objects using JavaScript. Although the manual conversion method is more tedious, it can help improve your understanding of JSON and JavaScript objects. Using third-party library methods can simplify the code and achieve higher efficiency, but it requires using the corresponding library and understanding how to use it. Either way, the conversion is relatively easy once you understand the basic concepts of JSON and entity objects.

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