React super introduction

super keyword:

参考:http://www.phonegap100.com/thread-4911-1-1.html


Es6中的super可以用在类的继承中,super关键字,它指代父类的实例(即父类的this对象)。子类必须在constructor方法中调用super方法,否则新建实例时会报错。这是因为子类没有自己的this对象,而是继承父类的this对象,然后对其进行加工。如果不调用super方法,子类就得不到this对象。



class Person {
 	constructor (name) {
  		this.name = name;
	}
}

class Student extends Person {
	constructor (name, age) {
			super(); // 用在构造函数中,必须在使用this之前调用
			this.age = age;
	 }
}

Why the official Liezi written inside a super (props):

只有一个理由需要传递props作为super()的参数,那就是你需要在构造函数内使用this.props

Examples of official learning that are written in super (props), so that the written super (props) is not in question, but also recommendations on direct written.

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Origin blog.csdn.net/Amo__/article/details/101442948