recently, when writing React, to define a class method, I saw the following two writing methods: fun1 and fun2, both of which are not problematic to use. After reading the introduction guide of Master Ruan, I found that they are all written in fun1, so what"s the difference between the two?
class MyClass {
name = 1;
fun1() {
console.log(this.name);
}
fun2 = () => {
console.log(this.name);
}
}react document have you read it?
fun2 = () = > {
console.log(this.name);
}
this.fun2 = () => {
console.log(this.name);
}
the first way of writing is not bound to this, the second is bound to this;
if it is not converted by babel, the browser cannot use the second way to define class, and it will report an error Uncaught SyntaxError,
is the problem pointed to by this :
React component writing is mostly written using the class constructor, where the this points to the need to make sure that it is bound to the component constructed by the class class
react users say they are familiar with the second method
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