Wie kann „diese' Referenz in setInterval/setTimeout innerhalb von Prototype-Methoden beibehalten werden?

Referencing "this" within setInterval/setTimeout in Prototype Methods

While typically, assigning an alternative "self" reference is used to refer to "this" within setInterval, this method may not be feasible for prototype methods. For instance, in the following code:

function Foo() {}
Foo.prototype = {
    bar: function () {
        this.baz();
    },
    baz: function () {
        this.draw();
        requestAnimFrame(this.baz);
    }
};

This code encounters an error because the method call to baz is taken out of context and loses its "this" reference. To resolve this issue, consider the following alternatives:

Anonymous Function Wrapper:

Wrap the method call within an anonymous function to ensure it is called immediately after accessing the baz property, preserving the correct "this" context. However, a helper variable is necessary to store the "this" reference from the outer function.

var that = this;
setInterval(function(){
    return that.baz();
}, 1000);

Fat Arrow Function Wrapper:

If arrow functions are supported, this issue can be addressed more concisely:

setInterval( () => this.baz(), 1000 );

Binding Function:

Utilize a binding function like Function.prototype.bind or its equivalent from a preferred library to preserve the "this" reference:

setInterval( this.baz.bind(this), 1000 );

Das obige ist der detaillierte Inhalt vonWie kann „diese' Referenz in setInterval/setTimeout innerhalb von Prototype-Methoden beibehalten werden?. Für weitere Informationen folgen Sie bitte anderen verwandten Artikeln auf der PHP chinesischen Website!