var site="qj"

let edu={
    site:"hdr",
    show:function(){
        console.log(this.site);
        function render(){
            let site="11";
            console.log(this.site);
        }
        render()
    }
}
console.log(edu.show());

其中

function render(){
            let site="11";
            console.log(this.site);
        }
 

是普通函式，this的指向是window。

let Lesson={
    site:"houdunren",
    lists:["js","css","mysql"],
    show:function(){
        //方式1，傳給self，然後傳到函式中
        const self=this;
        return this.lists.map(function(value){
            return `${self.site}-${value}`;
        })

    }
}
console.table(Lesson.show());

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