object_this/js_061601.html

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    <script>
        //Object this

        obj = {
            'id' : 1 ,//變數
            'name' : 'amy', //變數
            'fun1' : function(){
                //console.log('HELLO fun1 ok');
                console.log('this',this);
                console.log(this.id);
                console.log(this.name);
            },
            'sum2' :function(n1,n2){
                return n1 + n2;
            },
            'sum2': function (n1 = this.num1, n2 = this.num2) {
                return n1 + n2;
            },
            'arrowFun1': () => {    
                console.log('arrowFun1');
                console.log('arrow this',this);
            },
            
        };


        //obj['fun1'](); 不建議這樣呼叫

        //練習原本的obj
        //新增兩個變數
        //num1 , num2
        //function => sum num1+num2


        //通常會用到的都是object this
        //箭頭函式 this windows 比較少用


        //function的變數相加,讓宣告的變數呈現
        //使用return值回傳 才會知道我們存在變數的結果

        //例如:
        //let result = obj.sum2(200,200);
        //console.log(result);

        // 在obj this => obj
        //obj.fun1();
        //let mySum = obj.sum();
        //console.log(mySum);
        //let sum2 = obj.sum2(20, 30);
        //console.log(sum2);

        //let sum222 = obj.sum2();
        //console.log(sum222);


        //外部this => window
        //console.log('外部this', this);


        // 箭頭 this / arrow function
        // arrow this window
        //obj.arrowFun1();


    </script>
    

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