• 코드:
​x
 
1
<!DOCTYPE html>
2
<html lang="ko">
3
​
4
<head>
5
    <meta charset="UTF-8">
6
    <title>JavaScript Object Method</title>
7
</head>
8
​
9
<body>
10
​
11
    <h1>객체의 valueOf() 메소드</h1>
12
​
13
    <script>
14
        function func(n) {
15
            this.number = n;
16
        }
17
​
18
        myFunc = new func(4);
19
        document.write(myFunc + 5);     // ①
20
​
21
        func.prototype.valueOf = function() {
22
            return this.number;
23
        }
24
        document.write("<br><br>")
25
        document.write(myFunc + 5);     // ②
26
    </script>
27
28
</body>
29
​
30
</html>