| 123456789101112131415161718192021222324252627282930313233343536373839404142434445 |
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- </head>
- <body>
- <!--
- 1、instanceof是如何判断的？
- *表达式：A instanceof B
- *如果B函数的显式原型对象在A对象的原型链上，返回true，否则返回false
- 2、Function是通过new自己产生的实例
- -->
- <script>
- /*
- 案例1
- */
- function Foo() { }
- var f1 = new Foo()
- console.log(f1 instanceof Foo) //true
- console.log(f1 instanceof Object) //true
- /*
- 案例2
- */
- console.log(Object instanceof Function) //true
- console.log(Object instanceof Object) //true
- console.log(Function instanceof Function) //true
- console.log(Function instanceof Object) //true
- function Foo() { }
- console.log(Object instanceof Foo) //false
- </script>
- </body>
- </html>
|
