JavaScript的Function对象

1. Function对象引入

2. Function创建方法对象

Function是js的方法对象，可以用Function实例化出任何js方法对象；

chap01/demo01.jsp

<script type="text/javascript">
function say(name,age) {
    alert(name+"今年"+age+"岁了");
}
say("张三",3);
var sayFunc = new Function("name","age","alert(name+'今年'+age+'岁了')");
sayFunc("李四",4);
</script>

http://localhost:8080/HeadFirstJavaScript/chap01/demo01.jsp
张三今年3岁了
李四今年4岁了

3. Function对象属性

chap01/demo02.jsp

<script type="text/javascript">
var sayFunc=new Function("name","age","alert(name+'今年'+age+'岁了')");
alert("sayFunc方法对象的方法参数个数："+sayFunc.length);
</script>

http://localhost:8080/HeadFirstJavaScript/chap01/demo02.jsp
sayFunc方法对象的方法参数个数：2

4. Function对象方法

chap01/demo03.jsp

<script type="text/javascript">
var sayFunc=new Function("name","age","alert(name+'今年'+age+'岁了')");
alert(sayFunc.toString());
alert(sayFunc.valueOf());
</script>

http://localhost:8080/HeadFirstJavaScript/chap01/demo03.jsp
function anonymous(name,age /*’’*/{alert(name+’今年’+age+’岁’)}
function anonymous(name,age /*’’*/{alert(name+’今年’+age+’岁’)}