In JavaScript, functions can be nested.
For example:
function(){
funcrion square(x){ return x*x; }
return square(10);
}
In JavaScript, a function is bound to an object, and the function called by the object is called a method, which is easy to be confused with C#.
1. Function attributes
In the function body, you can get the number of actual parameters passed into the function through arguments.length.
function fun1 (x,y){
document.write(arguments.length()); //输出2，传入的参数是两个
}
fun1();
2. Bind the function to the object
var fun1 = function () {
alert(this.name);
}
var o = { name:"张三",fn : fun1 };
o.fn(); //输出 张三
var o = { name: "张三", fn: function () { alert(this.name) } }
o.fn(); //输出张三
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