Arguments : An array-like object which accessible inside functions that contains the value of the arguments passed to that function
Function : A sort of object, and object has property. If property has function, we can call this property as method.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<script>
function sum(){ //function sum, () is parameter
//if there is no parameter(), or it is different from the number of parameters, it can be
var i, _sum=0;
for(i=0; i<arguments.length;i++){
document.write(i+arguments[i]+'<br />');
_sum+=arguments[i];
}
return _sum;
}
document.write(sum(1,2,3,4)); //arguments 1,2,3,4
//it is okay if there is different number between parameter and arguments
function one(arg1){
console.log(
'one.length', one.length, //one is funtion, how many function of this name? 1
'arguments', arguments.length //how many arguments it have? 2
);
}
one('val1','val2');
function func(){ //func is a function, it is an object therefore it can have method which is built-in methods(native code) by default Javascript provides
}
o1={val1:1, val2:2, val3:3}
o2={v1:10, v2:20, v3:30, v4:40}
function sum(){
var _sum=0;
for(name in this){//this means var this=o1;
_sum+=this[name];
}
return _sum;
}
alert(sum.apply(o1))//the moment this is executed, sum method executing of object o1
alert(sum.apply(o2))
</script>
</body>
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