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What is a JavaScript method?
9 Jul 2016 · 196 words

Javascript contains objects, which are things like a document, a window or a frame.

Objects can also be something that you define yourself. This is an object:

var cricketer = {firstName:"Ricky", lastName:"Ponting", age:41,  batAvg: 51.85};

A method is a function that is performed on an object. Methods belong to objects.

Here’s the object from earlier, this time with a method called getSummary attached:

var cricketer = {firstName:"Ricky", lastName:"Ponting", age:41, batAvg: 51.85,

getSummary: function() {
return "Name: " + this.firstName + " " + this.lastName + " Average: " + this.batAvg 
}};

Lots of things have methods attached to them. Strings have methods:

"HELLO".toLowerCase() // "hello"

Numbers have methods through the Math object. The Math object has a set of methods that can be applied to numbers.

Math.floor(40.1)  // 40

Arrays have methods too

var firstArray = ["Hello"]
var secondArray = ["my","friend"]
firstArray.concat(secondArray)  // ["Hello", "my", "friend"]

as do functions

var add = function(x){
    sum = 0
    for(var i = 0; i < arguments.length; i++){ 
        sum = sum + arguments[i]; 
        }
    return sum;
}
array = [1,2,6,1,2,6]
add.apply(null,array) //18

and so does the RegExp type

var a = /greet/
testString = "greetings"
a.test(testString) //true

Useful things, methods.


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