Any another code without using this give same output


#1


var james = {
    job: "programmer",
    married: false,
    sayJob: function() {
        // complete this method
        console.log( "Hi, I work as a "+this.job)
    }
};

// james' first job
james.sayJob();


// change james' job to "super programmer" here

james.job="super programmer";
// james' second job
james.sayJob();


#2

pleas any one tell me detaliled knowledge about this..why 'this' is important in javascript


#3

@sahil1758

- - - B a s i c s - - -

Each Object has one or more properties.
Each property consists of a property-key and it's associated value.

 var object1 = {
              name: "First"
              }

So object1 has 1 property with
a type property-key name
and it's associated value "FIRST" (which in this case is a "string-value")
OR

var myObj = {
         type: 'fancy',
         disposition: 'sunny'
        }

myObj has 2 properties seperated by a comma-,,
a property with property-key type and an associated-string-value 'fancy'
a disposition-property with property-key disposition and
..an associated-string-value 'sunny'.

= = = = = = = = = = = = = = = = = = = = = = = = = = = =

var james = {
    job: "programmer",
   married: false,
   sayJob: function() {
          // complete this method
          console.log("Hi, I work as a" + this.job);
    }
 };

Description of the james object.
The james object has 3 properties which are seperated by a comma-,

there is a job property with property-key job and it's associated string value 'programmer'
there is a married property with property-key married and it's associated boolean value false
there is a sayJob property with property-key sayJob and it's associated anonymous function VALUE
( they also would 'say', the james-object has the sayJob()-Method )

access via dot-notation

james.job ==> you will get the associated string VALUE of the job property-key, thus
you get the string VALUE 'programmer'

james.married ==> you will get the associated boolean VALUE false

james.sayJob ==> you will get the associated anonymous function VALUE
to call/execute this method you add a pair of parenthesis-( )
james.sayJob();

access via the square-bracket-notation

1 using the literal property-key

james["job"]
james["married"]
james["sayJob"]()

2 using the property-key by reference (=== via a variable )

var propertyKey1 = "job";
var propertyKey2 = "married";
var propertyKey3 = "sayJob";
james[propertyKey1] ==> you will get the associated string VALUE of the job property-key, thus
you get the string "programmer"

james[propertyKey2]
in this case you will get the boolean VALUE of the married property
being false

james[propertyKey3]();
would =display= "Hi, I work as a programmer"

+++++++ this explanation +++++++++++
I defined an extra property in the james object.
in this case a method
as there is a property-key sayJob2
with it's associated value being a function...

var james = {
    job: "programmer",
    married: false,
    sayJob: function() {
              // no PARAMETER used
              // job-Value is picked up from within this Object
              console.log("Hi, I work as a" + " " + this.job);
    },
    sayJob2: function(job) {
              // 1 PARAMETER is used as =local= VARIABLE
              // job will get the  Value as you call providing 1 ARGUMENT
              console.log("Hi, I work as a" + " " + job);
    }
 
 };

 james.sayJob();

 james.sayJob2("xx");

An object has one or more properties separated by a comma-,
A property consists of a property-key and it's associated value.
The associated value can be anything
from an Array [] , null, "string", number, true , _an Object {} or a function.

If the associated value of a property-key is a function
we are calling this property a METHOD.
(if in the course they ask you to create a method you will now know that
you have to create a function within an object using the function-name
as property-key)

Normally if you are using the this keyword in a Method,
you are referring to the property of the object of which it is part of.

So in our case:
james.sayJob();
would translate to
console.log("Hi, I work as a" + " " + "programmer");

A good article about this:
http://stackoverflow.com/questions/3127429/how-does-the-this-keyword-work
http://stackoverflow.com/questions/80084/in-javascript-why-is-the-this-operator-inconsistent
with google search
== discussions / opinions ==
javascript this explained site:stackoverflow.com

Reference::

google search
== the Book ==
javascript this site:developer.mozilla.org
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this
Have a read through
http://stackoverflow.com/questions/4354418/var-vs-this-vs-constructor-parameter-variables
and


http://stackoverflow.com/questions/3127429/how-does-the-this-keyword-work


#4

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