recently I have got a lot of requests to create a video tutorials based about
object-oriented programming so I have decided to create a three part video
series where I'm going to teach you about basics intermediate and advanced
settings based about object-oriented programming so in this first three that
I'm going to talk about the concept of object-oriented programming I will show
how to declare new class helped to create setters and getters what are the
properties and etc so let's do it
hey what's up guys Senaid here from codingpassiveincome.com the place where I help
others to become a web developer much easy and fast and then they will do it
on their own so if that is something that interests you consider subscribing
so now in order to explain the concept of object-oriented programming
let's imagine that you want to create our human population that we have on
this planet so as you can see we have over seven billion people in this world
and the problem is that if we want to do it from the coding side it will be
really challenging because we will need to create the same thing seven billion
plus times so now if we think about this and look each human we can notice some
patterns almost 99% of us have the same functionality the same visual appearance
so let's say that all of us have a head we have eyes we have nose mouth neck
arms somebody 2 legs etc we also have some here and really it's not important
so now if we think as a not only web developers but programmers in general we
will be smart if we create this as something abstract and then we just
multiply this a lot of the times but of course there are some things that are
different between each of us so some of those things are first-name lastname
maybe skin colour the hate debate etc and now with this object-oriented
programming what we are going to do we will just create something that is
almost the same for all of us and then to this class we will just give an
options to modify this class and then on that we create and new objects that are
basically everything the same with just the small difference so let's
say now if we have this class and we want to create a new person we will just
create it very simple we will just create create me new instance of this
class and we will get a new object which in our case of course is a new human ok
so this one will look like this and now all we need to do is just to apply and
call some methods which a procedural programming is function to just create
the difference between those two and now of course we will dust in a few lines of
the code create a lot of those so I know that this at the moment is very hard to
imagine but just remember that with the object-oriented programming what you are
doing we are actually creating one class that will have learning the same and
then in order to create a new object or instance of the this same class we will
just use one or two lines of the code and the calling the methods we will make
difference between each of them so as you can see now the object-oriented
programming is probably at the beginning fun and then you will find it very
frustrating and challenging and later you'll find it will be very cool so with
that being said please stay with me through all those steps and I'm sure
that one day we'll be happy that you took these steps so let me now show you
how to write the code and actually create some classes so now as I
understand the basic concept of object-oriented programming
let's create some class and set some setters and getters to this class so in
order to create some class we need to use the keyword class and after that we
need to give a name to this class so let's say it I will name it the person
and then we just need to open and close the bracket so now after this as you can
see this class doesn't have any method inside it so we can create some
and now before we even create any I want to show how to create a new object from
this class so let's say it will have a name maybe I better say Smith equal and
I will just say new person ok and now let's just try to execute this
I will hit refresh and there is nothing which means that our code is completely
defined but let's say that I'm going to create something that we are calling
construct ok and now you may ask so what is this function construct basically it
is a function that is called every time that we use the keyword new so if we do
not create one construct we won't call any but basically by default it will be
cold if it exists okay so let's try to do this and I will say echo new object
has been great okay and now let's try to refresh and now as you can see inside
our construct class we have got a response ok as you can see I didn't call
any method but just by using the word new this has been cold so let's say that
we will have one variable here so I will maybe say name and by default I will
just say that the name will be used ok and now inside this construct we can
pass some name so let's say name ok and in order for me to change this name
I will need to use the word this which means that we are referencing to the
current object and then I will say name = new name ok and now by default I
can say that this is an empty so I will say here F name is not empty we will
change the name of this person and then let's say I will create a new function
that we usually call getters sows a public function get name ok and I will
just say echo your name is and then he I will does say again this name ok and now
when I create a new person I will say he Senaid->getName okay so let's try to
refresh and now it says your name is user and the reason for that is because
of the construction we didn't specify any name so if I wanted to say Sanae I
was specified here and now if I refresh you can see that I will get your name is
Senaid and now as you can see at the moment we do not have any option to
change this name instead of at the time of the construction of the class so it
will be great to have a function that we call a setter which means that you are
able to change something inside this class souse a public function set name
and then I will specify name and say this->name = name okay so now
if we try to use it this way I will hit refresh and since your name
is user okay and here I will say Senaid set name so I will see Senaid so maybe
it will be better if instead of Senaid we use person okay so the name will be
Senaid and then again I want to say get name okay so let's see what we will have
refresh so as you can see it says your name is user and again it says your name
is Sydney which means that by doing this we'll have called the setters with the
name set name and then we have updated this variable okay so now if anytime you
want to get or to just change something you will always have to create setters
and getters now you may ask what if I try to do this so let's say I will touch
the like this and I will say echo person what do you think it will happen now if
i refresh now it says that object of class person could not be converted to
string which means that we are not able to just say echo person but we can do
something like this create a new function to strain which means that now
we are able to call it and to create some string so I can
say that we will return your name is by this okay and now if we refresh you can
see now that it is working but since we have he also get name and basically this
is the same we can change this to the return and here we will does say this
get name okay so what we are doing here basically from the method to string we
are calling the method get name and then this get name will return this message
so let's try refresh and it is the same result and of course if we want to
specify some name we can do it and this will be changed so as you can see now
this is where the real user is we can have different functions and each of
these function will do something really awesome at the moment it's really not
doing anything special but the understanding of those basics is
extremely important so let's now try to improve it even more so let's say that
this get name which by default not by default but this is the best practice is
that when you have the name of the function it should return only that so
if we say here get name then this function should return only the name and
not like we had in the previous example other characters so here now let's say
that we want to also set create a setter and getter for the last name
maybe I'll just duplicate this and I will just say said last name so say he
was named okay and now the same he'll get last name
okay and at the top i will also define variable last name and for the last name
by default it will be empty and now on the construct i will set that we are
also able to provide first and last name okay i will duplicate this
my name okay so now when we create some person we are able to specify the first
name and also the last name and also we have setters and getters for this person
and as you can see now the function to string by default is returning only the
get name so maybe we should improve itself declare a new function and say
identify and then I will say return my name is and then I want to say this name
and this last name we could also here called methods for this but there isn't
any reason for that and then here in the third string I will just say this
identify okay of course we can add some other functions and properties like age
skin color etc but for now let's use it just this way okay and now as you can
see here we have person John and then let's specify some last name let's say B
okay that's person number one okay and then we also want to have person number
two so I will say person and this one will not have any name or last name I
want to set for that person using methods so I'll say person to say
name and I will say his name and then for the person - I've also said last
name I'll say as signals okay so those are just two persons and now let's try
to identify each of these persons I'll say echo person one so let's see what
the result will be so I will fresh and as you can say see it says my name is B
so let's see why is that
Sunday the program is here we made small mistake okay let's try again so for the
first person says my name is don't be okay and now let's say they'll just make
one new light and say echo person to identify so as you can see now I'm
directly calling the method identified instead of doing it this way so let's
try and as you can see now it says my name is Tom B and for this one it says
mine is Bessie note so let's see what is the problem with that okay here should
change this okay and let's try again okay and now as you can see we have
created a functionality where we are able to create two different persons and
now for each person we are able to manipulate in our case the name and last
name and we are able to get those informations on two different ways and
now as you can see this code is completely the same for both persons so
now in order to make our code a lot more readable you just can cut this I will
create a new file so let's say we will name it person dot class.PHP okay
and of course you can specify this dot class it's not a must but it's just a
good practice so that we know that this file contains some class okay and now we
will just include it here so I will say include person dot class.PHP and now
if we refresh the result will be the same
and now our code is really readable we don't have a lot of the functions and we
didn't write all of this code two times we made it only the ones so maybe at the
moment you are not able to see the real use it and how much powerful
object-oriented approach is so for that reason in the next two videos I'm going
to talk about intermediate and advanced it object-oriented programming so guys I
hope that you like this video if you do please like it and share with your friends
and also if you have any questions please ask in the comments below
take care
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