Beginner PHP Tutorial - 200 - Final PHP Video!!! Video Lecture | PHP for Absolute Beginners: From Novice to PHP Master - Web Development

so let's just run through this to make
sure you understand we've got a public
function constructs we've got a
constructor here which is reading in
some arguments from when we initiate our
class then what we're doing is we're
checking to see if this Connect function
returns a true value and we haven't done
anything with the connect method sorry
yet but when we do if it returns a false
value we're going to say connection
failed otherwise if it returns a a true
value we're going to say connected to DB
host so what we could say is again we
could say if this connect DB host DB
username DB password so if this equals
true basically because we don't have
this exclamation mark here as our not
saying is it not true so let's just test
this out let's return true automatically
in this connect function so when we cool
the connect function or the connect
method here and here we're automatically
returning true so therefore we're going
to say connected to and it's going to
successfully work so at the moment if we
refresh our page you'll see that there's
nothing on there because we need to
create a new instance of this connect
this database Connect class so
connection equals database connect and
remember we need to supply it with three
arguments which is the host
the username and the password so this
actually at the moment isn't using the
MySQL connect function to see if it's
worked on our we're just supplying
through three arguments and then we
automatically going to return connected
to local host because we're
automatically returning true on this
connect method so let's refresh you can
see oh no database connect oh sorry okay
so I've put connection equals database
connect we need connection equals new
database Connect because now what PHP
thinks I'm doing here is it thinks I'm
calling a function when in fact is not a
function it's a class or an object so
let's refresh connected to localhost
okay that's fine
we presume that would happen because
we've automatically returned true here
now let's try to automatically return
false to see what happens and you can
see that it says connection failed so we
know that everything is working up until
now now all we need to do is inside our
public function connect we need to let's
just get rid of that inside our method
connect I mean we need to do a MySQL
connect
and we need to check if this has
connected and then we can return a
specific value so we just say if MySQL
Connect will put not in there so if the
connection is false or if it hasn't
worked and we're supplying remember
database host from the arguments up here
database username again from the
argument here and then also DB password
so if that hasn't worked bear in mind we
already we automatically connect to our
database because we supply this command
but this if statement is checking if
it's not connected properly then we
return false so hopefully now you can
see it start coming together else
returned true okay so what we're doing
now is we're connecting to our database
if it hasn't worked we're returning
folks back to this construct here where
we've made our check and otherwise we're
returning true back to not the construct
but the check in here where we're using
this connect
so now let's double check that and let's
refresh our page to see if we don't have
any errors okay everything looks okay
let's create a new instance of our
connect and this will either work or not
so we can say connect equals database
connect and then we can put our
arguments in here now just before that
in this construct just above the if I'm
going to say echo attempting connection
okay so I'm writing attempting
connection and then what will either get
is connection failed or connected to our
server so a database connect we need to
specify the host which is for me
localhost the username which is root for
me and I don't have a password set but
let's just let's just get rid of that
for now and refresh and see what happens
again I've done the same thing and I
haven't used my new keyword in there
let's refresh and you can see we've got
a tempting connection and then
connection failed so now let's try with
the correct credentials I'll type my
username in there so this will
successfully connect to my database so
let's check if it works okay and it says
connected to localhost so with what
we've learnt already and with using this
constructor here we've automatically
taken in some arguments from when we
create a new instance of our class we've
read these in and we've used a function
called connect which has allowed us to
connect to our database now why is this
useful why might this be useful in a
real life situation because it's just
simply an easier and tidier way to
connect to your database and return
errors you can see that here we've got a
really neat way to show that we've
connected to our database we don't
always need to tell our users that we've
connected to our database but let's say
for debugging purposes you wrote all
your code like this you're going to have
detailed error information sent straight
back to you without just using a
procedural code where you will maybe say
or die kill the page here we get
specific information and all we need to
do is say connection equals new database
connect and we're basically done