Beginner PHP Tutorial - 28 - switch Statement Video Lecture | PHP for Absolute Beginners: From Novice to PHP Master - Web Development

hello this is Alex from PHP academy' de
org and in this video that I've created
for the new Boston I'm going to be
talking about the PHP switch statement
now you might have already looked at if
and if-else statements and with
incorporating an else if to do multiple
checks but what if you've got a lot of
numbers or a lot of strings to check or
something you need to check in a long
list for this we use the switch it's
basically a better cleaner and faster
way of using an if else if and then else
so the syntax for this is switch in here
we need simply a variable reference
so if up here we were to create number
equals let's say 1 we need to switch
this number and now we create a block
here which is going to have a lot of
content inside of it
we're basically evaluating this number
and we don't evaluate inside here like I
couldn't say number equals 1 for example
I would evaluate inside here and we do
this with the case keyword and we use
case and then we say what we want it to
equal to so case 1 I want to maybe echo
1 let's just indent this slightly so we
can see what we're doing and then we end
it with break and we end with a
semicolon so this is the basic structure
let me just create another one so you
can get an idea of what we're doing ok
so hopefully by now you've got an idea
of the syntax this is basically how it
looks and what is this program
essentially doing now let me just
correct go down and create a case 3 and
then we can just demonstrate what this
might be useful for so let's tab over so
what we have essentially done here is
we've created a mini program to convert
this number that's entered here into
string data so instead of writing if
number equals 1 then echo 1 else if
number equals 2 echo 2 else if number
equals 3 echo 3 end it else and we can
blah blah blah and it just gets a lot
more confusing this is a really easy way
to view yep case 1 we echo 1 case 2 we
echo 2 case three we echo 3 and this is
basically what our number evaluates to
so we could in fact change this to
string data this could be text here and
exactly the same hit could correspond to
a string data here we'll look at an
example of that in just a moment
but for now my little mini program is
going to convert the numbers the
integers remember we're not using this a
string this is a number in itself we're
converting that to the corresponding
text so now what we can do is just run
the program let's press refresh and you
can see that is outputted 1 now if we
change this number up here to 2 you can
see that we're going to say case yes it
does equal to therefore echo 2 so let's
refresh that says 2 and the same with
number 3 so let's just test that
and that says three now what happens if
we change this to something like four we
don't have a case to handle this being
equal to four so what happens you
probably guess nothing happens so we
need some way of writing here what's
going to happen if there's no case to
handle the input that we've spent the
input that is coming into this switch
statement so we use the keyword default
and we use a break as well and but in
here we can echo out just pull that in a
bit echo out let's say number not found
okay
so by default let's say for example the
number is four as we have it at the
moment the default the default action
would be to echo not not found number
not found so if we refresh it says
number not found the same of is if as if
we were to come up and change this to
minus ten for example it's going to do
exactly the same thing and we maintain
echoing out this number not found thing
okay so there's a different way that we
can structure this I'm just going to
take out the default for now let's just
get rid of everything in here as well
and we're going to basically start with
this completely different concept I'm
going to say de equals and at the moment
I'm going to set this to same Monday now
inside my switch statement remember to
change this as well inside my switch
statement I basically want a little
program that's going to tell me if this
day is a weekend or if it's a weekday so
or if you know I mean if if it is a
weekend
we could say day equals Alex and that
would not be a weekend because there
isn't a weekend day called Alex so to do
this I'm basically going to say case and
remember I said we can deal with string
data as well case Saturday
and then underneath in fact that says :
not a semicolon underneath I'm going to
say case um I'm just I'm I'm not even
breaking I'm just saying case case case
someday okay
then I'm going to break and in here I'm
going to write my output so it's a
weekend now an interesting point here
you can see that this bits turn black
that's because I'm using a a single
quotation mark within single quotation
marks I'm going to use my backslash
character to escape that now this the
program is basically saying we're
setting a date at the moment it's Monday
if if this variable here remembers we're
switching it in here if this equals if
this equals Saturday or equals Sunday
echoing it's a weekend otherwise
just pull that in a bit more echo not a
weekend so let's test this program
Monday should produce us with the result
not a weekend let's refresh not a
weekend now let's change this to
Saturday we can refresh and you can see
it's a weekend so this is a really
really good way to compare multiple
things at once and then give an output
for that and then you can always use
your default if data that's being read
into this switch statement can't be
recognized as one of the cases so that's
basically a switch statements in PHP