Beginner PHP Tutorial - 46 - String Functions: String Length Video Lecture | PHP for Absolute Beginners: From Novice to PHP Master - Web Development

hi this is Alex from PHP academy' org
and in this tutorial for the new Boston
I'm going to be talking about string
length and why it's useful and how we
can do now as you know we can create a
variable with a string type which will
automatically be created with us so
let's do that now I'm going to create
string and then I'm going to call this
and/or set this to the value of Alex so
we've got four characters in here now
what we might want to do is we might
want to find out how many character is
character characters sorry are in this
string so we can go ahead and we come up
and create a new variable and I'm going
to call this string length and that is
going to be equal to we need to call a
function now to be able to grab the
length of string so I'm going to say STR
Len so short for string length and then
inside here we're going to take one
parameter or one argument and this is
going to be the variable of the string
that we want to count so we want to
count the specific amount of characters
inside a string here so I could in fact
just to splice apply this with an amount
of characters so I could say how many
characters does this have okay so now
what we can do is down here we can echo
out string underscore length now let's
just preview that in our browser and see
what happens
so you can see we've been returned with
the result 35 now that in fact means
that there are 35 characters in this
string obviously not including the the
single quotation marks on the outside so
let's just test this out something we
can monitor let's just type the
character a now let's come and refresh
and you can see that says one so let's
look at how we can probably like
calculate a predefined string so what
I'm going to do is I'm just going to pop
the variable name in there and that will
transfer this data here into here so now
we should have the result for
okay so we've determined how to count a
string length and then how to output the
string length but why would we want to
do this now there are a few different
reasons why we reduce this STR Len
function now the first main reason would
be obviously to count the amount of
characters but we might want to loop
through using loops in PHP loop through
each character and the way we do this is
we either use I mean I would personally
as a for loop or you could use a while
loop a do while loop or a for loop so
let's say we were using a for loop to
loop through now maybe maybe I won't
show you the example in this case
because you may not have looked to for
loops yeah however to loop through a
certain amount of characters we need to
first loop through the first character
then the second character then the third
character and then the last character
now how will we know when to end this
loop how would we know when we reach the
end of a certain amount of characters
well the answer is absolutely simple we
would start at one and we would end at
the string length because in actual fact
that if we were looping with loop once
twice three times and four times and
would end to loop through each character
of this now let me just actually start
up an example because this is going to
allow you to see it see a lot better so
I'm going to say four and I'm going to
create a variable with the value one so
if you haven't looked at for loops yet
go and have a look at that and you'll
understand what's going on here so for x
equals one we're going to say while X is
smaller than or equal to something now
something here is going to be the length
of the string and after this we need to
say X plus plus we're incrementing each
time so the string length here needs to
be determined so now what we can just do
is put string lengths straight into
there now what happens when we echo our
X let's just keep an eye on what happens
we can append a break to this as well so
let's go and refresh
you can see that we've got one two three
four and four that's because we're
already occurring that out there so we
can get rid of that
okay so we're occurring one two three
and four so you can see that already
we're counting through and we're only
looping our four times because we've
determined that the string length is
there so this example might not
particularly make sense to you now but
later on when you need to loop through a
string or well yeah a string if you want
to loop through a string you'll find
this useful because you can determine a
string length and then set a boundary
for how many times you want to loop
specifically