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Wouldn't it be nice if we could use
plain english, when writing JavaScript?

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Well thankfully we can,
with the new startsWith, endsWith and

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includes methods for a searching strings,
so first let's take a look at a couple of

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different ways we could determine if
a string started with a particular value.

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And if you're following along
you'll need to launch the latest

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workspace for this video.

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I'll open up the file starts-with.js
in the first console.log we have

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a regular expression,
testing this during to search string.

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The next console.log checks to
see if the strings zero index

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matches the string a-really.

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And finally, the third console.log
uses the ES 2015 startsWith method

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to check whether the string
begins with the string a-really.

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And if I run this file in the console,
we see that everything returns true.

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Now, it's not groundbreaking syntax but,

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compared with the regular expression and
the index of methods,

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the startsWith method makes our code
much easier to read and understand.

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Next open up the file ends-with.js.

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Not much is different here.

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The first console.log is
still a regular expression.

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Only this time we're testing that the end
of the string matches the search.

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In our index of example became a little
more complex, instead of looking for

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something at the zero index, we're now
checking the length of the string and

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subtracting the length of the test string,
so, we can find that appropriate index.

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And lastly we have the endsWith
method to check whether the string

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ends with the text hyphenated-string,
which again is much easier to read.

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Now over in the file
include.js we have something

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very similar to the previous examples.

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There's a regular expression search,
a search using indexOf,

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which expects the value
to be greater than -1.

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And then a search using the ES 2015
includes method to check whether

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strToSearch includes the word
long anywhere in the string.

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Now all three of the new methods we've
looked take an optional second parameter.

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For startsWith and
includes the second parameter is

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the index from where the search should
start, and the default index is 0.

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So for example back in my startsWith.js
file if I give the startsWith method,

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a second parameter of let's say 5 and
run the file in the console.

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Notice how the third
console.log returns false,

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because strToSearch does not start with
a-really at the position we're indexing.

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Now if I change the text to lly,
save it and

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run the file again,
we see that it now return is true.

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Now the second parameter for

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endsWith is the maximum length
of the searchable string.

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So, this string here has a length of 31.

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So, if I pass a second
parameter of say 21,

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endsWith will only use the first
21 characters for the search.

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So if I run this file in the console,
the console.log returns false.

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So I'm really excited to start using
these new string search methods and

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I hope you are too.

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Stick around for the next stage,

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where we dig into what I call
the cooler parts of ES2015.