WEBVTT

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Combining data in a string
is called concatenation.

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We perform concatenation in the last video

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by adding one string variable
to another string value.

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By using double quotes,
we included the first variable

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into the string being assigned
to the second variable.

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PHP also provides two string operators for
concatenation.

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The dot and the dot equals.

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Let's take a look at how to use these
operators for more concatenation options.

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The first string operator for
concatenation is a single dot, or period.

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The dot allows us to add as many strings
together as we want in one statement.

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For example, let me duplicate this line,
then I can show you how to do

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this same thing using single quotes, but
still show the value of the variable.

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We end this string here and
concatenate with a single dot,

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concatenate again, and
start our final string.

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Our string works, and
our variable value is displayed.

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But our escape sequences
aren't working properly.

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We can remove the escape character
from before the double quotes, and

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then we can concatenate this escape
sequence, the /n, to the end.

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Now when we run our script,
just like we want.

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Remember, PHP doesn't care
about extra white spaces.

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So as long as you haven't finished
your statement with a semicolon,

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you can split this line
up however you want.

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Be aware that if you add a line
break within the quotes,

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that line break will be displayed.

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This could be a good or bad thing,
depending on the desired results.

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Early on I said, with great power
comes great responsibility.

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So just because you can concatenate
your string over multiple lines

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doesn't mean that you should,
splitting up a statement

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into multiple lines can make
it extremely hard to follow.

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If you are going to split the line, try
to make it as easy to read as possible.

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Indent the next lines and start each
line with a concatenation character.

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Notice that extra space
right before Hello Alena?

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That's because our string is split between
two lines, and it's within single quotes.

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So it's trying to display the characters
exactly as they're shown.

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I could end my string here, and
then start my string again down here.

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Now we have a single line.

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Now this is easier to read, but

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it's probably not the best choice if
you're going to use multiple lines.

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You're probably better off using
the second operator, the dot equals.

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This concatenation assignment
operator appends or

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adds the argument on the right side
to the variable on the left side.

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This can make multiple lines
easier to read because

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each line is a complete statement.

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You finish each line with a semicolon, and

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then you add to the variable, string one,

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dot equals, Hello, end with a semicolon,

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and again, string one,

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dot equals name, end with a semicolon.

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String one, dot equals,

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end with a semicolon, and our last line.

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Now let's run this script again.

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Same thing.

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This is the same as saying
string one equals string

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one concatenated to this next string,

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because it appends or adds the new
value to the end of the string.

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If I wanted to add a string to
the beginning instead of the end,

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I could do just like this line,
but instead,

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I add to the beginning,
I am, in the concatenation.

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Now let's run this script.

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I am learning to display
Hello Alena to the screen.

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Besides making multiple
lines easier to read,

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making each line a separate statement
will allow you to add other

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code between the lines,
such as adding a comment.

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Prepend to a string.

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To summarize concatenation, if you want
to add a single variable to a string,

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you can include that variable within
your double quoted assignment.

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If you are concatenating a single line,

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you would use a single
dot between each string.

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If you are concatenating multiple lines,

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you should use the dot
equals assignment operator.