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Now that you have the skills you need
to put together any type of conditional

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expression, we're ready to look at another
way to structure conditional statements.

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PHP provides another control
structure called a switch statement.

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Switch statements are similar
to a series of if statements

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that use the same expression.

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On many occasions, you may want
to compare the same variable or

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expression with many different values and

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execute a different piece of code
depending on which value it equals.

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For example you may want to
look at the day of the week and

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perform different actions based
on which day of the week it is.

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This is exactly what
the switch statement is for.

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Let's take a look at this in action.

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Let's create a new file named switch.php.

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Open and close your PHP tags and
we're ready to get started.

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We start with the keyword switch.

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Then within parentheses,
will add the variable or

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expression we're going to evaluate.

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For our example let's
use the day of the week.

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We'll use the function
date with the lowercase l.

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Then within curly braces we're
going to add our case statements.

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We use the keyword case followed by
the value we wish to compare, Monday.

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Then we add the action we want to perform.

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Echo wash on Monday and

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then finally the key word
break followed by a semicolon.

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This tells the switch statement
that we have found a match and

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we're finished evaluating.

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I'm going to use a list of chores common
to pioneer life in 19th century America.

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You can find this code
in the teacher's notes.

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The switch statement also
allows us to add default

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in case none of the other
statements evaluate to true.

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We add default colon and then our action.

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I do not know what day it is and a break.

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Now we can run the script.

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PHP space switch.php.

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We see mend on Wednesday
because today is Wednesday.

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Let's move this date to
a variable name today.

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Now we can do some tests.

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First let's set today equal to
something that's not a day of the week.

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Now let's run our script.

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We see a default response.

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If we change today to Friday,
We now see clean on Friday.

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We can also combine value expressions
by leaving off the break.

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After a case is found, it continues to
process statements until a break is found.

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If we want to have a single message for

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the weekend, we can remove everything
between Saturday and Sunday.

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Now, when I set today equal to Saturday,
We see rest on the weekend.

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I can also add an additional
statement to Saturday.

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Echo Saturday is the weekend.

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And now when I run our script,
I see both statements.

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Saturday is the weekend
rest on the weekend.

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But if I change to Sunday,
I see only the message for the weekend.

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The switch statement is a great tool when
you want to compare the same variable or

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expression with many different values and

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execute different pieces of
code depending on that value.

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While you could use
multiple IF statements for

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this, the switch statement can give
you cleaner and easier to read code.

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Once again be clear and expressive
in what the code should be doing.