The switch Statement

switch is the older way to compare one value against many options. You will see it a lot in existing code, so you should know how it works.

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<?php
$day = "Tue";

switch ($day) {
    case "Mon":
        echo "Start of the week";
        break;
    case "Tue":
    case "Wed":
        echo "Midweek";
        break;
    case "Sat":
    case "Sun":
        echo "Weekend";
        break;
    default:
        echo "Another day";
}

1

Midweek

The break statement

Each case needs a break. Without it, PHP keeps running the next case’s code too. That is called fall-through.

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<?php
$n = 1;

switch ($n) {
    case 1:
        echo "one ";
    case 2:
        echo "two ";
        break;
    case 3:
        echo "three";
}

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one two

case 1 had no break, so PHP ran into case 2. Sometimes this is intended (like "Tue" and "Wed" above), but it is a common source of bugs.

The default case

default runs when no case matches. It is optional, and usually goes last.

Loose comparison

switch compares with ==, not ===. Strings that look like numbers can match unexpectedly.

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<?php
$input = "1";

switch ($input) {
    case 1:
        echo "matched the integer 1";
        break;
    default:
        echo "no match";
}

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matched the integer 1

switch vs match

When switch is still the right tool

Use switch when each branch needs several statements, or when you work on PHP 7. Otherwise match is safer.