Functions

 

Functions can be placed anywhere, not necessarily BEFORE their call

 

function name($arguments){

statement;

}

 

 

 

function say_hello(){

echo "Hello World!<br />";

}

say_hello();

 

Hello World!

 

 

function say_hello2($word){

echo "Hello {$word}!<br />";

}

say_hello2("World");

say_hello2("Everyone");

 

 

Hello World!

Hello Everyone!

 

 

function add_subt($val1, $val2){

$add = $val1 + $val2;

$subt = $val1 - $val2;

$result = array($add, $subt);

return $result;

 

echo "Calling 'add_subt' <br />";

$result_array = add_subt(10,5);

echo "Add: " . $result_array[0] . "<br />";

echo "Substract: " . $result_array[1];

 

 

Sum is: 7
Result is: 7Calling 'add_subt'Add: 15
Substract: 5

 

Globals

 

// global by default

$bar = “Outside”;

 

function foo(){

$bar_local = "local variable";

global $bar;

$bar = "Inside";

return $var;

}

 

// pull local variable into a global one

$bar = foo($bar);

 

 

Default Values

 

function paint($color="red"){

echo "Painting with color: " . $color . "<br />";

}

 

echo "Calling 'paint()' <br />";

paint();

echo "Calling 'paint(blue)' <br />";

paint("blue");

 

Calling 'paint()'
Painting with color: red
Calling 'paint(blue)'
Painting with color: blue