Creating Functions


 function function_name([$arg1 [, $arg2, ..., [$argN]]]) {     [statement]     [return $return_value;] } 

Functions are groups of statements that act together; you can call functions and pass data to them, and they can return results to you. Any valid PHP code can be placed inside a function, including other functions and PHP class definitions.

Here's an example:

 function echoer() {     echo "No worries."; } 

When called, this function echoes "No worries.". Here's how you call it from other code:

 echoer(); 

You can also pass data to functions as arguments by enclosing them inside parentheses. Here's an example that passes an array to a function, which just echoes the contents of the array:

 <?php     $vegetables[0] = "corn";     $vegetables[1] = "squash";     $vegetables[2] = "cauliflower";     $vegetables[3] = "beans";     echoer($vegetables);     function echoer($array)     {         for ($index = 0; $index < count($array); $index++){             echo "Element $index: ", $array[$index], "\n";         }     } ?> 

Here's what you'd see:

 Element 0: corn Element 1: squash Element 2: cauliflower Element 3: beans 

To return a value from a function, you use the return statement:

 return (value); 

The parentheses are optional. For instance, this function increments the value you pass to it and returns the result:

 <?php     function incrementer($value)     {         return ++$value;     } ?> 

Here's how you could call this function and handle its return value:

 <?php     echo incrementer(9);     function incrementer($value)     {         return ++$value;     } ?> 



    Spring Into PHP 5
    Spring Into PHP 5
    ISBN: 0131498622
    EAN: 2147483647
    Year: 2006
    Pages: 254

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