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@NogDogJul 05.2009 — #It is usually better to pass variables as function parameters rather than using global variables, as the latter make for tightly coupled code that is difficult to debug or re-use. If desired, you could pass by reference if you want the function to affect a variable without having to return() it. (Also, defining a function within a function can be a problem if the outer function gets called more than once -- causing a duplicate function name error -- so is generally best avoided.)
@NogDogJul 05.2009 — #PS: It should probably be noted at this point that an object-oriented approach may be better suited to organizing the interrelationship between data and functions, depending on what it is you really need to do:
@NogDogJul 05.2009 — #You could do it by declaring the variable as global within [i]both[/i] functions, but this risks collisions with the same variable name outside of the functions, along with all the other baggage that comes with the use of globals within functions (and is in general [i]not[/i] the way I would ever recommend doing this).
Vairable scope in functions
Hi,
How can I access a variable in a function in another function?
for example :
[CODE]
<?php
$a = 2;
function test1()
{
global $a; // This access the $a
$b = 3; // A variable that is being defined in this function
function test2()
{
global $a; // This access the $a also
global $b; // This DOES NOT ACCESS $b
}
}
?>
How can I access the $b [b]without
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@NogDogJul 05.2009 — #It is usually better to pass variables as function parameters rather than using global variables, as the latter make for tightly coupled code that is difficult to debug or re-use. If desired, you could pass by reference if you want the function to affect a variable without having to return() it. (Also, defining a function within a function can be a problem if the outer function gets called more than once -- causing a duplicate function name error -- so is generally best avoided.)[code=php]
<?php
function test1(&$a) // pass by reference
{
$b = 3; // A variable that is being defined in this function
test2($a, $b);
}
function test2(&$a, $b)
{
$a += $b;
}
$foo = 2;
test1($foo);
echo $foo; // 5
?>
[/code]0
@NogDogJul 05.2009 — #PS: It should probably be noted at this point that an object-oriented approach may be better suited to organizing the interrelationship between data and functions, depending on what it is you really need to do:[code=php]
<?php
class Example
{
private $foo;
private $bar;
public function __construct($foo)
{
$this->foo = $foo;
}
public function getFoo()
{
return $this->foo;
}
public function test1()
{
$this->bar = 3;
$this->test2();
}
private function test2()
{
$this->foo += $this->bar;
}
}
$test = new Example(2);
$test->test1();
echo $test->getFoo(); // 5
?>
[/code]0
@NogDogJul 05.2009 — #You could do it by declaring the variable as global within [i]both[/i] functions, but this risks collisions with the same variable name outside of the functions, along with all the other baggage that comes with the use of globals within functions (and is in general [i]not[/i] the way I would ever recommend doing this).[code=php]
<?php
function test1()
{
global $a, $b;
if(!function_exists('test2'))
{
function test2()
{
global $a, $b;
$a += $b;
}
}
$b = 3;
test2();
}
$a = 2;
test1();
echo $a; // 5
?>
[/code]