i want to use different objects inside the template. different objects are created on different section of the site.
currently my code is
public function notify ($template, $info)
{
ob_start();
include $template;
$content = ob_get_clean();
//... more further code
}
as you see $info parameter. i dont want to use $info inside templates, but i was to use $photo, $admin or whatever is passed to it.
which i use like
// for feed
$user->notify('email_template_feed.php', $feed);
// for new photo - i would also like to use $user inside templates
$user->notify('email_template_photo.php', $photo);
how can i do that? cant use global, because is inside function and function is getting called dynamically on different locations/sections of the site, which can further extend.
You can't.
Solution 1
Instead you could use an array and extract its values:
public function notify ($__template, array $info)
{
ob_start();
extract($info);
include $__template;
$content = ob_get_clean();
//... more further code
}
Example 1
if you call it with:
$user->notify('email_template_feed.php', array('feed' => $feed));
and inside the template email_template_feed.php:
...
<?=$feed?>
...
it will print:
...
FEED
...
Solution 2
You could also pass the name of the variable as third parameter:
public function notify ($template, $info, $name)
{
ob_start();
$$name = $info;
unset($info);
include $template;
$content = ob_get_clean();
//... more further code
}
Example 2
You could then call it via:
$user->notify('email_template_feed.php', $feed, 'feed');
Related
I need to pass a function as a parameter to another function and then call the passed function from within the function...This is probably easier for me to explain in code..I basically want to do something like this:
function ($functionToBeCalled)
{
call($functionToBeCalled,additional_params);
}
Is there a way to do that.. I am using PHP 4.3.9
Thanks!
I think you are looking for call_user_func.
An example from the PHP Manual:
<?php
function barber($type) {
echo "You wanted a $type haircut, no problem";
}
call_user_func('barber', "mushroom");
call_user_func('barber', "shave");
?>
function foo($function) {
$function(" World");
}
function bar($params) {
echo "Hello".$params;
}
$variable = 'bar';
foo($variable);
Additionally, you can do it this way. See variable functions.
In php this is very simple.
<?php
function here() {
print 'here';
}
function dynamo($name) {
$name();
}
//Will work
dynamo('here');
//Will fail
dynamo('not_here');
I know the original question asked about PHP 4.3, but now it's a few years later and I just wanted to advocate for my preferred way to do this in PHP 5.3 or higher.
PHP 5.3+ now includes support for anonymous functions (closures), so you can use some standard functional programming techniques, as in languages like JavaScript and Ruby (with a few caveats). Rewriting the call_user_func example above in "closure style" would look like this, which I find more elegant:
$barber = function($type) {
echo "You wanted a $type haircut, no problem\n";
};
$barber('mushroom');
$barber('shave');
Obviously, this doesn't buy you much in this example - the power and flexibility comes when you pass these anonymous functions to other functions (as in the original question). So you can do something like:
$barber_cost = function($quantity) {
return $quantity * 15;
};
$candy_shop_cost = function($quantity) {
return $quantity * 4.50; // It's Moonstruck chocolate, ok?
};
function get_cost($cost_fn, $quantity) {
return $cost_fn($quantity);
}
echo '3 haircuts cost $' . get_cost($barber_cost, 3) . "\n";
echo '6 candies cost $' . get_cost($candy_shop_cost, 6) . "\n";
This could be done with call_user_func, of course, but I find this syntax much clearer, especially once namespaces and member variables get involved.
One caveat: I'll be the first to admit I don't know exactly what's going on here, but you can't always call a closure contained in a member or static variable, and possibly in some other cases. But reassigning it to a local variable will allow it to be invoked. So, for example, this will give you an error:
$some_value = \SomeNamespace\SomeClass::$closure($arg1, $arg2);
But this simple workaround fixes the issue:
$the_closure = \SomeNamespace\SomeClass::$closure;
$some_value = $the_closure($arg1, $arg2);
You could also use call_user_func_array(). It allows you to pass an array of parameters as the second parameter so you don't have to know exactly how many variables you're passing.
If you need pass function with parameter as parameter, you can try this:
function foo ($param1){
return $param1;
}
function bar ($foo_function, $foo_param){
echo $foo_function($foo_param);
}
//call function bar
bar('foo', 'Hi there'); //this will print: 'Hi there'
phpfiddle example
Hope it'll be helpful...
If you want to do this inside a PHP Class, take a look at this code:
// Create a sample class
class Sample
{
// Our class displays 2 lists, one for images and one for paragraphs
function __construct( $args ) {
$images = $args['images'];
$items = $args['items'];
?>
<div>
<?php
// Display a list of images
$this->loop( $images, 'image' );
// notice how we pass the name of the function as a string
// Display a list of paragraphs
$this->loop( $items, 'content' );
// notice how we pass the name of the function as a string
?>
</div>
<?php
}
// Reuse the loop
function loop( $items, $type ) {
// if there are items
if ( $items ) {
// iterate through each one
foreach ( $items as $item ) {
// pass the current item to the function
$this->$type( $item );
// becomes $this->image
// becomes $this->content
}
}
}
// Display a single image
function image( $item ) {
?>
<img src="<?php echo $item['url']; ?>">
<?php
}
// Display a single paragraph
function content( $item ) {
?>
<p><?php echo $item; ?></p>
<?php
}
}
// Create 2 sample arrays
$images = array( 'image-1.jpg', 'image-2.jpg', 'image-3.jpg' );
$items = array( 'sample one', 'sample two', 'sample three' );
// Create a sample object to pass my arrays to Sample
$elements = { 'images' => $images, 'items' => $items }
// Create an Instance of Sample and pass the $elements as arguments
new Sample( $elements );
I am writing some PHP code that would generate HTML files from templates.
I would like, if possible, to make a function that would take any strings I feed the function with, and put that into the file. Like so:
function generator($a, $b, $c, $n...){
$filename = $a . ".html";
ob_start ();
echo $b;
echo $c;
echo $d;
echo $n...;
$buffer = ob_get_clean();
file_put_contents($a, $buffer);
}
I need this, because different pages would have different number of include files, and with this I would be able to skip making different functions for specific pages. Just an iterator, and that's it.
Thanks!
From PHP 5.6+ you can use ... to indicate a variable number of arguments:
function test (... $args)
{
foreach ($args as $arg) {
echo $arg;
}
}
test("testing", "variable"); // testing variable
Demo
Variable-length argument lists from the manual
So, your function would look something like this:
function generator($a, $b, $c, ... $n) {
$filename = $a . ".html";
ob_start();
echo $b;
echo $c;
foreach ($n as $var) {
echo $var;
}
$buffer = ob_get_clean();
file_put_contents($a, $buffer);
}
You can also use variadic functions (PHP 5.6+) :
function generator($a, ...$args) {
echo $a . "\n";
print_r($args);
}
generator("test", 1, 2, 3, 4);
Outputs :
"test"
Array
(
[0] => 1
[1] => 2
[2] => 3
[3] => 4
)
You can make it using an array as following :
function generator($array){
// set the first item of the array as name of the .html file and take it out of the array.
$filename = array_shift($array) . ".html";
ob_start ();
// echo all the array fields
foreach($array as $a){
echo $a;
}
$buffer = ob_get_clean();
file_put_contents($a, $buffer);
}
You can pass the array directly to call the function like the following :
generator( ["val_1", "val_2", "val_3"] );
Just use func_get_args(); inside your function to return an array of all arguments passed in.
You can also use func_get_arg($arg_num) to return a specific argument, or func_num_args to return the number of arguments.
All PHP functions allow any number of parameters, they just won't be callable by name, the only way is with these 3 functions.
Note, you may use a variadic argument as the last in the parameter list like so:
function my_func($x,$y, ... $z){
//Now $z is an array of all arguments after the first two
}
In the process of good design, I would think carefully about when and where to use things such as this. For example I currently work on a project that probably has over 200K lines of code and for better of worse this is actually never used.
The most common way is to pass an array "struct" to the method:
$args = array();
$args['kitchen'] = 'sink';
$args['bath'] = 'room';
$args['cat'] = array('fur','tail');
$func->someFunction($args);
If you wanted to have more control over the data you could create a struct and access that within the class. Public functions act as handlers.
class SomeClass {
....
private $args
public function setArgs($arg1,$arg2,$arg3) {
$this->arg1 = $arg1;
...
}
public function getArgs() {
return $this->args;
}
More rarely you can have C++ like control where you use a class just as a struct:
class MyStruct {
public $foo;
public $bar;
private $secret;
private function getSecret() {
return $secret;
}
protect function setSecret($val) {
$secret = $val;
}
}
Already mentioned is '...' which I nearly never see but it's interesting, though how useful ? Does this help explain what is going on?
function someFunction(... $args)
Usually you will see a mix of things in methods which helps articulate the purpose of it.
private function someSmallFunc($list = array(), $val = '', $limit = 10)
This example is to illustrate the natural grouping of information, data is in a list, $val is used for something to control the method along with $limit say limits the number of query results. Hence, you should think in this way about your methods IMO.
Also if you notice default values are set ($limit = 10) to in case they aren't passed in. For example if you call someSmallFunc($data, $someVal) (opposed to say someSmallFunc($data, $someVal, 20) ) and not pass in $limit it will default to 10.
I was coding a TemplateView Class which is replacing #somevariable# placeholders with it's controller set correspondent. ViewHelpers are called via placeholders that simulate a function like #headerFiles()# for example.
The thing missing is a foreach loop definition like for example the smarty
{foreach from=$var key=index item=value} definition.
Until now I was iterating over a database object inside the controller and having a heredok or string concatenation assigned to the view. So there is a lot of html inside the controllers which I think should not be the controllers job.
I already implemented smarty into the app for testing and it's working fine - But when I decide to really use it I would have to change so many things like all partial templates would have to be .tpl files and all template directories would have to be merged ? or in one place and so on.
So my question is:
Are there any good examples or codesnippets I could use to implement a custom foreach loop method ? Before I have to change everything to use smarty. I also want to avoid using plain php like <?php foreach(): endforeach; ?>
UPDATE:
what concerns would one have going this direction ?
In a template:
#foreach array#
if($key !== 'fart'){
echo $val;
}
#endforeach#
class Foreacher {
private $template;
protected $array = array('fart' => 'poop', 'foo', 'bar');
public function __construct($template){
$this->template = file_get_contents($template);
}
public function parse(){
if(preg_match_all('/#foreach ([\w]+)#(.*?)#endforeach#/is', $this->template, $matches, PREG_SET_ORDER)){
$var = $matches[0][1];
$freach = "<?php foreach(\$this->$var as \$key => \$val){";
$freach .= $matches[0][2];
$freach .= "} ?>";
$parsed = str_replace($matches[0][0], $freach, $this->template);
$this->render($parsed);
}
}
public function __get($var){
if(isset($this->$var)){
return $this->$var;
}
return null;
}
protected function render($string){
$tmp = tmpfile();
fwrite($tmp, $string);
fseek($tmp, 0);
ob_start();
$file = stream_get_meta_data($tmp);
include $file['uri'];
$data = ob_get_clean();
fclose($tmp);
echo $data;
}
}
I have a function in one of my views, and I want to access one of the variables available to the view through CodeIgniter's data array.
For example; in my controller I have this:
$this->load->view('someview', array(
'info' => 'some info'
));
Now, within my view, I have a function, and I want to be able to access the variable $info from within that function scope.
Is that possible?
in your controller:
$GLOBALS['var_available_in_function'] = $value;
Your function:
function get_var() {
global $var_available_in_function;
return $var_available_in_function;
}
I tried this but using globals in my view someview.php doesn't work..
function func_in_view(){
global $info;
print_r ($info); // NULL
}
You may need to pass this as a parameter instead to your function so it's available to it.
function func_in_view($info){
print_r ($info); // NULL
}
I read this method $this->load->vars($array)
in http://codeigniter.com/user_guide/libraries/loader.html
but it's purpose is just to make it available to any view file from any function for that controller. I tried my code above global $info; and it still doesn't work.
You may need to do the workaround by passing it as a parameter instead.
Try including this in your someview.php => print "<pre>";print_r($GLOBALS);print "</pre>"; and the variables passed through $this->load->view aren't included.
I solved this by creating a global variable within the view, then assigning the passed in $data value to the global variable. That way, the information can be read within the view's function without having to pass the variable to the function.
For example, in the controller, you have:
$data['variable1'] = "hello world";
$this->load->view('showpage',$data);
Then in the showpage.php view, you have:
global $local_variable = $variable1;
function view_function() {
global $local_variable;
echo $local_variable;
}
view_function();
Hope this helps!
I'm sure there's a very easy explanation for this. What is the difference between this:
function barber($type){
echo "You wanted a $type haircut, no problem\n";
}
call_user_func('barber', "mushroom");
call_user_func('barber', "shave");
... and this (and what are the benefits?):
function barber($type){
echo "You wanted a $type haircut, no problem\n";
}
barber('mushroom');
barber('shave');
Always use the actual function name when you know it.
call_user_func is for calling functions whose name you don't know ahead of time but it is much less efficient since the program has to lookup the function at runtime.
Although you can call variable function names this way:
function printIt($str) { print($str); }
$funcname = 'printIt';
$funcname('Hello world!');
there are cases where you don't know how many arguments you're passing. Consider the following:
function someFunc() {
$args = func_get_args();
// do something
}
call_user_func_array('someFunc',array('one','two','three'));
It's also handy for calling static and object methods, respectively:
call_user_func(array('someClass','someFunc'),$arg);
call_user_func(array($myObj,'someFunc'),$arg);
the call_user_func option is there so you can do things like:
$dynamicFunctionName = "barber";
call_user_func($dynamicFunctionName, 'mushroom');
where the dynamicFunctionName string could be more exciting and generated at run-time. You shouldn't use call_user_func unless you have to, because it is slower.
With PHP 7 you can use the nicer variable-function syntax everywhere. It works with static/instance functions, and it can take an array of parameters. More info at https://trowski.com/2015/06/20/php-callable-paradox
$ret = $callable(...$params);
I imagine it is useful for calling a function that you don't know the name of in advance...
Something like:
switch($value):
{
case 7:
$func = 'run';
break;
default:
$func = 'stop';
break;
}
call_user_func($func, 'stuff');
There are no benefits to call it like that, the word user mean it is for multiple user, it is useful to create modification without editing in core engine.
it used by wordpress to call user function in plugins
<?php
/* main.php */
require("core.php");
require("my_plugin.php");
the_content(); // "Hello I live in Tasikmalaya"
...
<?php
/* core.php */
$listFunc = array();
$content = "Hello I live in ###";
function add_filter($fName, $funct)
{
global $listFunc;
$listFunc[$fName] = $funct;
}
function apply_filter($funct, $content)
{
global $listFunc;
foreach ($listFunc as $key => $value)
{
if ($key == $funct and is_callable($listFunc[$key]))
{
$content = call_user_func($listFunc[$key], $content);
}
}
echo $content;
}
function the_content()
{
global $content;
$content = apply_filter('the_content', $content);
echo $content;
}
....
<?php
/* my_plugin.php */
function changeMyLocation($content){
return str_replace('###', 'Tasikmalaya', $content);
}
add_filter('the_content', 'changeMyLocation');
in your first example you're using function name which is a string. it might come from outside or be determined on the fly. that is, you don't know what function will need to be run at the moment of the code creation.
When using namespaces, call_user_func() is the only way to run a function you don't know the name of beforehand, for example:
$function = '\Utilities\SearchTools::getCurrency';
call_user_func($function,'USA');
If all your functions were in the same namespace, then it wouldn't be such an issue, as you could use something like this:
$function = 'getCurrency';
$function('USA');
Edit:
Following #Jannis saying that I'm wrong I did a little more testing, and wasn't having much luck:
<?php
namespace Foo {
class Bar {
public static function getBar() {
return 'Bar';
}
}
echo "<h1>Bar: ".\Foo\Bar::getBar()."</h1>";
// outputs 'Bar: Bar'
$function = '\Foo\Bar::getBar';
echo "<h1>Bar: ".$function()."</h1>";
// outputs 'Fatal error: Call to undefined function \Foo\Bar::getBar()'
$function = '\Foo\Bar\getBar';
echo "<h1>Bar: ".$function()."</h1>";
// outputs 'Fatal error: Call to undefined function \foo\Bar\getBar()'
}
You can see the output results here: https://3v4l.org/iBERh it seems the second method works for PHP 7 onwards, but not PHP 5.6.