Related
Is it possible to have a function with two returns like this:
function test($testvar)
{
// Do something
return $var1;
return $var2;
}
If so, how would I be able to get each return separately?
Technically, you can't return more than one value. However, there are multiple ways to work around that limitation. The way that acts most like returning multiple values, is with the list keyword:
function getXYZ()
{
return array(4,5,6);
}
list($x,$y,$z) = getXYZ();
// Afterwards: $x == 4 && $y == 5 && $z == 6
// (This will hold for all samples unless otherwise noted)
Technically, you're returning an array and using list to store the elements of that array in different values instead of storing the actual array. Using this technique will make it feel most like returning multiple values.
The list solution is a rather php-specific one. There are a few languages with similar structures, but more languages that don't. There's another way that's commonly used to "return" multiple values and it's available in just about every language (in one way or another). However, this method will look quite different so may need some getting used to.
// note that I named the arguments $a, $b and $c to show that
// they don't need to be named $x, $y and $z
function getXYZ(&$a, &$b, &$c)
{
$a = 4;
$b = 5;
$c = 6;
}
getXYZ($x, $y, $z);
This technique is also used in some functions defined by php itself (e.g. $count in str_replace, $matches in preg_match). This might feel quite different from returning multiple values, but it is worth at least knowing about.
A third method is to use an object to hold the different values you need. This is more typing, so it's not used quite as often as the two methods above. It may make sense to use this, though, when using the same set of variables in a number of places (or of course, working in a language that doesn't support the above methods or allows you to do this without extra typing).
class MyXYZ
{
public $x;
public $y;
public $z;
}
function getXYZ()
{
$out = new MyXYZ();
$out->x = 4;
$out->y = 5;
$out->z = 6;
return $out;
}
$xyz = getXYZ();
$x = $xyz->x;
$y = $xyz->y;
$z = $xyz->z;
The above methods sum up the main ways of returning multiple values from a function. However, there are variations on these methods. The most interesting variations to look at, are those in which you are actually returning an array, simply because there's so much you can do with arrays in PHP.
First, we can simply return an array and not treat it as anything but an array:
function getXYZ()
{
return array(1,2,3);
}
$array = getXYZ();
$x = $array[0];
$y = $array[1];
$z = $array[2];
The most interesting part about the code above is that the code inside the function is the same as in the very first example I provided; only the code calling the function changed. This means that it's up to the one calling the function how to treat the result the function returns.
Alternatively, one could use an associative array:
function getXYZ()
{
return array('x' => 4,
'y' => 5,
'z' => 6);
}
$array = getXYZ();
$x = $array['x'];
$y = $array['y'];
$z = $array['z'];
Php does have the compact function that allows you to do same as above but while writing less code. (Well, the sample won't have less code, but a real world application probably would.) However, I think the amount of typing saving is minimal and it makes the code harder to read, so I wouldn't do it myself. Nevertheless, here's a sample:
function getXYZ()
{
$x = 4;
$y = 5;
$z = 6;
return compact('x', 'y', 'z');
}
$array = getXYZ();
$x = $array['x'];
$y = $array['y'];
$z = $array['z'];
It should be noted that while compact does have a counterpart in extract that could be used in the calling code here, but since it's a bad idea to use it (especially for something as simple as this) I won't even give a sample for it. The problem is that it will do "magic" and create variables for you, while you can't see which variables are created without going to other parts of the code.
Finally, I would like to mention that list doesn't really play well with associative array. The following will do what you expect:
function getXYZ()
{
return array('x' => 4,
'y' => 5,
'z' => 6);
}
$array = getXYZ();
list($x, $y, $z) = getXYZ();
However, the following will do something different:
function getXYZ()
{
return array('x' => 4,
'z' => 6,
'y' => 5);
}
$array = getXYZ();
list($x, $y, $z) = getXYZ();
// Pay attention: $y == 6 && $z == 5
If you used list with an associative array, and someone else has to change the code in the called function in the future (which may happen just about any situation) it may suddenly break, so I would recommend against combining list with associative arrays.
There is no way of returning 2 variables. Although, you can propagate an array and return it; create a conditional to return a dynamic variable, etc.
For instance, this function would return $var2
function wtf($blahblah = true) {
$var1 = "ONe";
$var2 = "tWo";
if($blahblah === true) {
return $var2;
}
return $var1;
}
In application:
echo wtf();
//would echo: tWo
echo wtf("not true, this is false");
//would echo: ONe
If you wanted them both, you could modify the function a bit
function wtf($blahblah = true) {
$var1 = "ONe";
$var2 = "tWo";
if($blahblah === true) {
return $var2;
}
if($blahblah == "both") {
return array($var1, $var2);
}
return $var1;
}
echo wtf("both")[0]
//would echo: ONe
echo wtf("both")[1]
//would echo: tWo
list($first, $second) = wtf("both")
// value of $first would be $var1, value of $second would be $var2
In your example, the second return will never happen - the first return is the last thing PHP will run. If you need to return multiple values, return an array:
function test($testvar) {
return array($var1, $var2);
}
$result = test($testvar);
echo $result[0]; // $var1
echo $result[1]; // $var2
Since PHP 7.1 we have proper destructuring for lists.
Thereby you can do things like this:
$test = [1, 2, 3, 4];
[$a, $b, $c, $d] = $test;
echo($a);
> 1
echo($d);
> 4
In a function this would look like this:
function multiple_return() {
return ['this', 'is', 'a', 'test'];
}
[$first, $second, $third, $fourth] = multiple_return();
echo($first);
> this
echo($fourth);
> test
Destructuring is a very powerful tool. It's capable of destructuring key=>value pairs as well:
["a" => $a, "b" => $b, "c" => $c] = ["a" => 1, "b" => 2, "c" => 3];
Take a look at the new feature page for PHP 7.1:
New features
In PHP 5.5 there is also a new concept: generators, where you can yield multiple values from a function:
function hasMultipleValues() {
yield "value1";
yield "value2";
}
$values = hasMultipleValues();
foreach ($values as $val) {
// $val will first be "value1" then "value2"
}
Or you can pass by reference:
function byRef($x, &$a, &$b)
{
$a = 10 * $x;
$b = 100 * $x;
}
$a = 0;
$b = 0;
byRef(10, $a, $b);
echo $a . "\n";
echo $b;
This would output
100
1000
For PHP 7.1.0 onwards, you can use the new syntax (instead of the list function):
/**
* #return array [foo, bar]
*/
function getFooAndBar(): array {
return ['foo', 'bar'];
}
[$foo, $bar] = getFooAndBar();
print 'Hello '. $foo . ' and ' . $bar;
It's OK for me if you want to return 2-3 variables, otherwise you should use an object with the desired properties.
I know that I am pretty late, but there is a nice and simple solution for this problem.
It's possible to return multiple values at once using destructuring.
function test()
{
return [ 'model' => 'someValue' , 'data' => 'someothervalue'];
}
Now you can use this
$result = test();
extract($result);
extract creates a variable for each member in the array, named after that member. You can therefore now access $model and $data
You can return multiple arrays and scalars from a function
function x()
{
$a=array("a","b","c");
$b=array("e","f");
return array('x',$a,$b);
}
list ($m,$n,$o)=x();
echo $m."\n";
print_r($n);
print_r($o);
Its not possible have two return statement. However it doesn't throw error but when function is called you will receive only first return statement value.
We can use return of array to get multiple values in return. For Example:
function test($testvar)
{
// do something
//just assigning a string for example, we can assign any operation result
$var1 = "result1";
$var2 = "result2";
return array('value1' => $var1, 'value2' => $var2);
}
Best Practice is to put your returned variables into array and then use list() to assign array values to variables.
<?php
function add_subt($val1, $val2) {
$add = $val1 + $val2;
$subt = $val1 - $val2;
return array($add, $subt);
}
list($add_result, $subt_result) = add_subt(20, 7);
echo "Add: " . $add_result . '<br />';
echo "Subtract: " . $subt_result . '<br />';
?>
Functions, by definition, only return one value.
However, as you assumed, that value can be an array.
So you can certainly do something like:
<?PHP
function myfunc($a,$b){
return array('foo'=>$a,'bar'=>$b);
}
print_r(myfunc('baz','bork'));
That said, it's worth taking a moment and thinking about whatever you're trying to solve. While returning a complex result value (like an array, or an object) is perfectly valid, if you're thinking is that "I want to return two values", you might be designing poorly. Without more detail in your question, it's hard to say, but it never hurts to stop and think twice.
The answer that's given the green tick above is actually incorrect. You can return multiple values in PHP, if you return an array. See the following code for an example:
<?php
function small_numbers()
{
return array (0, 1, 2);
}
list ($zero, $one, $two) = small_numbers();
This code is actually copied from the following page on PHP's website: http://php.net/manual/en/functions.returning-values.php
I've also used the same sort of code many times myself, so can confirm that it's good and that it works.
Yes, you can use an object :-)
But the simplest way is to return an array:
return array('value1', 'value2', 'value3', '...');
I have implement like this for multiple return value PHP function. be nice with your code. thank you.
<?php
function multi_retun($aa)
{
return array(1,3,$aa);
}
list($one,$two,$three)=multi_retun(55);
echo $one;
echo $two;
echo $three;
?>
PHP 7.1 Update
Return an array.
function test($testvar)
{
// Do something
return [$var1, $var2];
}
then use that like below:
[$value1, $value2] = test($testvar);
Functions in PHP can return only one variable. you could use variables with global scope, you can return array, or you can pass variable by reference to the function and than change value,.. but all of that will decrease readability of your code.
I would suggest that you look into the classes.
Thought I would expand on a few of the responses from above....
class nameCheck{
public $name;
public function __construct(){
$this->name = $name;
}
function firstName(){
// If a name has been entered..
if(!empty($this->name)){
$name = $this->name;
$errflag = false;
// Return a array with both the name and errflag
return array($name, $errflag);
// If its empty..
}else if(empty($this->name)){
$errmsg = 'Please enter a name.';
$errflag = true;
// Return both the Error message and Flag
return array($errmsg, $errflag);
}
}
}
if($_POST['submit']){
$a = new nameCheck;
$a->name = $_POST['name'];
// Assign a list of variables from the firstName function
list($name, $err) = $a->firstName();
// Display the values..
echo 'Name: ' . $name;
echo 'Errflag: ' . $err;
}
?>
<form method="post" action="<?php $_SERVER['PHP_SELF']; ?>" >
<input name="name" />
<input type="submit" name="submit" value="submit" />
</form>
This will give you a input field and a submit button once submitted, if the name input field is empty it will return the error flag and a message. If the name field has a value it will return the value/name and a error flag of 0 for false = no errors.
Hope this helps!
Some might prefer returning multiple values as object:
function test() {
$object = new stdClass();
$object->x = 'value 1';
$object->y = 'value 2';
return $object;
}
And call it like this:
echo test()->x;
Or:
$test = test();
echo $test->y;
Yes and no. You can't return more than one variable / object, but as you suggest, you can put them into an array and return that.
There is no limit to the nesting of arrays, so you can just package them up that way to return.
You can always only return one variable which might be an array. But You can change global variables from inside the function. That is most of the time not very good style, but it works. In classes you usually change class varbiables from within functions without returning them.
The answer is no. When the parser reaches the first return statement, it will direct control back to the calling function - your second return statement will never be executed.
Add all variables in an array and then finally return the array.
function test($testvar)
{
// do something
return array("var1" => $var1, "var2" => #var2);
}
And then
$myTest = test($myTestVar);
//$myTest["var1"] and $myTest["var2"] will be usable
I think eliego has explained the answer clearly. But if you want to return both values, put them into a array and return it.
function test($testvar)
{
// do something
return array('var1'=>$var1,'var2'=>$var2);
//defining a key would be better some times
}
//to access return values
$returned_values = test($testvar);
echo $returned_values['var1'];
echo $returned_values['var2'];
<?php
function foo(){
$you = 5;
$me = 10;
return $you;
return $me;
}
echo foo();
//output is just 5 alone so we cant get second one it only retuns first one so better go with array
function goo(){
$you = 5;
$me = 10;
return $you_and_me = array($you,$me);
}
var_dump(goo()); // var_dump result is array(2) { [0]=> int(5) [1]=> int(10) } i think thats fine enough
?>
Languages which allow multiple returns usually just convert the multiple values into a data structure.
For example, in Python you can return multiple values. However, they're actually just being returned as one tuple.
So you can return multiple values in PHP by just creating a simple array and returning that.
You can get the values of two or more variables by setting them by reference:
function t(&$a, &$b) {
$a = 1;
$b = 2;
}
t($a, $b);
echo $a . ' ' . $b;
Output:
1 2
Does PHP still use "out parameters"? If so, you can use the syntax to modify one or more of the parameters going in to your function then. You would then be free to use the modified variable after your function returns.
$var1 = 0;
$var2 = 0;
function test($testvar, &$var1 , &$var2)
{
$var1 = 1;
$var2 = 2;
return;
}
test("", $var1, $var2);
// var1 = 1, var2 = 2
It's not a good way, but I think we can set two variables in a function at the same time.
This is the easiest way to do it:
public function selectAllUsersByRole($userRole, $selector) {
$this->userRole = $userLevel;
$this->selector = $selector;
$sql = "SELECT * FROM users WHERE role <= ? AND del_stat = 0";
$stm = $this->connect()->prepare($sql); // Connect function in Dbh connect to database file
$stm->execute([$this->userRole]); // This is PHP 7. Use array($this->userRole) for PHP 5
$usersIdArray = array();
$usersFNameArray = array();
$usersLNameArray = array();
if($stm->rowCount()) {
while($row = $stm->fetch()) {
array_push($usersIdArray, $row['id']);
array_push($usersFNameArray, $row['f_name']);
array_push($usersLNameArray, $row['l_name']);
// You can return only $row['id'] or f_name or ...
// I used the array because it's most used.
}
}
if($this->selector == 1) {
return $usersIdArray;
}elseif($this->selector == 2) {
return $usersFNameArray;
}elseif($this->selector == 3) {
return $usersLNameArray;
}
}
How can we call this function?
$idData = $selectAllUsers->selectAllUsersByLevel($userRole, 0);
print_r($idData);
$idFName = $selectAllUsers->selectAllUsersByLevel($userRole, 1);
print_r($idFname);
That's it. Very easy.
I am using a recursive function in php. The function travers through an array and inputs some values of the array in a new array. I am using array_push() to enter values in the new array and I have also tried to do it without using array_push. This is the part of the function that calls the recursive function
if ($this->input->post('id') != '') {
$id = $this->input->post('id');
global $array_ins;
$k=0;
$data['condition_array'] = $this->array_check($id, $menus['parents'], $k);
// trial
echo "<pre>";
print_r($menus['parents']);
print_r($data['condition_array']);die;
// trial
}
and this here is the recursive function
function array_check($val, $array_main, $k) {
// echo $val . "<br>";
$array_ins[$k] = $val;
echo $k . "<br>";
$k++;
// $array_ins = array_push($array_ins, $val);
echo "<pre>";
print_r($array_ins);
if ($array_main[$val] != '') {
for ($i = 0; $i < sizeof($array_main[$val]); $i++) {
$this->array_check($array_main[$val][$i], $array_main, $k);
}
// $k++;
}
I've been trying to fix this erorr for quite some time with no luck . I would really appreciate any help possible .
thanks in advance
Move the global $array_ins; statement into the function.
Pass the variable $array_ins as a parameter to function
function array_check($val, $array_main, $k,$array_ins) {
}
and call the function
$this->array_check($id, $menus['parents'], $k,$array_ins);
or
function array_check($val, $array_main, $k) {
global $array_ins;
}
usage of global is not recommended in php check it here Are global variables in PHP considered bad practice? If so, why?
The global keyword should be used inside of functions so that the variable will refer to the value in the outer scope.
<?php
$a = 1;
$b = 2;
function Sum()
{
global $a, $b;
$b = $a + $b;
}
Sum();
echo $b; // 3
I use PHP (with KirbyCMS) and can create this code:
$results = $site->filterBy('a_key', 'a_value')->filterBy('a_key2', 'a_value2');
This is a chain with two filterBy. It works.
However I need to build a function call like this dynamically. Sometimes it can be two chained function calls, sometimes three or more.
How is that done?
Maybe you can play with this code?
chain is just a random number that can be used to create between 1-5 chains.
for( $i = 0; $i < 10; $i ++ ) {
$chains = rand(1, 5);
}
Examples of desired result
Example one, just one function call
$results = $site->filterBy('a_key', 'a_value');
Example two, many nested function calls
$results = $site->filterBy('a_key', 'a_value')->filterBy('a_key2', 'a_value2')->filterBy('a_key3', 'a_value3')->filterBy('a_key4', 'a_value4')->filterBy('a_key5', 'a_value5')->filterBy('a_key6', 'a_value6');
$chains = rand(1, 5)
$results = $site
$suffix = ''
for ( $i = 1; $i <= $chains; $i ++) {
if ($i != 1) {
$suffix = $i
}
$results = $results->filterBy('a_key' . $suffix, 'a_value' . $suffix)
}
If you are able to pass 'a_key1' and 'a_value1' to the first call to filterBy instead of 'a_key' and 'a_value', you could simplify the code by removing $suffix and the if block and just appending $i.
You don't need to generate the list of chained calls. You can put the arguments of each call in a list then write a new method of the class that gets them from the list and uses them to invoke filterBy() repeatedly.
I assume from your example code that function filterBy() returns $this or another object of the same class as site.
//
// The code that generates the filtering parameters:
// Store the arguments of the filtering here
$params = array();
// Put as many sets of arguments you need
// use whatever method suits you best to produce them
$params[] = array('key1', 'value1');
$params[] = array('key2', 'value2');
$params[] = array('key3', 'value3');
//
// Do the multiple filtering
$site = new Site();
$result = $site->filterByMultiple($params);
//
// The code that does the actual filtering
class Site {
public function filterByMultiple(array $params) {
$result = $this;
foreach ($params as list($key, $value)) {
$result = $result->filterBy($key, $value);
}
return $result;
}
}
If filterBy() returns $this then you don't need the working variable $result; call $this->filterBy() and return $this; and remove the other occurrences of $result.
Is it possible to have a function with two returns like this:
function test($testvar)
{
// Do something
return $var1;
return $var2;
}
If so, how would I be able to get each return separately?
Technically, you can't return more than one value. However, there are multiple ways to work around that limitation. The way that acts most like returning multiple values, is with the list keyword:
function getXYZ()
{
return array(4,5,6);
}
list($x,$y,$z) = getXYZ();
// Afterwards: $x == 4 && $y == 5 && $z == 6
// (This will hold for all samples unless otherwise noted)
Technically, you're returning an array and using list to store the elements of that array in different values instead of storing the actual array. Using this technique will make it feel most like returning multiple values.
The list solution is a rather php-specific one. There are a few languages with similar structures, but more languages that don't. There's another way that's commonly used to "return" multiple values and it's available in just about every language (in one way or another). However, this method will look quite different so may need some getting used to.
// note that I named the arguments $a, $b and $c to show that
// they don't need to be named $x, $y and $z
function getXYZ(&$a, &$b, &$c)
{
$a = 4;
$b = 5;
$c = 6;
}
getXYZ($x, $y, $z);
This technique is also used in some functions defined by php itself (e.g. $count in str_replace, $matches in preg_match). This might feel quite different from returning multiple values, but it is worth at least knowing about.
A third method is to use an object to hold the different values you need. This is more typing, so it's not used quite as often as the two methods above. It may make sense to use this, though, when using the same set of variables in a number of places (or of course, working in a language that doesn't support the above methods or allows you to do this without extra typing).
class MyXYZ
{
public $x;
public $y;
public $z;
}
function getXYZ()
{
$out = new MyXYZ();
$out->x = 4;
$out->y = 5;
$out->z = 6;
return $out;
}
$xyz = getXYZ();
$x = $xyz->x;
$y = $xyz->y;
$z = $xyz->z;
The above methods sum up the main ways of returning multiple values from a function. However, there are variations on these methods. The most interesting variations to look at, are those in which you are actually returning an array, simply because there's so much you can do with arrays in PHP.
First, we can simply return an array and not treat it as anything but an array:
function getXYZ()
{
return array(1,2,3);
}
$array = getXYZ();
$x = $array[0];
$y = $array[1];
$z = $array[2];
The most interesting part about the code above is that the code inside the function is the same as in the very first example I provided; only the code calling the function changed. This means that it's up to the one calling the function how to treat the result the function returns.
Alternatively, one could use an associative array:
function getXYZ()
{
return array('x' => 4,
'y' => 5,
'z' => 6);
}
$array = getXYZ();
$x = $array['x'];
$y = $array['y'];
$z = $array['z'];
Php does have the compact function that allows you to do same as above but while writing less code. (Well, the sample won't have less code, but a real world application probably would.) However, I think the amount of typing saving is minimal and it makes the code harder to read, so I wouldn't do it myself. Nevertheless, here's a sample:
function getXYZ()
{
$x = 4;
$y = 5;
$z = 6;
return compact('x', 'y', 'z');
}
$array = getXYZ();
$x = $array['x'];
$y = $array['y'];
$z = $array['z'];
It should be noted that while compact does have a counterpart in extract that could be used in the calling code here, but since it's a bad idea to use it (especially for something as simple as this) I won't even give a sample for it. The problem is that it will do "magic" and create variables for you, while you can't see which variables are created without going to other parts of the code.
Finally, I would like to mention that list doesn't really play well with associative array. The following will do what you expect:
function getXYZ()
{
return array('x' => 4,
'y' => 5,
'z' => 6);
}
$array = getXYZ();
list($x, $y, $z) = getXYZ();
However, the following will do something different:
function getXYZ()
{
return array('x' => 4,
'z' => 6,
'y' => 5);
}
$array = getXYZ();
list($x, $y, $z) = getXYZ();
// Pay attention: $y == 6 && $z == 5
If you used list with an associative array, and someone else has to change the code in the called function in the future (which may happen just about any situation) it may suddenly break, so I would recommend against combining list with associative arrays.
There is no way of returning 2 variables. Although, you can propagate an array and return it; create a conditional to return a dynamic variable, etc.
For instance, this function would return $var2
function wtf($blahblah = true) {
$var1 = "ONe";
$var2 = "tWo";
if($blahblah === true) {
return $var2;
}
return $var1;
}
In application:
echo wtf();
//would echo: tWo
echo wtf("not true, this is false");
//would echo: ONe
If you wanted them both, you could modify the function a bit
function wtf($blahblah = true) {
$var1 = "ONe";
$var2 = "tWo";
if($blahblah === true) {
return $var2;
}
if($blahblah == "both") {
return array($var1, $var2);
}
return $var1;
}
echo wtf("both")[0]
//would echo: ONe
echo wtf("both")[1]
//would echo: tWo
list($first, $second) = wtf("both")
// value of $first would be $var1, value of $second would be $var2
In your example, the second return will never happen - the first return is the last thing PHP will run. If you need to return multiple values, return an array:
function test($testvar) {
return array($var1, $var2);
}
$result = test($testvar);
echo $result[0]; // $var1
echo $result[1]; // $var2
Since PHP 7.1 we have proper destructuring for lists.
Thereby you can do things like this:
$test = [1, 2, 3, 4];
[$a, $b, $c, $d] = $test;
echo($a);
> 1
echo($d);
> 4
In a function this would look like this:
function multiple_return() {
return ['this', 'is', 'a', 'test'];
}
[$first, $second, $third, $fourth] = multiple_return();
echo($first);
> this
echo($fourth);
> test
Destructuring is a very powerful tool. It's capable of destructuring key=>value pairs as well:
["a" => $a, "b" => $b, "c" => $c] = ["a" => 1, "b" => 2, "c" => 3];
Take a look at the new feature page for PHP 7.1:
New features
In PHP 5.5 there is also a new concept: generators, where you can yield multiple values from a function:
function hasMultipleValues() {
yield "value1";
yield "value2";
}
$values = hasMultipleValues();
foreach ($values as $val) {
// $val will first be "value1" then "value2"
}
Or you can pass by reference:
function byRef($x, &$a, &$b)
{
$a = 10 * $x;
$b = 100 * $x;
}
$a = 0;
$b = 0;
byRef(10, $a, $b);
echo $a . "\n";
echo $b;
This would output
100
1000
For PHP 7.1.0 onwards, you can use the new syntax (instead of the list function):
/**
* #return array [foo, bar]
*/
function getFooAndBar(): array {
return ['foo', 'bar'];
}
[$foo, $bar] = getFooAndBar();
print 'Hello '. $foo . ' and ' . $bar;
It's OK for me if you want to return 2-3 variables, otherwise you should use an object with the desired properties.
I know that I am pretty late, but there is a nice and simple solution for this problem.
It's possible to return multiple values at once using destructuring.
function test()
{
return [ 'model' => 'someValue' , 'data' => 'someothervalue'];
}
Now you can use this
$result = test();
extract($result);
extract creates a variable for each member in the array, named after that member. You can therefore now access $model and $data
You can return multiple arrays and scalars from a function
function x()
{
$a=array("a","b","c");
$b=array("e","f");
return array('x',$a,$b);
}
list ($m,$n,$o)=x();
echo $m."\n";
print_r($n);
print_r($o);
Its not possible have two return statement. However it doesn't throw error but when function is called you will receive only first return statement value.
We can use return of array to get multiple values in return. For Example:
function test($testvar)
{
// do something
//just assigning a string for example, we can assign any operation result
$var1 = "result1";
$var2 = "result2";
return array('value1' => $var1, 'value2' => $var2);
}
Best Practice is to put your returned variables into array and then use list() to assign array values to variables.
<?php
function add_subt($val1, $val2) {
$add = $val1 + $val2;
$subt = $val1 - $val2;
return array($add, $subt);
}
list($add_result, $subt_result) = add_subt(20, 7);
echo "Add: " . $add_result . '<br />';
echo "Subtract: " . $subt_result . '<br />';
?>
Functions, by definition, only return one value.
However, as you assumed, that value can be an array.
So you can certainly do something like:
<?PHP
function myfunc($a,$b){
return array('foo'=>$a,'bar'=>$b);
}
print_r(myfunc('baz','bork'));
That said, it's worth taking a moment and thinking about whatever you're trying to solve. While returning a complex result value (like an array, or an object) is perfectly valid, if you're thinking is that "I want to return two values", you might be designing poorly. Without more detail in your question, it's hard to say, but it never hurts to stop and think twice.
The answer that's given the green tick above is actually incorrect. You can return multiple values in PHP, if you return an array. See the following code for an example:
<?php
function small_numbers()
{
return array (0, 1, 2);
}
list ($zero, $one, $two) = small_numbers();
This code is actually copied from the following page on PHP's website: http://php.net/manual/en/functions.returning-values.php
I've also used the same sort of code many times myself, so can confirm that it's good and that it works.
Yes, you can use an object :-)
But the simplest way is to return an array:
return array('value1', 'value2', 'value3', '...');
I have implement like this for multiple return value PHP function. be nice with your code. thank you.
<?php
function multi_retun($aa)
{
return array(1,3,$aa);
}
list($one,$two,$three)=multi_retun(55);
echo $one;
echo $two;
echo $three;
?>
PHP 7.1 Update
Return an array.
function test($testvar)
{
// Do something
return [$var1, $var2];
}
then use that like below:
[$value1, $value2] = test($testvar);
Functions in PHP can return only one variable. you could use variables with global scope, you can return array, or you can pass variable by reference to the function and than change value,.. but all of that will decrease readability of your code.
I would suggest that you look into the classes.
Thought I would expand on a few of the responses from above....
class nameCheck{
public $name;
public function __construct(){
$this->name = $name;
}
function firstName(){
// If a name has been entered..
if(!empty($this->name)){
$name = $this->name;
$errflag = false;
// Return a array with both the name and errflag
return array($name, $errflag);
// If its empty..
}else if(empty($this->name)){
$errmsg = 'Please enter a name.';
$errflag = true;
// Return both the Error message and Flag
return array($errmsg, $errflag);
}
}
}
if($_POST['submit']){
$a = new nameCheck;
$a->name = $_POST['name'];
// Assign a list of variables from the firstName function
list($name, $err) = $a->firstName();
// Display the values..
echo 'Name: ' . $name;
echo 'Errflag: ' . $err;
}
?>
<form method="post" action="<?php $_SERVER['PHP_SELF']; ?>" >
<input name="name" />
<input type="submit" name="submit" value="submit" />
</form>
This will give you a input field and a submit button once submitted, if the name input field is empty it will return the error flag and a message. If the name field has a value it will return the value/name and a error flag of 0 for false = no errors.
Hope this helps!
Some might prefer returning multiple values as object:
function test() {
$object = new stdClass();
$object->x = 'value 1';
$object->y = 'value 2';
return $object;
}
And call it like this:
echo test()->x;
Or:
$test = test();
echo $test->y;
Yes and no. You can't return more than one variable / object, but as you suggest, you can put them into an array and return that.
There is no limit to the nesting of arrays, so you can just package them up that way to return.
You can always only return one variable which might be an array. But You can change global variables from inside the function. That is most of the time not very good style, but it works. In classes you usually change class varbiables from within functions without returning them.
The answer is no. When the parser reaches the first return statement, it will direct control back to the calling function - your second return statement will never be executed.
Add all variables in an array and then finally return the array.
function test($testvar)
{
// do something
return array("var1" => $var1, "var2" => #var2);
}
And then
$myTest = test($myTestVar);
//$myTest["var1"] and $myTest["var2"] will be usable
I think eliego has explained the answer clearly. But if you want to return both values, put them into a array and return it.
function test($testvar)
{
// do something
return array('var1'=>$var1,'var2'=>$var2);
//defining a key would be better some times
}
//to access return values
$returned_values = test($testvar);
echo $returned_values['var1'];
echo $returned_values['var2'];
<?php
function foo(){
$you = 5;
$me = 10;
return $you;
return $me;
}
echo foo();
//output is just 5 alone so we cant get second one it only retuns first one so better go with array
function goo(){
$you = 5;
$me = 10;
return $you_and_me = array($you,$me);
}
var_dump(goo()); // var_dump result is array(2) { [0]=> int(5) [1]=> int(10) } i think thats fine enough
?>
Languages which allow multiple returns usually just convert the multiple values into a data structure.
For example, in Python you can return multiple values. However, they're actually just being returned as one tuple.
So you can return multiple values in PHP by just creating a simple array and returning that.
You can get the values of two or more variables by setting them by reference:
function t(&$a, &$b) {
$a = 1;
$b = 2;
}
t($a, $b);
echo $a . ' ' . $b;
Output:
1 2
Does PHP still use "out parameters"? If so, you can use the syntax to modify one or more of the parameters going in to your function then. You would then be free to use the modified variable after your function returns.
$var1 = 0;
$var2 = 0;
function test($testvar, &$var1 , &$var2)
{
$var1 = 1;
$var2 = 2;
return;
}
test("", $var1, $var2);
// var1 = 1, var2 = 2
It's not a good way, but I think we can set two variables in a function at the same time.
This is the easiest way to do it:
public function selectAllUsersByRole($userRole, $selector) {
$this->userRole = $userLevel;
$this->selector = $selector;
$sql = "SELECT * FROM users WHERE role <= ? AND del_stat = 0";
$stm = $this->connect()->prepare($sql); // Connect function in Dbh connect to database file
$stm->execute([$this->userRole]); // This is PHP 7. Use array($this->userRole) for PHP 5
$usersIdArray = array();
$usersFNameArray = array();
$usersLNameArray = array();
if($stm->rowCount()) {
while($row = $stm->fetch()) {
array_push($usersIdArray, $row['id']);
array_push($usersFNameArray, $row['f_name']);
array_push($usersLNameArray, $row['l_name']);
// You can return only $row['id'] or f_name or ...
// I used the array because it's most used.
}
}
if($this->selector == 1) {
return $usersIdArray;
}elseif($this->selector == 2) {
return $usersFNameArray;
}elseif($this->selector == 3) {
return $usersLNameArray;
}
}
How can we call this function?
$idData = $selectAllUsers->selectAllUsersByLevel($userRole, 0);
print_r($idData);
$idFName = $selectAllUsers->selectAllUsersByLevel($userRole, 1);
print_r($idFname);
That's it. Very easy.
I have the following PHP code which works out the possible combinations from a set of arrays:
function showCombinations($string, $traits, $i){
if($i >= count($traits)){
echo trim($string) . '<br>';
}else{
foreach($traits[$i] as $trait){
showCombinations("$string$trait", $traits, $i + 1);
}
}
}
$traits = array(
array('1','2'),
array('1','2','3'),
array('1','2','3')
);
showCombinations('', $traits, 0);
However, my problem is that I need to store the results in an array for processing later rather than just print them out but I can't see how this can be done without using a global variable.
Does anyone know of an alternative way to achieve something similar or modify this to give me results I can use?
Return them. Make showCombinations() return a list of items. In the first case you only return one item, in the other recursive case you return a list with all the returned lists merged. For example:
function showCombinations(...) {
$result = array();
if (...) {
$result[] = $item;
}
else {
foreach (...) {
$result = array_merge($result, showCombinations(...));
}
}
return $result;
}
In addition to the other answers, you could pass the address of an array around inside your function, but honestly this isn't nearly the best way to do it.
Using the variable scope modifier static could work. Alternatively, you could employ references, but that's just one more variable to pass. This works with "return syntax".
function showCombinations($string, $traits, $i){
static $finalTraits;
if (!is_array($finalTraits)) {
$finalTraits = array();
}
if($i >= count($traits)){
//echo trim($string) . '<br>';
$finalTraits[] = $string;
} else {
foreach($traits[$i] as $trait){
showCombinations("$string$trait", $traits, $i + 1);
}
}
return $finalTraits;
}
$traits = array(
array('1','2'),
array('1','2','3'),
array('1','2','3')
);
echo join("<br>\n",showCombinations('', $traits, 0));
Of course, this will work as expected exactly once, before the static nature of the variable catches up with you. Therefore, this is probably a better solution:
function showCombinations($string, $traits, $i){
$finalTraits = array();
if($i >= count($traits)){
$finalTraits[] = $string;
} else {
foreach($traits[$i] as $trait){
$finalTraits = array_merge(
$finalTraits,
showCombinations("$string$trait", $traits, $i + 1)
);
}
}
return $finalTraits;
}
although the solution by Lukáš is the purest as it has no side effects, it may be ineffective on large inputs, because it forces the engine to constantly generate new arrays. There are two more ways that seem to be less memory-consuming
have a results array passed by reference and replace the echo call with $result[]=
(preferred) wrap the whole story into a class and use $this->result when appropriate
the class approach is especially nice when used together with php iterators
public function pageslug_genrator($slug,$cat){
$page_check=$this->ci->cms_model->show_page($slug);
if($page_check[0]->page_parents != 0 ){
$page_checks=$this->ci->page_model->page_list($page_check[0]->page_parents);
$cat[]=$page_checks['re_page'][0]->page_slug;
$this->pageslug_genrator($page_checks['re_page'][0]->page_slug,$cat);
}
else
{
return $cat;
}
}
this function doesnt return any value but when i m doing print_r $cat it re
store the results in a $_SESSION variable.