So I have:
$first = "one";
$second = "two";
How can I get values of these variables in:
class TD
{
public $first;
public $second;
}
on the contrary, from here:
class TD
{
public $first = "one";
public $second = "two;
}
to here:
$... = ... ;
$... = ... ;
need to then use it in the query(for ex.):
SELECT * FROM table WHERE cell = $first
Try the following:
$td = new TD;
$first = $td->first;
$second = $td->second;
The above variable $td is an instance of the class TD and it is accessing the classes properties, which are in this case $first and $second. Which is done like this $td->first. Learn all about OOP in PHP.
you can also add a constructor and pass an array for multi params
class TD
{
public $find = [];
public function __construct($arr){
foreach($arr as $k=>$v){
$this->find[$k+1] = $v;
}
}
}
$array = ["one", "two", "tree"];
$td = new TD($array);
var_dump($td->find[1]);
var_dump($td->find[2]);
var_dump($td->find[3]);
Related
In PHP we can do things like these:
Class Example {
...
}
$example = 'Example';
$object = new $example();
Or the use of variable variables:
$hour = 18;
$greets = array('Good morning','Good afternoon','Good evening');
$values = array(13,21,23);//people is sleeping at 23PM, so they don't greet.
$n = count($values);
$greet = 'greets';
for($i=0;$i<$n;$i++){
if($hour < $values[$i]){
echo 'hello, '.${$greet}[$i];
break;
}
}
And others..
I wonder if it would be possible to access directly to a specific index of a multidimensional array in a similar way. Something like:
$array = array(...); //multidimensional array.
$position = '[0][4][3]';
print_r($array$position);
Thanks in advance.
UPDATE
I'm so sorry because I finished my question in a wrong way.
I need to set the multimesional array and add a value. i.e:
$array$position = $data;
You could implement it yourself with a custom function:
function getValueFromMultiDimensionalArray( array $array, string $key )
{
$keys = explode('][', $key);
$value = $array;
foreach ($keys as $theKey) {
// remove the opening or closing bracket if present
$theKey = str_replace([ '[', ']' ], '', $theKey);
if (!isset($value[$theKey])) {
return null;
}
$value = $value[$theKey];
}
return $value;
}
You can define path as dot separated , check the following solution
function getValueByKey($a,$p){
$c = $a;
foreach(explode('.',$p) as $v){
if(!array_key_exists($v, $c)) return null;
$c = $c[$v];
}
return $c;
}
You can use this function as
$path = '1.2.3.0';
$indexValue = getValueByKey($array, $path);
Nope, this is not possible.
The only thing you can do is to implement ArrayAccess interface, which allows to access instances with [] operator. But you will have to define the logic yourself.
class MyClass implements ArrayAccess
{
...
}
$x = new MyClass([0=>[4=>[3=>'hello world']]]);
$position = '[0][4][3]';
echo $x[$position]; //hello world
I have the following scenario:
$class = 'Main\Entity\Redaction'; #or anything else namespaced class
$nameClass = explode('\\', $class);
$jsonNamespace = [];
if (!empty($nameClass[0])) {
$jsonNamespace[$nameClass[0]] = [];
if (!empty($nameClass[1])) {
$jsonNamespace[$nameClass[0]][$nameClass[1]] = [];
if (!empty($nameClass[2])) {
$jsonNamespace[$nameClass[0]][$nameClass[1]][$nameClass[2]] = ['#wherever'];
}
}
}
I want to declare a namespaced object JSON.
Something like this:
{
Main: {
Entity: {
Redaction: ['#wherever']
}
}
}
But without a lot of "IF", something recursive.
You can do this with recursion, but another way is by using a reference. Add a new level to the array, and then simply shift the reference down to that new element.
<?php
function buildArray(array $keys, $value){
$ret = array();
$ref =& $ret;
foreach($keys as $key){
// Add the next level to the array
$ref[$key] = array();
// Then shift the reference, so that the next
// iteration can add a new level
$ref =& $ref[$key];
}
// $ref is a reference to the lowest level added
$ref = array($value);
// Not totally sure if this is needed
unset($ref);
return $ret;
}
$class = 'Main\Entity\Redaction';
$jsonNamespace = buildArray(explode('\\', $class), array('#wherever'));
var_dump($jsonNamespace);
DEMO: http://codepad.org/f7O0Qy3D
I know I can loop through a PHP object and obtain the values of it's members like so:
class MyObject {
public $one = 1;
public $two = 2;
public $three = 3;
function getMemberValues() {
foreach($this as $memb => $value) {
echo $value." ";
}
}
}
$o = new MyObject();
$o->getMemberValues();
// prints 1 2 3
but what I want to be able to do is loop through the members and assign a value to each one.
I can't figure out the syntax for it though.
$this[$memb] = 111;
doesn't work because you get a
Cannot use object of type MyObject as array
error, and
$this->$memb
obviously isn't valid either.
Is this possible?
Many thanks
Yes, $this->$memb is valid.
You can assign to a property like this:
$memb = 'one';
$this->$memb = 1;
This also works for functions, and this is documented here
and
$this->$memb
obviously isn't valid either.
Have you tried it? It looks perfectly valid to me.
foreach ($this as $memb => $val) {
$this->$memb = 'toto';
}
The code above should work perfectly.
Maybe
function getMemberValues() {
foreach($this as &$value) {
$value = $newval;
}
}
http://php.net/manual/en/function.get-object-vars.php
function getMemberValues()
{
echo implode(' ', get_object_vars($this));
}
So I'm trying to learn how to pass arrays through a function, so that I can get around PHP's inability to return multiple values. Haven't been able to get anything to work so far, but here is my best try. Can anybody point out where I'm going wrong?
function foo($array)
{
$array[3]=$array[0]+$array[1]+$array[2];
return $array;
}
$waffles[0]=1;
$waffles[1]=2;
$waffles[2]=3;
foo($waffles);
echo $waffles[3];
For clarification: I want to be able to pass multiple variables into a function, do something, then return multiple variables back out while keeping them seperate. This was just an example I was trying to get working as a work around for not being able to return multiple variables from an array
You seem to be looking for pass-by-reference, to do that make your function look this way (note the ampersand):
function foo(&$array)
{
$array[3]=$array[0]+$array[1]+$array[2];
}
Alternately, you can assign the return value of the function to a variable:
function foo($array)
{
$array[3]=$array[0]+$array[1]+$array[2];
return $array;
}
$waffles = foo($waffles)
You're passing the array into the function by copy. Only objects are passed by reference in PHP, and an array is not an object. Here's what you do (note the &)
function foo(&$arr) { # note the &
$arr[3] = $arr[0]+$arr[1]+$arr[2];
}
$waffles = array(1,2,3);
foo($waffles);
echo $waffles[3]; # prints 6
That aside, I'm not sure why you would do that particular operation like that. Why not just return the sum instead of assigning it to a new array element?
function foo(Array $array)
{
return $array;
}
Try
$waffles = foo($waffles);
Or pass the array by reference, like suggested in the other answers.
In addition, you can add new elements to an array without writing the index, e.g.
$waffles = array(1,2,3); // filling on initialization
or
$waffles = array();
$waffles[] = 1;
$waffles[] = 2;
$waffles[] = 3;
On a sidenote, if you want to sum all values in an array, use array_sum()
I always return multiple values by using a combination of list() and array()s:
function DecideStuffToReturn() {
$IsValid = true;
$AnswerToLife = 42;
// Build the return array.
return array($IsValid, $AnswerToLife);
}
// Part out the return array in to multiple variables.
list($IsValid, $AnswerToLife) = DecideStuffToReturn();
You can name them whatever you like. I chose to keep the function variables and the return variables the same for consistency but you can call them whatever you like.
See list() for more information.
i know a Class is a bit the overkill
class Foo
{
private $sum = NULL;
public function __construct($array)
{
$this->sum[] = $array;
return $this;
}
public function getSum()
{
$sum = $this->sum;
for($i=0;$i<count($sum);$i++)
{
// get the last array index
$res[$i] = $sum[$i] + $sum[count($sum)-$i];
}
return $res;
}
}
$fo = new Foo($myarray)->getSum();
Here is how I do it. This way I can actually get a function to simulate returning multiple values;
function foo($array)
{
foreach($array as $_key => $_value)
{
$str .= "{$_key}=".$_value.'&';
}
return $str = substr($str, 0, -1);
}
/* Set the variables to pass to function, in an Array */
$waffles['variable1'] = "value1";
$waffles['variable2'] = "value2";
$waffles['variable3'] = "value3";
/* Call Function */
parse_str( foo( $waffles ));
/* Function returns multiple variable/value pairs */
echo $variable1 ."<br>";
echo $variable2 ."<br>";
echo $variable3 ."<br>";
Especially usefull if you want, for example all fields in a database
to be returned as variables, named the same as the database table fields.
See 'db_fields( )' function below.
For example, if you have a query
select login, password, email from members_table where id = $id
Function returns multiple variables:
$login, $password and $email
Here is the function:
function db_fields($field, $filter, $filter_by, $table = 'members_table') {
/*
This function will return as variable names, all fields that you request,
and the field values assigned to the variables as variable values.
$filter_by = TABLE FIELD TO FILTER RESULTS BY
$filter = VALUE TO FILTER BY
$table = TABLE TO RUN QUERY AGAINST
Returns single string value or ARRAY, based on whether user requests single
field or multiple fields.
We return all fields as variable names. If multiple rows
are returned, check is_array($return_field); If > 0, it contains multiple rows.
In that case, simply run parse_str($return_value) for each Array Item.
*/
$field = ($field == "*") ? "*,*" : $field;
$fields = explode(",",$field);
$assoc_array = ( count($fields) > 0 ) ? 1 : 0;
if (!$assoc_array) {
$result = mysql_fetch_assoc(mysql_query("select $field from $table where $filter_by = '$filter'"));
return ${$field} = $result[$field];
}
else
{
$query = mysql_query("select $field from $table where $filter_by = '$filter'");
while ($row = mysql_fetch_assoc($query)) {
foreach($row as $_key => $_value) {
$str .= "{$_key}=".$_value.'&';
}
return $str = substr($str, 0, -1);
}
}
}
Below is a sample call to function. So, If we need to get User Data for say $user_id = 12345, from the members table with fields ID, LOGIN, PASSWORD, EMAIL:
$filter = $user_id;
$filter_by = "ID";
$table_name = "members_table"
parse_str(db_fields('LOGIN, PASSWORD, EMAIL', $filter, $filter_by, $table_name));
/* This will return the following variables: */
echo $LOGIN ."<br>";
echo $PASSWORD ."<br>";
echo $EMAIL ."<br>";
We could also call like this:
parse_str(db_fields('*', $filter, $filter_by, $table_name));
The above call would return all fields as variable names.
You are not able to return 'multiple values' in PHP. You can return a single value, which might be an array.
function foo($test1, $test2, $test3)
{
return array($test1, $test2, $test3);
}
$test1 = "1";
$test2 = "2";
$test3 = "3";
$arr = foo($test1, $test2, $test3);
$test1 = $arr[0];
$test2 = $arr[1];
$test3 = $arr[2];
Another way is:
$NAME = "John";
$EMAIL = "John#gmail.com";
$USERNAME = "John123";
$PASSWORD = "1234";
$array = Array ("$NAME","$EMAIL","$USERNAME","$PASSWORD");
function getAndReturn (Array $array){
return $array;
}
print_r(getAndReturn($array));
My goal is to echo the argument passed to a function. For example, how can this be done?
$contact_name = 'foo';
function do_something($some_argument){
// echo 'contact_name' .... How???
}
do_something($contact_name);
You can't. If you want to do that, you need to pass the names as well, e.g:
$contact_name = 'foo';
$contact_phone = '555-1234';
function do_something($args = array()) {
foreach ($args as $name => $value) {
echo "$name: $value<br />";
}
}
do_something(compact('contact_name', 'contact_phone'));
Straight off the PHP.net variables page:
<?php
function vname(&$var, $scope=false, $prefix='unique', $suffix='value')
{
if($scope) $vals = $scope;
else $vals = $GLOBALS;
$old = $var;
$var = $new = $prefix.rand().$suffix;
$vname = FALSE;
foreach($vals as $key => $val) {
if($val === $new) $vname = $key;
}
$var = $old;
return $vname;
}
?>
Not possible.
Variables are just means to address values or areas in the memory. You cannot get the variable name that’s value has been passed to a function.
Disclaimer: this will oonly work if you pass a variable to the function, not a value, and it only works when your not in a function or a class. So only the GLOBAL scope works :)
Good funct($var)
Bad funct(1)
You can do it actually contrary to popular believe ^_^. but it involves a few lookup tricks with the $GLOBALS variable.
you do it like so:
$variable_name = "some value, better if its unique";
function funct($var) {
foreach ($GLOBALS as $name => $value) {
if ($value == $var) {
echo $name; // will echo variable_name
break;
}
}
}
this method is not fool proof tho. Because if two variables have the same value, the function will get the name of the first one it finds. Not the one you want :P
Its best to make the variable value unique before hand if you want accuracy on variable names
Another method would be to use reference to be accurate like so
$variable_name = 123;
function funct(&$var) {
$old = $var;
$var = $checksum = md5(time()); // give it unique value
foreach ($GLOBALS as $name => $value) {
if ($value == $var) {
echo $name; // will echo variable_name
$var = $old; // reassign old value
break;
}
}
}
so it is entirely possible :)
Based on PTBNL's (most definately correct) answer i came up with a more readable (at least i think so) approach:
/**
* returns the name of the variable posted as the first parameter.
* If not called from global scope, pass in get_defined_vars() as the second parameter
*
* behind the scenes:
*
* this function only works because we are passing the first argument by reference.
* 1. we store the old value in a known variable
* 2. we overwrite the argument with a known randomized hash value
* 3. we loop through the scope's symbol table until we find the known value
* 4. we restore the arguments original value and
* 5. we return the name of the symbol we found in the table
*/
function variable_name( & $var, array $scope = null )
{
if ( $scope == null )
{
$scope = $GLOBALS;
}
$__variable_name_original_value = $var;
$__variable_name_temporary_value = md5( number_format( microtime( true ), 10, '', '' ).rand() );
$var = $__variable_name_temporary_value;
foreach( $scope as $variable => $value )
{
if ( $value == $__variable_name_temporary_value && $variable != '__variable_name_original_value' )
{
$var = $__variable_name_original_value;
return $variable;
}
}
return null;
}
// prove that it works:
$test = 1;
$hello = 1;
$world = 2;
$foo = 100;
$bar = 10;
$awesome = 1;
function test_from_local_scope()
{
$local_test = 1;
$local_hello = 1;
$local_world = 2;
$local_foo = 100;
$local_bar = 10;
$local_awesome = 1;
return variable_name( $local_awesome, get_defined_vars() );
}
printf( "%s\n", variable_name( $awesome, get_defined_vars() ) ); // will echo 'awesome'
printf( "%s\n", test_from_local_scope() ); // will also echo awesome;
Sander has the right answer, but here is the exact thing I was looking for:
$contact_name = 'foo';
function do_something($args = array(), $another_arg) {
foreach ($args as $name => $value) {
echo $name;
echo '<br>'.$another_arg;
}
}
do_something(compact(contact_name),'bar');
class Someone{
protected $name='';
public function __construct($name){
$this->name=$name;
}
public function doSomthing($arg){
echo "My name is: {$this->name} and I do {$arg}";
}
}
//in main
$Me=new Someone('Itay Moav');
$Me->doSomething('test');