Question

How can i set the function as a variable in php Similar to list function

example: list($x,$y)=array(1,2); // this is okey ,but...

How do I create such a structure?

Answer 1

You are talking about variable function that if a variable name has parentheses appended to it, PHP will look for a function with the same name as whatever the variable evaluates to, and will attempt to execute it. Among other things, this can be used to implement callbacks, function tables, and so forth.

Here is the little example from PHP manual Variable Functions

function foo() {
    echo "In foo()<br />\n";
}

function bar($arg = '')
{
    echo "In bar(); argument was '$arg'.<br />\n";
}

// This is a wrapper function around echo
function echoit($string)
{
    echo $string;
}

$func = 'foo';
$func();        // This calls foo()

$func = 'bar';
$func('test');  // This calls bar()

$func = 'echoit';
$func('test');  // This calls echoit()

and the other scenario is Anonymous functions, also known as closures, allow the creation of functions which have no specified name. They are most useful as the value of callback parameters, but they have many other uses.

$greet = function($name)
{
    printf("Hello %s\r\n", $name);
};

$greet('World');
$greet('PHP');

Answer 2

<?php
$my_array = array("Dog","Cat","Horse");

list($a, $b, $c) = $my_array;
echo "I have several animals, a $a, a $b and a $c.";
?>

The list() function is used to assign values to a list of variables. Like array(), this is not really a function, but a language construct. list() is used to assign a list of variables in one operation.

Initialize the function In the form of Variable in php

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