How to add elements to an empty array in PHP?

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If I define an array in PHP such as (I don't define its size):

$cart = array();

Do I simply add elements to it using the following?

$cart[] = 13;
$cart[] = "foo";
$cart[] = obj;

Don't arrays in PHP have an add method, for example, cart.add(13)?

Answers

Both array_push and the method you described will work.

$cart = array();
$cart[] = 13;
$cart[] = 14;
// etc

//Above is correct. but below one is for further understanding
$cart = array();
for($i=0;$i<=5;$i++){
    $cart[] = $i;  
}
echo "<pre>";
print_r($cart);
echo "</pre>";

Is the same as:

<?php
$cart = array();
array_push($cart, 13);
array_push($cart, 14);

// Or 
$cart = array();
array_push($cart, 13, 14);
?>

Friday, October 14, 2022

muaddhib-d8370e6581df

Just a try :)

Test 1

With 5 variables

$myvar1 = 'hello';
$myvar2 = 'hello';
$myvar3 = 'hello';
$myvar4 = 'hello';
$myvar4 = 'hello';

print_r(memory_get_usage());

Resut : 618600

Test 2

with 5 array keys

$myvar = array();
$myvar['var1'] = 'hello';
$myvar['var2'] = 'hello';
$myvar['var3'] = 'hello';
$myvar['var4'] = 'hello';
$myvar['var5'] = 'hello';

print_r(memory_get_usage());

Resut : 620256

Tuesday, August 16, 2022

ravi_kilnake

The same way you add to an array when the key is not a concern:

$data[$state]['cities'][] = $city;

Tuesday, November 29, 2022

coolwater

In your foreach loop, call $img->setAttribute('class', 'someclass');. This should do the trick. See more at http://docs.php.net/manual/en/domelement.setattribute.php

Then you need to save the modified document back using $article_header = $doc->saveXml();.

Sunday, October 23, 2022

jonow

I don't think you should consider this from a performance standpoint, rather, look at it from a readability standpoint. The second version collects, well, a collection of things, into a single storage mechanism; from a readability standpoint it's superior.

Not that it matters, but from a performance standpoint I can't imagine the second one costs much, if anything, certainly not enough to overcome the readability benefit.

Friday, August 26, 2022

trigger_eugene

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How to add elements to an empty array in PHP?

Answers

Test 1

Test 2

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