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PHP File Handling with PHP Parsing Specific Formats Reading CSV

Dario Preglej
Dario Preglej
9,771 Points

fgetcsv function

Hello guys!

In this course Alena used : $fh = fopen('data/csv/people.csv', 'r'); $header = fgetcsv($fh); extract(array_flip($header));

and then: while(($contact = fgetcsv($fh)) !== false){}

I don't understand how is that when she used $contact[$first] she got the string "Alena".

var_dump($contact); results: array(5) { [0]=> string(5) "Alena" [1]=> string(8) "Holligan" [2]=> string(14) "sketchings.com" [3]=> string(10) "sketchings" [4]=> string(25) "/img/jV-j2pxp_400x400.jpg" }

var_dump($first); results: int(0)

var_dump($contact[$first]); results: string(5) "Alena"

HOW??

2 Answers

Hey, how's it going.

She used two functions.

1. array_flip() to flip the properties/keys with the values in the array...
ex. 
if
    $temp1 = array(2) { [0]=>"Hey", [1]=>"there" };
then
    array_flip($temp1) = array(2) { ["Hey"]=>0, ["there"]=>1 };

2. extract() to convert the keys/properties of an array into usable variables
    **the VALUES of these variables are the values from the array**...
    ex.
             if 
                $temp2 = array(2) { ["Flavor"]=>"Vanilla",
                                     ["Topping"]=>"Sprinkles" };
             then
                extract($temp2) would return two usable variables(you don't see these get
                returned, that's why it might have been confusing),
                    variable1 is $Flavor
                    variable2 is $Topping
                if you echo these variables you would get
                echo $Flavor;
                echo $Topping;
                -----OUTPUT-------> 
                    Vanilla
                    Sprinkles 

So she used these two functions to create five variables...
             flip_array()                 extract()
[0]=> first   ---------> ["first"]=> 0   ----------> $first = 0
[1]=> last    ---------> ["last"]=> 1    ----------> $last = 1
[2]=> website ---------> ["website"]=> 2 ----------> $website = 2
[3]=> twitter ---------> ["twitter"]=> 3 ----------> $twitter = 3
[4]=> img     ---------> ["img"]=> 4     ----------> $img = 4

...and when using these variables as keys for the $contact array, we get...
$contact[$first] = "Alena"
$contact[$last] = "Holligan"
$contact[$website] = "sketchings.com"
$contact[$twitter] = "http://twitter.com/sketchings"
$contact[$img] = "/img/<img_name>"

She could have just skipped all of these steps and used 0,1,2,3,4 as the keys for the $contact array
$contact[0] = "Alena"
$contact[1] = "Holligan"
$contact[2] = "sketchings.com"
$contact[3] = "http://twitter.com/sketchings"
$contact[4] = "/img/<img_name>"

, but the functions she used here makes the code more readable (it's easier to see what's going on)
Dario Preglej
Dario Preglej
9,771 Points

Yes i undestand that but why echo-ing $contract["first"] she dont get 0? Why she get "Alena"?